The document describes a functional model of a conditional access system developed by EBU Project Group B/CA. The model provides a framework for defining the terms and operating principles of conditional access systems used for encrypted digital television broadcasts. It is intended to help members evaluate different conditional access system options available and understand the trade-offs involved in their design, rather than specifying a particular system. The model illustrates key components like scrambling, encryption of electronic keys, and subscriber management systems.
OCR Presentation (Optical Character Recognition)Neeraj Neupane
Optical Character Recognition (OCR) is a technology that converts non-digital text into editable formats. It works by recognizing printed or written characters using computer vision techniques. The document describes the architecture and objectives of an OCR system, including converting documents to text, speeding up processing, and embedding in applications. It outlines common OCR methods such as grayscaling, binarization, noise removal, sharpening, segmentation, feature extraction, and recognition to identify characters. Diagrams show the system architecture and workflow. Screenshots demonstrate the developed OCR system in use. The conclusion discusses automatic data entry and future areas like recognizing handwriting.
OCR (Optical Character Recognition) is a technology that recognizes text within digital images. It examines text in documents and converts characters into machine-readable code. OCR is commonly used to convert printed paper documents into editable digital text files. The basic process involves preprocessing the image to clean it up, isolating individual characters, and using character recognition libraries or more advanced techniques to identify each character and assign it the corresponding text. OCR is needed to convert scanned documents into text-searchable files that can be edited, searched, and managed more easily within document systems.
Optical character recognition (ocr) pptDeijee Kalita
The document discusses optical character recognition (OCR), which is the process of converting scanned images of printed or handwritten text into machine-encoded text. It provides a brief history of OCR, explaining some of the early developments. It also outlines the typical steps involved, including pre-processing, character recognition, and post-processing. Examples of applications of OCR technology are given.
This document discusses instruction-level parallelism (ILP), which refers to executing multiple instructions simultaneously in a program. It describes different types of parallel instructions that do not depend on each other, such as at the bit, instruction, loop, and thread levels. The document provides an example to illustrate ILP and explains that compilers and processors aim to maximize ILP. It outlines several ILP techniques used in microarchitecture, including instruction pipelining, superscalar, out-of-order execution, register renaming, speculative execution, and branch prediction. Pipelining and superscalar processing are explained in more detail.
Real-time operating systems are designed to handle tasks with strict timing constraints. They manage computer hardware resources and provide services to real-time computer programs. Real-time tasks must be completed by their deadlines to maintain the correct functionality of systems like digital controls that periodically sense status and actuate systems. Real-time operating systems prioritize predictability and ensuring tasks meet timing deadlines over average performance metrics. They schedule processors and allocate memory in a way that guarantees tasks will finish processing by their required times.
This document discusses Human Computer Interfaces (HCI). It defines HCI as the interaction between humans and computers. It describes different types of interfaces like command line, menu driven, and graphical user interfaces. It also discusses existing technologies in HCI like physical devices that rely on vision, audio, and touch. The document outlines advances in areas like wearable devices, wireless technologies, and virtual realities. It describes architectures like uni-modal and multi-modal systems. Applications discussed include intelligent homes and helping disabled people.
The document discusses the key components and structure of operating systems. It covers:
1) The main components of an OS include process management, memory management, I/O management, secondary storage management, file management, protection systems, accounting systems, and more.
2) Traditionally, OSes were structured as monolithic kernels containing all components, but this poses reliability and maintenance issues. Alternative structures include layering and microkernels.
3) Layering implements an OS as a set of layers, where each layer provides an abstract "machine" to the layer above. This improves modularity but can hurt performance.
4) Microkernels minimize kernel code and implement OS services as user-level processes for
Cache memory is a small, fast memory located close to the processor that stores frequently accessed instructions and data. There are typically three levels of cache (L1, L2, L3) with L1 being the smallest and fastest cache located directly on the CPU chip. The performance of a cache is measured by its hit ratio, with a higher hit ratio indicating better performance as the CPU is less likely to access the slower main memory.
OCR Presentation (Optical Character Recognition)Neeraj Neupane
Optical Character Recognition (OCR) is a technology that converts non-digital text into editable formats. It works by recognizing printed or written characters using computer vision techniques. The document describes the architecture and objectives of an OCR system, including converting documents to text, speeding up processing, and embedding in applications. It outlines common OCR methods such as grayscaling, binarization, noise removal, sharpening, segmentation, feature extraction, and recognition to identify characters. Diagrams show the system architecture and workflow. Screenshots demonstrate the developed OCR system in use. The conclusion discusses automatic data entry and future areas like recognizing handwriting.
OCR (Optical Character Recognition) is a technology that recognizes text within digital images. It examines text in documents and converts characters into machine-readable code. OCR is commonly used to convert printed paper documents into editable digital text files. The basic process involves preprocessing the image to clean it up, isolating individual characters, and using character recognition libraries or more advanced techniques to identify each character and assign it the corresponding text. OCR is needed to convert scanned documents into text-searchable files that can be edited, searched, and managed more easily within document systems.
Optical character recognition (ocr) pptDeijee Kalita
The document discusses optical character recognition (OCR), which is the process of converting scanned images of printed or handwritten text into machine-encoded text. It provides a brief history of OCR, explaining some of the early developments. It also outlines the typical steps involved, including pre-processing, character recognition, and post-processing. Examples of applications of OCR technology are given.
This document discusses instruction-level parallelism (ILP), which refers to executing multiple instructions simultaneously in a program. It describes different types of parallel instructions that do not depend on each other, such as at the bit, instruction, loop, and thread levels. The document provides an example to illustrate ILP and explains that compilers and processors aim to maximize ILP. It outlines several ILP techniques used in microarchitecture, including instruction pipelining, superscalar, out-of-order execution, register renaming, speculative execution, and branch prediction. Pipelining and superscalar processing are explained in more detail.
Real-time operating systems are designed to handle tasks with strict timing constraints. They manage computer hardware resources and provide services to real-time computer programs. Real-time tasks must be completed by their deadlines to maintain the correct functionality of systems like digital controls that periodically sense status and actuate systems. Real-time operating systems prioritize predictability and ensuring tasks meet timing deadlines over average performance metrics. They schedule processors and allocate memory in a way that guarantees tasks will finish processing by their required times.
This document discusses Human Computer Interfaces (HCI). It defines HCI as the interaction between humans and computers. It describes different types of interfaces like command line, menu driven, and graphical user interfaces. It also discusses existing technologies in HCI like physical devices that rely on vision, audio, and touch. The document outlines advances in areas like wearable devices, wireless technologies, and virtual realities. It describes architectures like uni-modal and multi-modal systems. Applications discussed include intelligent homes and helping disabled people.
The document discusses the key components and structure of operating systems. It covers:
1) The main components of an OS include process management, memory management, I/O management, secondary storage management, file management, protection systems, accounting systems, and more.
2) Traditionally, OSes were structured as monolithic kernels containing all components, but this poses reliability and maintenance issues. Alternative structures include layering and microkernels.
3) Layering implements an OS as a set of layers, where each layer provides an abstract "machine" to the layer above. This improves modularity but can hurt performance.
4) Microkernels minimize kernel code and implement OS services as user-level processes for
Cache memory is a small, fast memory located close to the processor that stores frequently accessed instructions and data. There are typically three levels of cache (L1, L2, L3) with L1 being the smallest and fastest cache located directly on the CPU chip. The performance of a cache is measured by its hit ratio, with a higher hit ratio indicating better performance as the CPU is less likely to access the slower main memory.
Reduced instruction set computing, or RISC (pronounced 'risk', /ɹɪsk/), is a CPU design strategy based on the insight that a simplified instruction set provides higher performance when combined with a microprocessor architecture capable of executing those instructions using fewer microprocessor cycles per instruction.
Optical character recognition (OCR) is the conversion of images of typed or printed text into machine-encoded text. The document discusses OCR including defining it, describing its problem overview, types, steps in the OCR process like pre-processing and character recognition, accuracy considerations, use of free OCR software, pros and cons, and areas for further research like improving recognition of cursive text.
Interrupts allow input/output devices to alert the processor when they are ready. When an interrupt request occurs, the processor saves its context and jumps to an interrupt service routine. It then acknowledges the interrupt and restores its context before returning to the original instruction. Processors have mechanisms for prioritizing interrupts and enabling/disabling them to avoid infinite loops or unintended requests.
DSM system
Shared memory
On chip memory
Bus based multiprocessor
Working through cache
Write through cache
Write once protocol
Ring based multiprocessor
Protocol used
Similarities and differences b\w ring based and bus based
Designing for performance.
Performance balance.
single processor and Multi core processor.
Usage of Processors.
Usage of single processor and Multi core Processor.
Processing Techniques.
Moors law
This document discusses processes and threads in Perl programming. It defines a process as an instance of a running program, while a thread is a flow of control through a program with a single execution point. Multiple threads can run within a single process and share resources, while processes run independently. The document compares processes and threads, and covers creating and managing threads, sharing data between threads, synchronization, and inter-process communication techniques in Perl like fork, pipe, and open.
This document provides an overview of an emotion based music player project. It discusses recognizing a user's facial emotions using machine learning and playing songs to match their detected mood. The proposed system aims to automatically play appropriate music without needing manual playlist selection. It outlines the existing manual music selection process, proposes an emotion recognition and song matching solution, and details the software requirements and design models to be used, including ER diagrams, class diagrams, use cases and sequences. The document concludes by discussing project modules and the future scope of the emotion based music player.
File system and IOCS
Files and file organization
Fundamentals of file organizations
Directory structures
File protection
Interface between file system and IOCS
Allocation of disk space
Implementation of file access
The document discusses video compression techniques. It describes video compression as removing repetitive images, sounds, and scenes to reduce file size. There are two types: lossy compression which removes unnecessary data, and lossless compression which compresses without data loss. Common techniques involve predicting frames, exploiting temporal and spatial redundancies, and standards like MPEG. Applications include cable TV, video conferencing, storage media. Advantages are reduced file sizes and faster transfer, while disadvantages are recompilation needs and potential transmission errors.
Currency recognition system using image processingFatima Akhtar
This document outlines a currency recognition system based on image processing. The system aims to help people recognize different currencies from around the world more easily. It extracts features from images of currency, such as identification marks and latent images, and uses template matching to compare these to stored images of genuine currency notes. The system is intended to be implemented as a web application so that people can use it anywhere at any time to identify currencies and check if they are genuine or counterfeit.
An interactive debugging system provides programmers tools to test and debug programs. It allows tracing program execution and viewing variable values. A good debugging system displays the program and tracks changes. It works closely with other system components and has a simple user interface using menus and screens.
This document discusses multimedia data compression. It explains that multimedia files like images, audio, and video take up significantly more storage space than text files. Data compression reduces the size of files by removing redundant data, saving storage space and allowing faster transfers. Compression is achieved through codecs, which are hardware or software that compresses and decompresses data. Compression can be lossless, allowing exact reconstruction of the original data, or lossy, which sacrifices some quality to achieve greater compression but does not allow exact reconstruction.
I/O ports allow connection between computers and peripheral devices like keyboards, mice and monitors. There are two main types of ports: serial ports which transmit data one bit at a time, and parallel ports which allow simultaneous transmission of multiple bits of data. Common ports include VGA, DVI, HDMI and USB. Device drivers act as an interface between the operating system and device controllers to allow communication between I/O devices and the CPU. There are three main I/O mechanisms: programmed I/O where the CPU directly controls I/O, interrupts where devices signal the CPU when ready, and DMA which allows hardware subsystems to access memory independently of the CPU.
Speech recognition, also known as automatic speech recognition, allows a computer to understand human voice and perform tasks. It uses acoustic and language models to recognize speech. Acoustic models are statistical representations of sounds created from audio recordings and transcriptions, while language models predict word sequences. There are two main types: speaker-dependent systems require user training to recognize individual voices more accurately, while speaker-independent systems used in applications like phones do not require training but are generally less accurate. The speech recognition process involves digitizing speech, analyzing acoustic signals, and linguistically interpreting the speech to recognize words.
This document discusses real-time operating system (RTOS) concepts. It defines real-time as responsiveness defined by external processes. An RTOS guarantees tasks will finish within time constraints. It explains characteristics like preemptive multitasking, prioritized processes, interrupt handling. The document also covers RTOS scheduling, dispatching, time specifications for tasks and interrupts. Common real-time applications are also listed like military, telecommunications, aviation and more.
This document summarizes an OCR system for recognizing handwritten text and signatures. It discusses optical character recognition (OCR) and its benefits. The proposed technique uses Freeman's Chain Code for feature extraction and Euclidean distance for image recognition. Key steps include pre-processing, feature extraction using center of mass, longest radius, track steps and sectors, and relationships between pixels, classification, and post-processing for accuracy. Testing achieved over 70% accuracy on the character "A".
The document discusses audio compression techniques. It begins with an introduction to pulse code modulation (PCM) and then describes μ-law and A-law compression standards which compress audio using companding algorithms. It also covers differential PCM and adaptive differential PCM (ADPCM) techniques. The document then discusses the MPEG audio compression standard, including its encoder architecture, three layer standards (Layers I, II, III), and applications. It concludes with a comparison of various MPEG audio compression standards and references.
The document discusses the practical issues involved in implementing a digital television headend using the DVB Simulcrypt standard. It examines the roles and interfaces of the different components as defined in the standard, such as the Entitlement Information System (EIS) and Simulcrypt Synchronizer (SCS). It finds that some important interfaces are not currently defined, such as between the EIS and multiplexer configurer, which can cause synchronization problems. It evaluates different practical architectures for implementing the system and discusses issues to consider, such as system synchronization and timing.
Reduced instruction set computing, or RISC (pronounced 'risk', /ɹɪsk/), is a CPU design strategy based on the insight that a simplified instruction set provides higher performance when combined with a microprocessor architecture capable of executing those instructions using fewer microprocessor cycles per instruction.
Optical character recognition (OCR) is the conversion of images of typed or printed text into machine-encoded text. The document discusses OCR including defining it, describing its problem overview, types, steps in the OCR process like pre-processing and character recognition, accuracy considerations, use of free OCR software, pros and cons, and areas for further research like improving recognition of cursive text.
Interrupts allow input/output devices to alert the processor when they are ready. When an interrupt request occurs, the processor saves its context and jumps to an interrupt service routine. It then acknowledges the interrupt and restores its context before returning to the original instruction. Processors have mechanisms for prioritizing interrupts and enabling/disabling them to avoid infinite loops or unintended requests.
DSM system
Shared memory
On chip memory
Bus based multiprocessor
Working through cache
Write through cache
Write once protocol
Ring based multiprocessor
Protocol used
Similarities and differences b\w ring based and bus based
Designing for performance.
Performance balance.
single processor and Multi core processor.
Usage of Processors.
Usage of single processor and Multi core Processor.
Processing Techniques.
Moors law
This document discusses processes and threads in Perl programming. It defines a process as an instance of a running program, while a thread is a flow of control through a program with a single execution point. Multiple threads can run within a single process and share resources, while processes run independently. The document compares processes and threads, and covers creating and managing threads, sharing data between threads, synchronization, and inter-process communication techniques in Perl like fork, pipe, and open.
This document provides an overview of an emotion based music player project. It discusses recognizing a user's facial emotions using machine learning and playing songs to match their detected mood. The proposed system aims to automatically play appropriate music without needing manual playlist selection. It outlines the existing manual music selection process, proposes an emotion recognition and song matching solution, and details the software requirements and design models to be used, including ER diagrams, class diagrams, use cases and sequences. The document concludes by discussing project modules and the future scope of the emotion based music player.
File system and IOCS
Files and file organization
Fundamentals of file organizations
Directory structures
File protection
Interface between file system and IOCS
Allocation of disk space
Implementation of file access
The document discusses video compression techniques. It describes video compression as removing repetitive images, sounds, and scenes to reduce file size. There are two types: lossy compression which removes unnecessary data, and lossless compression which compresses without data loss. Common techniques involve predicting frames, exploiting temporal and spatial redundancies, and standards like MPEG. Applications include cable TV, video conferencing, storage media. Advantages are reduced file sizes and faster transfer, while disadvantages are recompilation needs and potential transmission errors.
Currency recognition system using image processingFatima Akhtar
This document outlines a currency recognition system based on image processing. The system aims to help people recognize different currencies from around the world more easily. It extracts features from images of currency, such as identification marks and latent images, and uses template matching to compare these to stored images of genuine currency notes. The system is intended to be implemented as a web application so that people can use it anywhere at any time to identify currencies and check if they are genuine or counterfeit.
An interactive debugging system provides programmers tools to test and debug programs. It allows tracing program execution and viewing variable values. A good debugging system displays the program and tracks changes. It works closely with other system components and has a simple user interface using menus and screens.
This document discusses multimedia data compression. It explains that multimedia files like images, audio, and video take up significantly more storage space than text files. Data compression reduces the size of files by removing redundant data, saving storage space and allowing faster transfers. Compression is achieved through codecs, which are hardware or software that compresses and decompresses data. Compression can be lossless, allowing exact reconstruction of the original data, or lossy, which sacrifices some quality to achieve greater compression but does not allow exact reconstruction.
I/O ports allow connection between computers and peripheral devices like keyboards, mice and monitors. There are two main types of ports: serial ports which transmit data one bit at a time, and parallel ports which allow simultaneous transmission of multiple bits of data. Common ports include VGA, DVI, HDMI and USB. Device drivers act as an interface between the operating system and device controllers to allow communication between I/O devices and the CPU. There are three main I/O mechanisms: programmed I/O where the CPU directly controls I/O, interrupts where devices signal the CPU when ready, and DMA which allows hardware subsystems to access memory independently of the CPU.
Speech recognition, also known as automatic speech recognition, allows a computer to understand human voice and perform tasks. It uses acoustic and language models to recognize speech. Acoustic models are statistical representations of sounds created from audio recordings and transcriptions, while language models predict word sequences. There are two main types: speaker-dependent systems require user training to recognize individual voices more accurately, while speaker-independent systems used in applications like phones do not require training but are generally less accurate. The speech recognition process involves digitizing speech, analyzing acoustic signals, and linguistically interpreting the speech to recognize words.
This document discusses real-time operating system (RTOS) concepts. It defines real-time as responsiveness defined by external processes. An RTOS guarantees tasks will finish within time constraints. It explains characteristics like preemptive multitasking, prioritized processes, interrupt handling. The document also covers RTOS scheduling, dispatching, time specifications for tasks and interrupts. Common real-time applications are also listed like military, telecommunications, aviation and more.
This document summarizes an OCR system for recognizing handwritten text and signatures. It discusses optical character recognition (OCR) and its benefits. The proposed technique uses Freeman's Chain Code for feature extraction and Euclidean distance for image recognition. Key steps include pre-processing, feature extraction using center of mass, longest radius, track steps and sectors, and relationships between pixels, classification, and post-processing for accuracy. Testing achieved over 70% accuracy on the character "A".
The document discusses audio compression techniques. It begins with an introduction to pulse code modulation (PCM) and then describes μ-law and A-law compression standards which compress audio using companding algorithms. It also covers differential PCM and adaptive differential PCM (ADPCM) techniques. The document then discusses the MPEG audio compression standard, including its encoder architecture, three layer standards (Layers I, II, III), and applications. It concludes with a comparison of various MPEG audio compression standards and references.
The document discusses the practical issues involved in implementing a digital television headend using the DVB Simulcrypt standard. It examines the roles and interfaces of the different components as defined in the standard, such as the Entitlement Information System (EIS) and Simulcrypt Synchronizer (SCS). It finds that some important interfaces are not currently defined, such as between the EIS and multiplexer configurer, which can cause synchronization problems. It evaluates different practical architectures for implementing the system and discusses issues to consider, such as system synchronization and timing.
The document provides implementation guidelines for using the DVB Simulcrypt standard, including describing the architecture and protocols, clarifying differences between protocol versions, explaining state diagrams and processes, and providing recommendations for error handling, redundancy management, and custom signaling. It aims to facilitate reliable implementation of the Simulcrypt model and interfaces between broadcasters, network operators, and manufacturers.
The document discusses security vulnerabilities in digital video broadcast chipsets used for digital satellite TV. It begins with background on digital satellite TV security, including how premium content is encrypted and control words are used for decryption. It then describes challenges with analyzing the security of proprietary broadcast chipsets, which implement encryption pairing functions in hardware. The document outlines researchers' approach to gathering information through documentation and reverse engineering to analyze chipset security implementations and identify weaknesses.
The document provides a functional model of a conditional access system for digital television broadcasts. It describes:
- The basic process of scrambling and descrambling broadcast signals.
- How entitlement control messages are used to encrypt control words and allow authorized decoders to descramble content.
- How entitlement management messages are sent by the subscriber authorization system to activate or deactivate decoders.
The model is intended to help members evaluate different conditional access systems, not as a specification for a specific system. It illustrates key aspects like scrambling, control words, and subscriber authorization without promoting any single technical solution.
This document provides training information for teachers and administrators on new features in Moodle 2, including customizing the home page, expanding the workspace, improved navigation, conditional access to resources, advanced grading forms, sharing quiz questions, mobile compatibility, using cohorts to create groups, and configuring file repositories to access files outside of Moodle. Videos and additional resources are provided to demonstrate how to use these new features.
This document describes the head-end architecture and synchronization for digital video broadcasting using SimulCrypt. It defines components such as the event information scheduler, SimulCrypt synchronizer, entitlement control message generator, and multiplexer. Interfaces between these components are also described, including processes for establishing and closing channels and streams, as well as bandwidth allocation and handling errors.
The document provides an overview of digital TV standards, technologies, and requirements. It discusses the different standard organizations for terrestrial, cable, and satellite broadcasting and their associated standards. It also summarizes the key digital TV concepts of networks, throughput, video presentations, receiver architecture, compression technologies, and content protection methods like conditional access and digital rights management.
presentation on NANO-TECH REGENERATIVE FUEL CELLcutejuhi
This document describes a nano-tech regenerative fuel cell that uses carbon nanotubes for onboard hydrogen storage. Hydrogen is fed into a fuel cell where it reacts with oxygen to produce electricity and water. The water is then electrolyzed to regenerate hydrogen, making this a renewable system. Integrating nanotechnology allows for easier hydrogen storage and higher fuel cell efficiency compared to internal combustion engines. This nano-tech regenerative fuel cell provides a pollution-free way to power vehicles.
This document summarizes a seminar on infrared plastic solar cells. It discusses how plastic solar cells use nanotechnology to harness infrared radiation from the sun through semiconductor nanorods, allowing them to generate electricity even on cloudy days. This overcomes limitations of conventional solar panels. While plastic cells are more efficient, a current limitation is their higher cost compared to traditional panels. The seminar covers solar energy basics, nanotechnology applications, infrared radiation properties, types of solar cells, and advantages of plastic cells for harnessing more of the sun's energy spectrum.
Nano Tech Fuels presents eeFuel, a fuel enhancer that improves fuel efficiency and reduces emissions using nanotechnology. It has over 25 years of experience and products used in 15 billion miles of driving with no damage reported. eeFuel supercharges performance in petrol, diesel, bio-diesel, ethanol and heavy fuel oil. It provides benefits like improved fuel economy, lower emissions, and extended engine life while being safe, earth-friendly and suitable for most engines.
This document summarizes a seminar presentation on ultrasonic motors. It describes how ultrasonic motors work using the piezoelectric effect to convert electric energy to motion. Ultrasonic motors offer advantages over electromagnetic motors like high torque, accuracy, and lack of magnetic interference. They can be used in applications requiring small precise motions like cameras, watches, robots, and hardware positioning. While ultrasonic motors have advantages, further research is needed to reduce friction and piezoelectric material costs to improve their usefulness.
The document discusses how nanotechnology can improve fuel cell efficiency in several ways. It explains that nanoparticles increase the surface area of electrodes, making reactions more efficient. Carbon nanotubes are used to store hydrogen by taking advantage of their small diameter. Researchers are also developing non-platinum catalysts made from graphene coated in cobalt nanoparticles and platinum-cobalt composites to increase catalytic activity. Nanoparticle electrolytes also dramatically increase active surface area. These nanotechnology approaches aim to address limitations that have prevented widespread commercial use of fuel cells.
This document provides an overview of ultrasonic motors. It begins with introducing the principle of piezoelectricity that ultrasonic motors are based on. It then describes the typical construction of an ultrasonic motor including the actuator, stator, rotor and casing. The working principle involves generating ultrasonic surface waves on the stator using the actuator that causes friction with the rotor, rotating it. It classifies ultrasonic motors and discusses their advantages like high torque and efficiency, and disadvantages like requiring high frequency power. It concludes by describing some applications like in cameras and automobiles.
This document discusses ultrasonic motors. It begins with an introduction describing how ultrasonic motors were developed and their advantages over traditional motors at small scales. It then covers key topics such as piezoelectricity, poling, basic principles of operation, construction, types including standing wave and traveling wave motors, driver circuits, control techniques, applications, and advantages/disadvantages. In summary, the document provides an overview of ultrasonic motors, how they work using piezoelectric effects, their construction and operating principles, examples of different types, and their applications and benefits.
Ultrasonic motors use piezoelectric materials to generate ultrasonic vibrations that produce motion. They were first introduced in 1965 and have advantages over traditional electromagnetic motors like higher torque at lower speeds, greater precision, and no magnetic interference. Common piezoelectric materials used include quartz, barium titanate, and lead zirconate titanate. Ultrasonic motors find applications in areas like cameras, watches, printers, and medical devices due to their small size and precision.
The document discusses ultrasonic piezoelectric motors. It explains that piezoelectric motors use the piezoelectric effect to convert electrical energy to mechanical vibrations, generating a traveling surface wave that causes friction to drive a rotor. The motor has a piezoelectric actuator, stator, and rotor in a protective casing. It operates more efficiently than electromagnetic motors, with advantages like high torque, accuracy, and no electromagnetic interference. However, piezoelectric materials and high frequency power supplies can increase costs. Applications include cameras, watches, vehicles, robots, and medical devices.
Nanotechnology is the nexus of sciences.
It includes anything smaller than 100 nanometers with novel properties.
The conventional solar cells that are used to harness solar energy are less efficient and cannot function properly on a cloudy day.
The use of nanotechnology in the solar cells created an opportunity to overcome this problem , thereby increasing the efficiency.
The following photos were entirely taken and processed by me with an iPhone. See more: http://paulgordonbrown.com/category/iphoneography/
iPhoneography is the art of creating photos with an Apple iPhone. This is a style of mobile photography that differs from all other forms of digital photography in that images are both shot and processed on the iOS device.
Systems and Network Analysis Center Information Assurance ...Videoguy
Video teleconferencing (VTC) allows users in different locations to interact face-to-face by transmitting audio, video, and data streams. There are dedicated and desktop VTC systems, with dedicated systems containing all necessary components. Standard protocols like SIP, H.320, and H.323 are used. Point-to-point VTC connects two endpoints directly, while multi-party VTC uses a Multipoint Conference Unit (MCU) as a bridge. Gateways connect VTC to other networks like PSTN. Default settings leave VTC vulnerable to unauthorized access and exploitation. Mitigation actions include changing passwords, enabling encryption, disabling features, and updating firmware.
The document proposes protocols for secure launch of virtual machines (VMs) in Infrastructure as a Service (IaaS) clouds. This would provide cloud tenants assurance that their VM instances were launched on hosts with expected software stacks. Currently, cloud tenants have limited control over security mechanisms and lack symbols confirming the integrity of their VM hosts. The proposed protocols aim to address this by verifying platform integrity for hosts and giving tenants symbols of expected code stacks for their launched VMs.
Bandit framework for systematic learning in wireless video based face recogni...ieeepondy
This document proposes a bandit-based learning framework to optimize video-based face recognition over wireless networks and cloud computing. It introduces two multi-armed bandit algorithms that use contextual information to adapt transmission parameters and maximize recognition rates. The algorithms are shown to outperform reinforcement learning methods, reducing video frames processed by 17-44% and network traffic by 12-37%.
This document summarizes a research paper on outsourced attribute-based signatures (OABS). It discusses how existing attribute-based signature (ABS) schemes have high computational costs for signing that scale with the complexity of the predicate formula. To address this, the paper proposes two new OABS schemes that reduce the computation required for signing by outsourcing parts of the signing process to an untrusted cloud server. The first scheme reduces the number of exponentiations in signing from O(d) to O(1), while the second builds on an existing construction and reduces exponentiations from O(d^2) to O(d). Security analysis shows the schemes achieve unforgeability and privacy.
To Get any Project for CSE, IT ECE, EEE Contact Me @ 09666155510, 09849539085 or mail us - ieeefinalsemprojects@gmail.com-Visit Our Website: www.finalyearprojects.org
This document describes a proposed system for outsourced attribute-based signatures (OABS). Existing ABS schemes require heavy computation during signing that grows with the complexity of the predicate formula. The proposed OABS system reduces this computational overhead by outsourcing intensive computations to an untrusted signing cloud service provider. It presents two OABS schemes - the first reduces exponentiations from O(d) to O(1), the second builds on an existing construction and reduces exponentiations from O(d2) to O(d). Security analysis shows the schemes provide unforgeability and privacy. The system allows for high efficiency and flexibility while also achieving accountability.
To Get any Project for CSE, IT ECE, EEE Contact Me @ 09666155510, 09849539085 or mail us - ieeefinalsemprojects@gmail.com-Visit Our Website: www.finalyearprojects.org
A Scalable Network Monitoring and Bandwidth Throttling System for Cloud Compu...Nico Huysamen
This document summarizes a scalable network monitoring and bandwidth throttling system for cloud computing. The system monitors network usage of users on a cloud to identify those abusing bandwidth. It uses a client-server model where virtual machines run client software to monitor their own traffic and report to servers monitoring each cluster. When bandwidth thresholds are exceeded, servers calculate new bandwidth limits for abusive users to normalize network usage across the cloud. The system was tested on Amazon EC2 using over a million simulated clients to evaluate its scalability.
This document contains definitions of common networking terms starting with letters A through D. Some of the key terms defined include: access method, acknowledgement, address resolution protocol (ARP), adjacency table, American Standard Code for Information Interchange (ASCII), bandwidth, best-effort delivery, Bootstrap Protocol (BOOTP), Bring Your Own Device (BYOD), broadcast, burned-in-address (BIA), Carrier Sense Multiple Access (CSMA), channel, circuit switched, Cisco Express Forwarding (CEF), classful addressing, classless addressing, client, client-server, cloud computing, coaxial cable, collaboration, connectionless, connection-oriented, content addressable memory (CAM) table, converged network, crosst
This document provides definitions for many common networking terms. It includes definitions for networking concepts like access methods, addresses (MAC, IP, etc.), protocols (ARP, DHCP, DNS), network devices (routers, switches, firewalls), transmission media (coaxial cable, fiber), and more. The glossary provides concise explanations of important networking components and how they relate to each other at different layers of the OSI model.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
An ethernet based_approach_for_tm_data_analysis_v2Priyasloka Arya
Testing and performance evaluation of flight vehicles largely depends on the data gathered through telemetry. Tele-metered data describes the internal story of device under test. As the tele-metered data is transmitted to ground receiving stations through radio frequency and Inter Range Instrumentation Group (IRIG) standard data format are well known, anybody who is tuned to transmitted frequency, can receive data and minimal information about the format can reveal the total information of device under test. To deal with this situation, current trend is to encrypt the mission critical information on board before transmitting. In this paper, the authors have discussed the advantage of Local Area Network (LAN) based Telemetry base band system which provides scalability, modularity, and flexibility to the user for the analysis of encrypted data.
This document outlines the scope for a CCTV central monitoring system software application. The key aspects are:
1) The software will allow observers to monitor live and recorded video from 54 store locations from a central location and send alerts to store managers about any incidents.
2) It will integrate workflows for setting up reporting items, assigning observers to locations, and alerts for incidents.
3) The software will convert analog camera feeds to digital format and allow simultaneous viewing, playback, recording and archiving of video across the network. It will also include user authorization controls and settings for video quality.
SCADA.pptx supervisory control and data aquasitionRapidAcademy
The document discusses the history and components of SCADA (Supervisory Control and Data Acquisition) systems. It describes how early SCADA systems involved direct connections between sensors and control panels, while modern systems involve remote terminal units, programmable logic controllers, telemetry, and computer software. The key components of a SCADA system include remote terminal units that interface with field sensors, communication systems to transfer data, master stations to display and control the system, and software for user interfaces, alarms, data storage and more.
44Con 2014: GreedyBTS - Hacking Adventures in GSMiphonepentest
This presentation examines insecurities in the 2.5G GSM protocol and demonstrates GreedyBTS; a platform for fingerprinting and exploiting cellular devices, including interception of SMS and voice data.
Cybercom Enhanced Security Platform, CESP, is an integrated platform
that provides comprehensive security functions for high assurance
applications that require high level of security and protection.
CESP has been developed based on the latest technology to be able
to create a robust and flexible solution that conforms to the highest
standard of performance and security.
This document proposes a robust remote authentication mechanism using biometrics and video steganography. It involves encrypting biometric data like facial images and hiding it in video frames during transmission over wireless networks. Existing methods are prone to Trojan horse and other attacks during remote examinations or interviews. The proposed method uses qualified significant wavelet trees to select coefficients in the video frames to embed the encrypted biometric signal, providing security against attacks while allowing for remote authentication. It has applications in content identification, protection and filtering for media like movies. The technique addresses both spatial and temporal domains for robust authentication.
This document discusses establishing an online surveillance system for a large company with multiple branches. It will use an IP-based surveillance system with network cameras, switches, and PCs. The system will utilize a content management system, towers for wireless connectivity, digital video recorders, network video recorders, and network attached storage. Fiber optic or UTP cables will connect the cameras. Protocols like UDP, RTSP, and RTP will be used to transmit video. Limitations include high costs, centralized storage, and fiber optic cable installation challenges.
JAVA 2013 IEEE CLOUDCOMPUTING PROJECT Attribute based encryption with verifia...IEEEGLOBALSOFTTECHNOLOGIES
This document summarizes an academic paper that proposes an attribute-based encryption scheme with verifiable outsourced decryption. Existing schemes offload decryption to an untrusted server but do not verify the correctness of the transformation. The proposed scheme modifies the security model to allow for verification and constructs a concrete ABE system where a user can efficiently check that the server performed the decryption transformation correctly, without relying on random oracles. The scheme substantially reduces the computation required for decryption on resource-limited devices.
Attribute based encryption with verifiable outsourced decryptionIEEEFINALYEARPROJECTS
To Get any Project for CSE, IT ECE, EEE Contact Me @ 09849539085, 09966235788 or mail us - ieeefinalsemprojects@gmail.co¬m-Visit Our Website: www.finalyearprojects.org
The document provides an overview of MPEG-4, a standard that offers both advanced audio and video codecs as well as tools for combining multimedia such as audio, video, graphics and interactivity. It was developed through an open international process to select the best technologies. MPEG-4 codecs like AVC and AAC provide high compression efficiency, having been adopted for HDTV, mobile video, and digital music. Its rich media tools allow interactive experiences combining different media types.
This document provides an overview of Codan's 6700/6900 series block up converter (BUC) systems and components. It describes the BUC, low-noise block converter (LNB), and redundancy systems. It also covers installation, operation, and troubleshooting of the systems. The document contains information on frequency bands, conversion plans, interfaces, cable connections, monitor/control, commands, maintenance procedures, and compliance standards.
This document discusses digital set-top boxes (STBs) and related standards. It covers:
1) The DVB standards for digital TV broadcasting via different transmission media, including DVB-T for terrestrial, DVB-S for satellite, and DVB-C for cable. These share source coding/compression and service multiplexing standards.
2) STBs will be needed until integrated digital TVs are cheaper. Affordable STBs are key for digital TV adoption. Common standards help lower STB costs through economies of scale.
3) "Open architecture" and "interoperability" mean the STB functionality is defined by public standards and can receive services across networks, respectively. The
The document discusses DCT/IDCT concepts and applications. It provides an introduction to DCT and IDCT, explaining that they are used widely in video and audio compression. It describes the DCT and IDCT functions and how they work to transform signals between spatial and frequency domains. Examples of one-dimensional and two-dimensional DCT/IDCT equations are also given. Finally, common applications of DCT/IDCT compression techniques are listed, such as in DVD players, cable TV, graphics cards, and medical imaging systems.
This document discusses image compression using the discrete cosine transform (DCT). It develops simple Mathematica functions to compute the 1D and 2D DCT. The 1D DCT transforms a list of real numbers into elementary frequency components. It is computed via matrix multiplication or using the discrete Fourier transform with twiddle factors. The 2D DCT applies the 1D DCT to rows and then columns of an image, making it separable. These functions illustrate how Mathematica can be used to prototype image processing algorithms.
DVB-S2 is the second-generation specification for satellite broadcasting developed by DVB in 2003. It uses more advanced channel coding (LDPC codes) and modulation formats (QPSK, 8PSK, 16APSK, 32APSK) for a 30% increase in transmission capacity over DVB-S. DVB-S2 allows for adaptive coding and modulation to optimize transmission for each user. It is designed for broadcast, interactive, and professional applications with flexibility to handle different transponder characteristics and content formats.
The STi7167 is an integrated system-on-chip that combines a configurable DVB-T or DVB-C demodulator with STB decoding and display functions. It provides advanced HD and SD video decoding, audio decoding, graphics processing, and connectivity options. The chip's integrated features allow for low cost and small size STB designs for cable or terrestrial networks.
This document provides an overview of service information (SI) in digital video broadcasting (DVB) systems, including sections like the network information section (NIT), service description section (SDT), bouquet association section (BAT), program association section (PAT), conditional access section (CAT), transport stream description section (TSDT), event information section (EIT), and running status section (RST). It includes syntax diagrams and details for each section, such as table IDs, section lengths, descriptors, and other fields. It also provides the PID and refresh interval requirements for each table type.
1) The document describes a modification to the Huffman coding used in JPEG image compression. It proposes pairing each non-zero DCT coefficient with the run-length of subsequent (rather than preceding) zero coefficients.
2) This allows using separate optimized Huffman code tables for each DCT coefficient position, improving compression by 10-15% over standard JPEG coding.
3) The decoding procedure is not changed and no end-of-block marker is needed, providing advantages with no increase in complexity.
Dani Pedrosa won the MotoGP race at Laguna Seca, finishing just 0.344 seconds ahead of Valentino Rossi in second and 1.926 seconds ahead of Jorge Lorenzo in third. Casey Stoner finished fourth, over 12 seconds behind Pedrosa. There were several crashes during the race, with Andrea Dovizioso, Sete Gibernau, and Gabor Talmacsi all falling out of contention. James Toseland received a ride through penalty for a jump start.
The document provides implementation guidelines for using the DVB Simulcrypt standard, including describing the architecture and protocols, clarifying differences between protocol versions, explaining state diagrams and behaviors, and providing recommendations for error handling, redundancy management, and custom signaling profiles to facilitate reliable and efficient Simulcrypt headend implementation.
1) The document discusses quantization and pulse code modulation (PCM) in voice signal encoding. PCM assigns 256 possible values to digitally represent analog voice samples, divided into chords and steps on a linear scale.
2) A logarithmic quantization scale is better than a linear one for voice signals, as it allocates more quantization steps to lower amplitudes prevalent in speech. This "compressed encoding" improves fidelity.
3) Quantization error occurs when samples with different amplitudes are assigned the same digital value, distorting the reconstructed waveform. Compression helps maintain a higher signal-to-noise ratio especially for low amplitudes.
This document provides implementation guidelines for the DVB Simulcrypt standard. It describes the architecture and protocols involved in simulcrypt systems, including the ECMG protocol between the security client system and conditional access modules, and the EMMG/PDG protocol between conditional access modules and multiplex equipment. The document outlines differences between version 1 and 2 of the standards, and provides recommendations for compliance. It also includes detailed state diagrams and descriptions of the protocols involved.
The Event Logger monitors and logs Digital Program Insertion (DPI) messages to verify correct transmission of signals via satellite. It watches for configured GPI state changes that indicate an expected DPI message. If the message is received on time, it is logged as a matched event. If not received on time, it is flagged as missed. The Event Logger also decodes DPI messages to help diagnose issues, and is compatible with various encoding systems. It has 6 ASI inputs, 108 GPI sensors, and logs data in real-time and for archiving.
This document discusses the basics of BISS scrambling. It describes BISS mode 1, which uses a session word, and BISS mode E, which encrypts the session word using an identifier and encryption algorithm. BISS mode E provides an additional layer of protection for transmitting the session word. The document also covers calculating the encrypted session word, using buried and injected identifiers, and how to operate scramblers in the different BISS modes.
Euler's theorem states that for any plane graph, the number of vertices (v) minus the number of edges (e) plus the number of faces (f) equals 2. The document proves this theorem by considering a minimal tree (T) within the graph and its dual tree (D), showing that the number of edges of T and D sum to the total edges (e) of the original graph. Some applications of the theorem are that any plane graph contains an edge of degree 5 or higher and any finite set of points not all on a line contains a line with exactly two points.
This document provides an overview of satellite communications fundamentals. It discusses how satellites provide capabilities not available through landlines, such as mobility and quick implementation. However, satellites are not always the most cost effective solution due to limited frequency spectrum and spatial capacity. The document describes different types of satellite services and configurations, including geostationary and non-geostationary satellites. It also covers topics like frequency reuse, earth station antennas, and satellite link delays.
The document discusses quantization in analog-to-digital conversion. It describes the three processes of A/D conversion as sampling, quantization, and binary encoding. Quantization involves mapping amplitude values into a set of discrete values using a quantization interval or step size. The document discusses uniform quantization and how the quantization levels are determined. It also covers non-uniform quantization and provides examples and MATLAB code demonstrations of audio signal quantization.
1) Reed-Solomon codes are a type of error-correcting code invented in 1960 that can detect and correct multiple symbol errors. They work by encoding data into redundant symbols that can be used to detect and locate errors.
2) Reed-Solomon codes are particularly good at correcting burst errors, where a block of symbols are corrupted together by noise. Even if an entire block of bits is corrupted, the code can still correct the errors by replacing the corrupted symbol.
3) The error correction capability of Reed-Solomon codes increases with larger block sizes, as noise is averaged over more symbols. However, implementing Reed-Solomon codes also becomes more complex with higher redundancy.
This document describes the head-end architecture and synchronization for digital video broadcasting using SimulCrypt. It outlines the system components including an event information scheduler, SimulCrypt synchronizer, entitlement control message generator, entitlement management message generator, and multiplexer. It also describes the interfaces between these components, covering processes like channel and stream establishment and closure, as well as bandwidth allocation and status reporting.
Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
OpenID AuthZEN Interop Read Out - AuthorizationDavid Brossard
During Identiverse 2024 and EIC 2024, members of the OpenID AuthZEN WG got together and demoed their authorization endpoints conforming to the AuthZEN API
CAKE: Sharing Slices of Confidential Data on BlockchainClaudio Di Ciccio
Presented at the CAiSE 2024 Forum, Intelligent Information Systems, June 6th, Limassol, Cyprus.
Synopsis: Cooperative information systems typically involve various entities in a collaborative process within a distributed environment. Blockchain technology offers a mechanism for automating such processes, even when only partial trust exists among participants. The data stored on the blockchain is replicated across all nodes in the network, ensuring accessibility to all participants. While this aspect facilitates traceability, integrity, and persistence, it poses challenges for adopting public blockchains in enterprise settings due to confidentiality issues. In this paper, we present a software tool named Control Access via Key Encryption (CAKE), designed to ensure data confidentiality in scenarios involving public blockchains. After outlining its core components and functionalities, we showcase the application of CAKE in the context of a real-world cyber-security project within the logistics domain.
Paper: https://doi.org/10.1007/978-3-031-61000-4_16
Generating privacy-protected synthetic data using Secludy and MilvusZilliz
During this demo, the founders of Secludy will demonstrate how their system utilizes Milvus to store and manipulate embeddings for generating privacy-protected synthetic data. Their approach not only maintains the confidentiality of the original data but also enhances the utility and scalability of LLMs under privacy constraints. Attendees, including machine learning engineers, data scientists, and data managers, will witness first-hand how Secludy's integration with Milvus empowers organizations to harness the power of LLMs securely and efficiently.
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfMalak Abu Hammad
Discover how MongoDB Atlas and vector search technology can revolutionize your application's search capabilities. This comprehensive presentation covers:
* What is Vector Search?
* Importance and benefits of vector search
* Practical use cases across various industries
* Step-by-step implementation guide
* Live demos with code snippets
* Enhancing LLM capabilities with vector search
* Best practices and optimization strategies
Perfect for developers, AI enthusiasts, and tech leaders. Learn how to leverage MongoDB Atlas to deliver highly relevant, context-aware search results, transforming your data retrieval process. Stay ahead in tech innovation and maximize the potential of your applications.
#MongoDB #VectorSearch #AI #SemanticSearch #TechInnovation #DataScience #LLM #MachineLearning #SearchTechnology
“An Outlook of the Ongoing and Future Relationship between Blockchain Technologies and Process-aware Information Systems.” Invited talk at the joint workshop on Blockchain for Information Systems (BC4IS) and Blockchain for Trusted Data Sharing (B4TDS), co-located with with the 36th International Conference on Advanced Information Systems Engineering (CAiSE), 3 June 2024, Limassol, Cyprus.
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
Full-RAG: A modern architecture for hyper-personalizationZilliz
Mike Del Balso, CEO & Co-Founder at Tecton, presents "Full RAG," a novel approach to AI recommendation systems, aiming to push beyond the limitations of traditional models through a deep integration of contextual insights and real-time data, leveraging the Retrieval-Augmented Generation architecture. This talk will outline Full RAG's potential to significantly enhance personalization, address engineering challenges such as data management and model training, and introduce data enrichment with reranking as a key solution. Attendees will gain crucial insights into the importance of hyperpersonalization in AI, the capabilities of Full RAG for advanced personalization, and strategies for managing complex data integrations for deploying cutting-edge AI solutions.
Best 20 SEO Techniques To Improve Website Visibility In SERPPixlogix Infotech
Boost your website's visibility with proven SEO techniques! Our latest blog dives into essential strategies to enhance your online presence, increase traffic, and rank higher on search engines. From keyword optimization to quality content creation, learn how to make your site stand out in the crowded digital landscape. Discover actionable tips and expert insights to elevate your SEO game.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
Unlocking Productivity: Leveraging the Potential of Copilot in Microsoft 365, a presentation by Christoforos Vlachos, Senior Solutions Manager – Modern Workplace, Uni Systems
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?Speck&Tech
ABSTRACT: A prima vista, un mattoncino Lego e la backdoor XZ potrebbero avere in comune il fatto di essere entrambi blocchi di costruzione, o dipendenze di progetti creativi e software. La realtà è che un mattoncino Lego e il caso della backdoor XZ hanno molto di più di tutto ciò in comune.
Partecipate alla presentazione per immergervi in una storia di interoperabilità, standard e formati aperti, per poi discutere del ruolo importante che i contributori hanno in una comunità open source sostenibile.
BIO: Sostenitrice del software libero e dei formati standard e aperti. È stata un membro attivo dei progetti Fedora e openSUSE e ha co-fondato l'Associazione LibreItalia dove è stata coinvolta in diversi eventi, migrazioni e formazione relativi a LibreOffice. In precedenza ha lavorato a migrazioni e corsi di formazione su LibreOffice per diverse amministrazioni pubbliche e privati. Da gennaio 2020 lavora in SUSE come Software Release Engineer per Uyuni e SUSE Manager e quando non segue la sua passione per i computer e per Geeko coltiva la sua curiosità per l'astronomia (da cui deriva il suo nickname deneb_alpha).
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?
conditional access system
1. Functional model of a
conditional access system
EBU Project Group B/CA
EBU Project Group B/CA has
developed a functional model of a
conditional access system for use
with digital television broadcasts. It
should be of benefit to EBU
Members who intend to introduce
encrypted digital broadcasts; by
using this reference model,
Members will be able to evaluate the
different conditional access systems
that are available.
1. Introduction The model is not intended as a
A conditional access (CA) system comprises a specification for a particular system.
combination of scrambling and encryption to Rather, it provides a framework for
prevent unauthorized reception. Scrambling is the defining the terms and operating
process of rendering the sound, pictures and data principles of conditional access
unintelligible. Encryption is the process of pro- systems and it illustrates some of the
tecting the secret keys that have to be transmitted conflicts and trade-offs that occur
with the scrambled signal in order for the when designing such systems.
descrambler to work. After descrambling, any
defects on the sound and pictures should be
imperceptible, i.e. the CA system should be trans-
parent. – to enforce payments by viewers who want ac-
cess to particular programmes or programme
The primary purpose of a CA system for broad- services;
casting is to determine which individual receivers/
set-top decoders shall be able to deliver particular – to restrict access to a particular geographical
programme services, or individual programmes, to area because of programme-rights consider-
Original language: English
the viewers. The reasons why access may need to ations (territorial control can be enforced if the
Manuscript received 6/10/95. be restricted include: receiver has a built-in GPS system);
64 EBU Technical Review Winter 1995
EBU Project Group B/CA
2. Glossary
Access Control System/Conditional Access System: The Pay-Per-View (PPV): A payment system whereby the
complete system for ensuring that broadcasting services are viewer can pay for individual programmes rather than take
only accessible to those who are entitled to receive them. out a period subscription. Pay-Per-View can work by debiting
The system usually consists of three main parts – signal electronic credit stored in a smart card, by purchasing smart
scrambling, the encryption of the electronic “keys” needed by cards issued for special programmes, or by electronic
the viewer, and the subscriber management system which banking using a telephone line to carry debiting information
ensures that viewers entitled to watch the scrambled from the home to the bank.
programmes are enabled to do so.
Period Subscription: The most popular payment system, in
Algorithm: A mathematical process (e.g. DES, RSA) which which the viewer subscribes to a programme service for a
can be used for scrambling and descrambling a data stream. calendar period (e.g. one year).
Bouquet: A collection of services marketed as a single Piracy: Unauthorized access to controlled programmes.
entity. Common methods of piracy include the issue of counterfeit
Conditional Access Sub-System (CASS): The part of the smart cards and decoders which bypass all or part of the
decoder which is concerned with decoding the electronic access control system. The use of video cassette recorders
keys, and recovering the information needed to control the to record descrambled pictures for distribution among
descrambling sequence. It is now usually implemented, all or friends/colleagues is also a simple method of piracy.
in part, as a smart card. Programme: A television (or radio) presentation produced
Control Word: The key used in the descrambler. by programme providers for broadcasting as one of a
sequence. A programme is a grouping of one or more events.
Descrambling: The process of undoing the scrambling to
yield intelligible pictures, sound and/or data services. Scrambling: The method of continually changing the form of
the broadcast signal so that, without a suitable decoder and
Electronic key: A general term for the data signals used to electronic key, the signal is unintelligible.
control the descrambling process in the decoders. There are
several different levels of key, identifying the network which Service: A sequence of events, programmes or data, based
the subscriber is entitled to access, the services within that on a schedule, assembled by a service provider to be
network that are available to the subscriber and the detailed delivered to the viewer.
control information to operate the descrambler. The ECMs
SimulCrypt: A system for allowing scrambled picture/sound
are one component of this “key” data; all levels must be
signals to be received by decoders using different access
correctly decrypted in order to view the programme.
control systems. The principle of the system is that the
Encryption: The method of processing the continually- different ECMs and EMMs needed for the various access
changing electronic keys needed to descramble the control systems are sent over-air together. Any one decoder
broadcast signals, so that they can be securely conveyed to picks out the information it needs and ignores the other
the authorized users, either over-the-air or on smart cards. codes. It is analagous to providing multiple front doors to a
large house, each with a different lock and its own door key.
Entitlement Control Message (ECM): A cryptogram of the
control word and the access conditions. An ECM is a Smart Card: A device that looks rather like a credit card; it is
specific component of the electronic key signal and used as a token of entitlement to descramble broadcast
over-the-air addressing information. The ECMs are used to signals. Most of the major European access control systems
control the descrambler and are transmitted over-air in use smart cards. Other systems that bury the same
encrypted form. functionality inside the decoder do not usually allow the
system to be changed to combat piracy or to add new
Entitlement Management Message (EMM): A message services. Smart cards can be issued by the Subscriber
authorizing a viewer to descramble a service. An EMM is a Management System which can validate them by
specific component of the electronic key signal and pre-programming them with keys to authorize access to
over-the-air addressing information. The EMMs are used to certain tiers of programmes and/or data services. As part of
switch individual decoders, or groups of decoders, on or off the same issuing and validation process, the card may be
and are transmitted over-air in encrypted form. personalised to make each one valid for one particular
Event: A grouping of elementary broadcast data streams decoder only.
with a defined start and time (e.g. an advert or a news flash).
Subscriber Authorization System (SAS): The centre
Impulse Pay-Per-View: Impulse Pay-Per-View requires no responsible for organizing, sequencing and delivering EMM
pre-booking. This rules out some Pay-Per-View methods and ECM data streams under direction from the Subscriber
(e.g. issuing smart cards for specific programmes). Smart Management System.
card debit, or electronic banking via telephone line, both
support impulse Pay-Per-View. Over-the-air addressing can Subscriber Management System (SMS): The business
support impulse PPV, provided that the time taken to process centre which issues the smart cards, sends out bills and
the request is sufficiently small (this implies a relatively large receives payments from subscribers. An important resource
capacity for over-the-air addressing data in the transmission of the Subscriber Management System is a database of
channel. infromation about the subscribers, the serial numbers of the
decoders and information about the services to which they
Multiplex: An assembly of all the digital data that is carrying have subscribed. In commercial terms, this information is
one or more services within a single physical channel. highly sensitive.
EBU Technical Review Winter 1995 65
EBU Project Group B/CA
3. Figure 1
Vertically-integrated Service Transmission Viewers/
SMS SAS
provider system operator IRDs
CA system.
Service
Transmission Viewers/
provider SMS SAS
system operator IRDs
A
Figure 2
Devolved CA system.
Service
provider
B
Service
SMS SAS Transmission Viewers/
provider
X I system operator IRDs
A
Figure 3 Service
Devolved/shared/common SMS SAS
provider
CA system. Y J
B
Service
SMS
provider
Z
C
KEY: Programmes SMS = Subscriber Management System
SAS = Subscriber Authorization System
Entitlements to view IRD = Integrated Receiver Decoder
Money, addresses and bills
Money and addresses
66 EBU Technical Review Winter 1995
EBU Project Group B/CA
4. – to facilitate parental control (i.e. to restrict the names, addresses and entitlement status of
access to certain categories of programme2). viewers to their own services.
An alternative model of a devolved CA system is
2. Transactional models shown in Fig. 3. Here, there are two independent
Transactional models can be used to illustrate the CA Subscriber Authorization System (SAS) oper-
underlying commercial transactions that take ators, I and J (see Section 5.3.). System J is used
place in a conditional access broadcasting system, by service provider C only, whereas system I is
in a way which is independent of the technology used by all three service providers. Conversely,
employed. A similar analogy is sometimes used service providers A and B use system I only,
for the sale of goods to the public through retail and whereas service provider C uses systems I and J.
wholesale chains: in that situation, there is a flow Thus, viewers to the services provided by C can
of goods and services in one direction – from the use a decoder which is appropriate for either
manufacturers to the end customers – and a flow of system I or J. A further feature of this model is that
money in the reverse direction. the billing and the money flow is directly between
the viewers and the Subscriber Management
A model of a vertically-integrated CA system is System (SMS) operators (see Section 5.3.); it does
shown in Fig. 1. Here, the service provider is also not pass via the SAS operators or the transmission
the network operator and the CA system operator. system operators. Consequently, sensitive in-
Historically, CA systems originated in this form formation about the names and addresses of sub-
and the model remains true for many cable scribers is known only to the appropriate service
systems today: the cable operator acts as the ser- provider.
vice provider (usually by purchasing the rights to
show programmes made by third parties) and also
3. Functional model of a CA
as the carrier and the CA system operator. In such
circumstances, and especially where – as in most reference system
cable systems – the cable operator supplies and A functional model of a hypothetical CA reference
owns the decoders, a single proprietary system is system is now described. The model is loosely
acceptable, because there is no requirement to based on the Eurocrypt conditional access system
share any part of the system with competitors. but its principles of operation are expected to apply
to CA systems generally.
A model of a devolved CA system is shown in
Fig. 2. In this case, the functions of the service
provider, network operator and CA system 3.1. Conditional Access
operator are split. Indeed, there are two separate Sub-System
service providers, A and B, who share a common A Conditional Access Sub-System (CASS) is a
delivery system (owned and operated by a third detachable security module which is used as part
party) and a common CA system which is owned of the CA system in a receiver. It is also possible
and operated by a different third party. Thus all to embed the security module in the receiver itself,
billing and collection of money is carried out by in which case each receiver will typically have its
the CA system operator who then passes on pay- own secret individual address. Replacement of the
ments in respect of programme rights back to the CASS is one means of recovering from a piracy at-
appropriate service providers. This model is true tack. Replacement of the CASS also enables new
for many analogue satellite systems today and features to be added to the system as and when they
also applies to a retail market in which there is are developed.
only one retailer. Note how the CA system opera-
tor has information about the names, addresses For analogue systems and some digital systems,
and entitlement status of all viewers; programme the CASS is typically a smart card [1]. For digital
providers, on the other hand, have access only to systems which use the Common Interface (see
Section 3.6.), the CASS will be a PCMCIA3 mod-
2. This is generally a Service Information (SI) function. ule and this may have an associated smart card.
However, regulators might specify that programmes
should be scrambled where parental control is required.
In current analogue systems, parental control often uses 3. Personal Computer Manufacturers Computer Interface
the CA system. Association.
EBU Technical Review Winter 1995 67
EBU Project Group B/CA
5. 3.2. Scrambling and descrambling are used to recover the descrambling control word
in the decoder – is illustrated in Fig. 5. The ECMs
The basic process of scrambling and descrambling are combined with a service key and the result is
the broadcast MPEG-2 transport stream [2] is decrypted to produce a control word. At present,
shown in Fig. 4. The European DVB Project has the control word is typically 60 bits long and is up-
defined a suitable, highly-secure, Common dated every 2-10 seconds.
Scrambling Algorithm.
If the access conditions are to be changed at a pro-
3.3. Entitlement Control Messages gramme boundary, it may be necessary to update
the access conditions every frame, which is much
The generation, transmission and application of more frequently than is required for security
Entitlement Control Messages (ECMs) – which reasons. Alternatively, a change in access condi-
Figure 4
Basic scrambling system.
Tx Rx
MPEG-2 MPEG-2
transport transport
Picture stream Picture
stream
Sound MUX Scrambler Modulator Demodulator Descrambler Demux Sound
Data Data
Note: In such a basic scrambling system, possession of a
descrambler gives permanent entitlement to view.
Figure 5
Scrambling system with
Encrypted Control Words.
Tx Rx
Picture Picture
Sound MUX Scrambler Modulator Demodulator Descrambler Demux Sound
Data Data
ECMs CW CW ECMs
Service
Encrypter Decrypter
key
Service
Control Word key
Note 1: Descrambling requires possession of a descrambler, a
generator
decrypter and the current service key.
Note 2: Decryption recovers the descrambling Control Words
(CW) from the Entitlement Control Messages (ECMs).
68 EBU Technical Review Winter 1995
EBU Project Group B/CA
6. tions could be made frame-specific by sending out over-air or by another route, e.g. via a telephone
a change in entitlements in advance and then insti- line. To retain the confidentiality of customer in-
gating the change with a flag. A third method formation, it is best that the card supplier delivers
would be to change the control word itself at a the smart cards direct to the Subscriber Manage-
programme boundary. However, the second and ment System (or another business centre which
third approaches would not allow a programme guarantees confidentiality) for mailing to the
producer to change the access conditions instanta- viewer (see Section 3.5.).
neously.
It is possible to supply the cards through retail out-
3.4. Entitlement Management lets as well, provided the retailer can guarantee
Messages confidentiality. In this situation, considerable care
has to be taken if the cards have been pre-
The generation, transmission, and application of authorized by the SAS, because such cards will be
Entitlement Management Messages (EMMs) by a worthwhile target for theft.
the Subscriber Authorization System is illustrated
in Fig 6. When using the CA Common Interface [3], in con-
juction with a PCMCIA module acting as the
The card supplier provides the CASS (usually a CASS, the descrambler is also situated in the
smart card) and then the SAS sends the EMMs CASS.
Figure 6
Scrambling system with
encrypted Control Words and
Entitlement Management
Messages.
Tx Rx
Picture Picture
Sound MUX Scrambler Modulator Demodulator Descrambler Demux Sound
Data Data
EMMs ECMs CW CW ECMs EMMs
Entitlement Management
Messages via telephone line
(and validation return)
Encrypter Encrypter Decrypter Decrypter
Service
Validation key
Subscriber Security
Control Word SMART card
Authorization processor
generator supplier
System (secret keys)
Conditional Access
Sub-System (CASS)
Note 1: Descrambling requires possession of a descrambler, a decrypter and the current
service key.
Note 2: Decryption requires the Entitlement Management Messages (EMMs) for the
current programme – which usually involves secret keys stored in a detachable
Conditional Access Sub-System (CASS).
EBU Technical Review Winter 1995 69
EBU Project Group B/CA
7. 3.5. Subscriber Management The CA system is contained in a low-priced, pro-
System prietary module which communicates with the
IRD via the Common Interface. No secret condi-
As shown in Fig 7., the reference model is com- tional access data passes across the interface.
pleted by the addition of a Subscriber Management
System (SMS), which deals with the billing of
The Common Interface allows broadcasters to use
viewers and the collection of their payments. The
CA modules which contain solutions from differ-
control word need not be a decrypted ECM; it can
ent suppliers, thus increasing their choice and anti-
be generated locally (e.g. from a seed) which
piracy options.
means that the control word could be changed very
quickly.
3.6. Common Interface 4. General requirements of a
CA system
The European DVB Project has designed a
Common Interface for use between the Integrated To be acceptable for use by EBU members, a
Receiver Decoder (IRD) and the CA system. As conditional access system needs to meet the fol-
shown in Fig. 8, the IRD contains only those ele- lowing general requirements, some of which con-
ments that are needed to receive clear broadcasts. flict.
Figure 7
Scrambling system with
encrypted Control Words,
Entitlement Management
Messages and Subscriber
Management System.
Tx Rx
Picture Picture
Sound MUX Scrambler Modulator Demodulator Descrambler Demux Sound
Data Data
EMMs ECMs CW CW ECMs EMMs
Entitlement Management
Messages via telephone line
(and validation return)
Encrypter Encrypter Decrypter Decrypter
Service
Validation key
Subscriber Security
Control Word SMART card
Authorization processor
generator supplier
System (secret keys)
Conditional Access
Sub-System (CASS)
Subscriber Bills
Management
System (SMS) Subscribers
(Customer
Management) Payments
(credit card, Direct Debit, cash, cheque, etc)
70 EBU Technical Review Winter 1995
EBU Project Group B/CA
8. DVB/MPEG integrated
receiver/decoder (IRD)
MPEG
video Picture
decoder
Tuner Demodulator Demux
MPEG
video Sound
MPEG-2 decoder
transport
stream Data
Validation
SI On-screen
module
decoder graphics
(optional)
Command Remote
Receiver control
bus input
operating system
DVB Common Interface
DVB CW
descrambler
Validation
(optional) Module
operating
system
Module
Data filters operating
(ECMs, EMMs) system
Security
processor
Figure 8
Proprietary SMART card
DVB Common
(optional)
CA system Interface.
4.1. Convenience for viewers bination of programme services to which
individual viewers had subscribed.
The CA system should impose a minimum of bur- It should be easy for the viewer to pay the neces-
den on the authorized viewer at any stage in the sary fees to the programme supplier. Payment
transaction. In particular it should not require methods should include all forms of monetary
special action when changing channels (e.g. transaction including cash, direct debits and credit
swapping a smart card or keying in a Personal cards. The viewer might prefer to receive a single
Identification Number) nor should it significantly bill for any combination of services provided over
delay presentation of picture and sound when a period of time. It may therefore be desirable, but
“zapping” (a sensible upper limit on the “zap- not a necessity, for different CA system operators
ping” time is 1 second). to share the use of smart cards.
4.2. Security
Furthermore, it should be easy to gain initial ac-
cess to the broadcasts, requiring the minimum of The CA system must be effective in preventing
equipment, outlay and effort. Ideally, the com- piracy, i.e. unauthorized viewing by people who are
plete system would be integrated into the televi- not entitled to access particular programmes or ser-
sion set which would be able to access any com- vices. Although no CA technology can deliver per-
EBU Technical Review Winter 1995 71
EBU Project Group B/CA
9. fect security, the overall system – combined with approved service providers have fair access to a
appropriate anti-piracy legislation and evasion- suitable delivery system.
deterrent measures – must make piracy sufficiently
difficult and/or uneconomic that the levels of 4.5. Autonomy of the service
evasion are kept small. Smart cards or payment provider’s business
cards must be resistant to tampering. For Pay-Per-
View services in particular, the counting mecha- The primary contract should be between the ser-
nism which indicates the remaining credit should be vice provider and the viewer. Although third parties
immune to resetting by unauthorized parties. (such as common carriers and/or CA system opera-
tors) may necessarily be involved in the broadcast-
It is very important that the relationship between ing process, the CA system (and any other part of
the service provider and the CA system operator is the system) should not require the service provider
well defined so that, for example, a CA system to share commercially-sensitive information with
operator can be compelled to act when piracy rival service providers, e.g. the identities of cus-
reaches a certain level. There are a number of ways tomers and their entitlements to view.
to recover from a piracy attack. It is possible to
initiate electronic counter measures over-air, 4.6. Low entry and operating costs
whereby pirate cards are disabled or subtle changes The cost of setting up and operating the CA system
are made in the operation of genuine CASSs. Alter- is significant but must not be prohibitive. In particu-
natively, by issuing new CASSs, large changes can lar, it should be capable of being scaled to allow low
be made to the conditional access system. start-up costs when the subscriber base is very small.
4.3. Open marketing of digital The system should not pose a constraint on the ulti-
receivers mate number of households that can be addressed;
this could reach many tens of millions. The costs
The viewers should be able to benefit from a large of upgrades to the CA system and of recovering
choice of digital receivers or set-top boxes, from security breaches should be minimized by
produced by a wide range of manufacturers com- selecting a reliable and secure system.
peting in an open market. Such an open market
ideally requires that the complete digital broad-
casting system, excluding the CA system, be fully 5. Functional requirements of
described in open standards which are fully pub- a CA system
lished by the appropriate organization (e.g. the
ETSI 4 or the ISO5). The terms of licensing any 5.1. Payment schemes
Intellectual Property Rights (IPR) included with-
It is important that the CA system supports a wide
in a standard must be regulated by the appropriate
range of charging and payment schemes.
standards organization. (For example, in the case
of an ETSI standard, licensing is open to all These include:
manufacturers on an equitable basis.)
– Subscription (pre-payment for a time period of
It is undesirable for the CA system to be standard- viewing);
ized: instead, the flexibility offered by the DVB – Pay-Per-View (payment for a programme or
Common Interface should ensure that a plurality of group of programmes);
CA systems may be adopted (see Section 3.6.).
– Impulse Pay-Per-View (payment for a pro-
4.4. Open marketing of programme gramme or group of programmes without
services advance notice).
Pay-Per-View (PPV) and Impulse Pay-Per-View
Authorized programme services should be acces-
(IPPV) often require the provision of a return path
sible to any viewer whose IRD conforms to the
from the viewer to the CA system operator: in
relevant standard and who has the relevant CA en-
many systems this is implemented using a tele-
titlements issued solely under the control of the
phone connection and a modem built into the
service provider. It must also be ensured that all
IRD. The return path can be used to record view-
ing history, which is important when considering
the programme rights issues.
4. European Telecommunications Standards Institute. The acceptability and rules of operation for such a
5. International Organisation for Standardisation. telephone return-path need further study. In par-
72 EBU Technical Review Winter 1995
EBU Project Group B/CA
10. ticular, a system must exist for those viewers who pendent zones so that operators have access to
do not have a telephone connection. One possible write to and read from only those zones which con-
method would be to purchase credits in advance tain information about entitlements to view their
and to store them as viewing tokens on a smart card own services. Where operators share a security
or CA module. The card or module could be re- device, it is important to resolve who issues and,
authorized at a trusted dealer when information on more importantly, who re-issues the security de-
past viewing could be transferred to the system vice – especially in the case of a breach of security
operator. Provided security was not compromised, requiring a change of security device.
it would also be possible to have the smart card or
module credited over-air with tokens which could A particularly important and difficult requirement
be initiated by a telephoned (voice) request from which arises from the need to share decoders is that
the viewer. There must be a method to ensure that of allowing the IRD to be tuned to broadcasts
all service providers are paid fairly for the pro- which do not necessarily carry the same over-air
grammes provided, in proportion to the total num- entitlement messages. It is worthwhile monitoring
ber of viewer hours. as many EMM data streams as possible, even when
the receiver is in standby mode.
5.2. Multiple-decoder households
In some instances (for example, message broadcast-
The question must be addressed as to whether pay- ing), it is necessary for the broadcaster to be able to
ment authorizes: address large numbers of decoders in a short period
of time. In these situations, it is worth using shared
1. the use of only one decoder to receive and keys to reduce the access time for large audiences.
decode the services; The audience is subdivided into groups of viewers;
each person within a particular group has the same
2. use throughout a household, which may have
shared key which forms a part of the overall control
multiple receivers/decoders and a VCR;
word. Also, different messages intended for the
3. use by one individual anywhere within a house- same viewer can be combined together.
hold, in which case the entitlement needs to be
transferable from one IRD to another, probably 5.3.2. Delivery system
using a detachable security element such as a
smart card. It is obvious that any one delivery medium (e.g.
cable network, satellite transponder or terrestrial
In the third case given above, there is a conflict broadcast channel) should be capable of being
with the requirement to validate the security de- shared between different and perhaps rival broad-
vice for use with a particular decoder only. There- casters. Less obvious, but perhaps equally impor-
fore, each decoder should have its own CASS and tant, is that any one transport stream should be
the records of multiple CASSs within a household capable of being decoded by different types of de-
should be grouped together in the SMS to permit coder, so that one broadcast can simultaneously
appropriate and reasonable billing. use different kinds of CA system. This is the
SimulCrypt concept (see Section 7.1.1.).
5.3. Sharing of the CA system
5.3.3. CA Systems
In order to provide a fair and open market for CA
broadcasts to develop, it is important that elements When considering the sharing of CA systems at
of the CA system can be shared. These include the the sending end, it is important to be able to divide
following. the system into two separate functional elements:
a) Subscriber Management System (SMS)
5.3.1. Receivers/decoders
The SMS is primarily responsible for sending
One generic receiver/decoder should be capable out bills and receiving payments from viewers.
of receiving and decoding CA broadcasts from a It does not need to, and should not, be specific
number of different broadcasters, perhaps using to a particular CA system. The SMS necessarily
different delivery media (e.g. cable, satellite, ter- holds commercially-sensitive information such
restrial). This may imply that the decoder can sup- as the database of subscribers names and ad-
port simultaneous use of multiple security devices, dresses and their entitlement status. Sharing of
or that one security device can be shared between the SMS between rival broadcasters is possible
different service providers. In the latter case, the if, and only if, it is operated by a trusted third
security device needs to be partitioned into inde- party and only if adequate “firewalls” are pro-
EBU Technical Review Winter 1995 73
EBU Project Group B/CA
11. vided so that any one service provider can ac- which the system will not be usable. Disable
cess information only about subscribers to his messages may have an indefinite lifetime
or her own services. Although sharing an SMS whereas enable messages may have a lifetime
may be seen as undesirable, it must be recog- of a month or so. For security reasons, commu-
nised that setting up and running an SMS is ex- nication between the SMS and the SAS can be
pensive, perhaps prohibitively so for services encrypted although this may not be necessary if
with a small number of subscribers at the outset. all systems are in a secure environment.
The work of the SMS can be contracted out to 5.4. Transcontrol at media
a trusted third party (TTP), e.g. a secure and boundaries
reliable organization such as a bank. There
should be a subscriber database and the system It will often be the case that a broadcast signal may
must deal with changes to subscription details, travel via two or more different delivery media in
installation difficulties, marketing, billing and tandem; for example the broadcast may be carried
card distribution. The SMS also manages the on a satellite and then conveyed into some homes
system installers and sends Entitlement Man- via a cable system. In such cases it is often desir-
agement Messages (to authorize viewers) to the able to change the entitlement control at the media
Subscriber Authorization System queue. boundary without needing to descramble and re-
scramble completely. (This is possible with the use
To ensure the privacy of customer database
of the Common Scrambling Algorithm.) Howev-
information, the SMS could mail replacement
er, this method may present a security risk because
smart cards and CA modules to the viewers.
one CA system operator would have to present the
These could be provided pre-authorized by the
control word to another CA system operator inside
conditional access system operator or could be
the transcontrol equipment.
authorized over-air by the Subscriber Autho-
rization System using virtual addresses pro-
vided by the SMS. In practice it may be more secure (though more
expensive) to descramble and rescramble at the
At the moment, cable companies often send out media boundary. Descramblers and rescramblers
a tape of customer usage to another company, at from different CA system manufacturers could
the end of the month, for billing. potentially be built into different PCMCIA modules.
b) Subscriber Authorization System Changing the entitlement control at the media
The Subscriber Authorization System (SAS) is boundary enables the end-transmission-system-
primarily responsible for sending out the over- operators to maintain direct control over each of
air entitlement messages and for validating their subscribers for all services provided. This
security devices. The SAS needs a unique serial means that the viewer only has to operate the CA
number (address) for each IRD security device system used by the end-transmission-system-
but should not need access to commercially- operator. However, this approach also means that
sensitive information such as the names and the service providers and the other transmission-
addresses of subscribers. Hence it should be system-operators that have supplied services to the
easily possible for rival broadcasters to share an end-transmission-system-operator cannot have di-
SAS, although there are issues to be resolved rect and exclusive interaction with the subscribers.
concerning the queuing times for messages.
Smart cards can be indirectly authorized over- Another approach would be to have no transcon-
air by the SAS. trol at media boundaries. The viewer would have
access to all services using either the SimulCrypt
The SAS generates a scrambler control word, or MultiCrypt approaches. This has the disadvan-
encrypts the conditional access data, queues tage to the end-transmission-system-operator that
and prioritises the Entitlement Management all control is handed over to the original CA system
Messages from the Subscriber Management operator and it therefore requires a good working
System, and scrambles the pictures and sound. relationship between all parties.
New messages from the SMS join the immedi-
ate queue, to be transmitted as soon as possible,
and also join a regular cyclic queue where they 6. Operational requirements
stay until they expire. The frequency of trans- of a CA system
mission depends on the length of the queue and
messages are expired by category. There will be For security reasons it is important to include at
a maximum limit on response time beyond least the following functions in a CA system:
74 EBU Technical Review Winter 1995
EBU Project Group B/CA
12. – Disable/enable decoder 7. System implementation
Individual decoders or groups of decoders are 7.1. Satellite transmission
prevented from descrambling any service, re-
gardless of the authorizations stored in the The DVB Project has given its backing to two CA
smart card or other security device. approaches for the transmission of digital televi-
sion via satellite, namely SimulCrypt and Multi-
– Disable/enable card Crypt. These approaches are also relevant in cable
Individual smart cards, or groups of smart cards and terrestrial transmission.
(or other security devices), need to be capable
of being enabled or disabled over-air. 7.1.1. SimulCrypt
– Disable/enable programme service In the case of SimulCrypt, each service is trans-
mitted with the entitlement messages for a number
Individual smart cards, or groups of smart of different proprietary systems, so that decoders
cards, need to be capable of being enabled or using different conditional access systems (in dif-
disabled over-air to decode any one particular ferent geographic areas) can decode the service.
programme service. SimulCrypt requires a common framework for
signalling the different Entitlement Message
– Send message to decoder streams. Access to the system is controlled by the
A text message is sent to individual decoders or system operators. Operation of the system re-
groups of decoders for display on the screen; quires commercial negotiations between broad-
alternatively, the over-air message may com- casters and conditional access operators. A code
prise a display command and address of a mes- of conduct has been drawn up for the operation of
sage which is pre-stored in the decoder or smart SimulCrypt.
card, e.g. to warn of imminent expiry or to
The philosophy behind the system is that in one
request the viewer to contact the SMS because
geographical area, it will only be necessary to
of account difficulties.
have a single smart card or CA module and a single
– Send message to decoder for individual decoder to receive the local service. If one wanted
programme service to descramble the service of a neighbouring area,
one could subscribe to, and use the smart card/
A text message is sent to individual decoders or module for that service. Consequently, it is only
groups of decoders in the same way as above, necessary to have a single Subscriber Management
but is displayed only when the receiver/decoder System for a given area. When a viewer wants to
selects the relevant programme service. watch services from two neighbouring areas, it is
– Show customer’s ID card necessary for both services to carry the entitlement
messages for that viewer. Therefore it is necessary
The serial number of the smart card, or other to have secure links between the different Sub-
means of identification (ID), is displayed on the scriber Management Systems of the different
screen. This is not the secret ID contained with- operators to allow transfer of the entitlement mes-
in the card, but is an unprotected ID which sages between operators.
could be printed on the card. This function is
useful for maintenance procedures. 7.1.2. MultiCrypt
– Alter switching and drop-dead dates MultiCrypt is an open system which allows com-
petition between conditional access system pro-
An important security feature is that the algo- viders and Subscriber Management System opera-
rithms used to decrypt the over-air entitlement tors. MultiCrypt uses common receiver/decoder
messages and derive the descrambling control elements which could be built into television sets.
words can be changed. To allow smooth transi- The Common Conditional Access Interface can be
tion from one set of algorithms to the next, it is used to implement MultiCrypt. Conditional ac-
helpful if the smart card (or other security de- cess modules from different system operators can
vice) can store both algorithms and a date for be plugged into different slots in the common
switching from one to the other; this switching receiver/decoder, using the common interface.
date can be alterable over-air. There should also
be a “drop dead” date beyond which the card will 7.2. Return path
cease to function at all. Note that not all CA sys-
tems perform these functions in this way and the For most home installations, a return path could be
implementation may be very system-dependent. set up between the set-top decoder and the Sub-
EBU Technical Review Winter 1995 75
EBU Project Group B/CA
13. scriber Management System using a modem and return path could also be used to check that the
the telephone network or a cable TV return. For decoder is tuned to the correct channel when
example, calls could be initiated by the customer giving authorization over-air. This could re-
using a remote control unit which auto-dials a duce the number of over-air signals that had to
number delivered over-air. Also, the broadcaster be repeated perpetually.
may want the customer’s decoder box to contact
the SMS. This process could be initiated by com- 7.2.2. Reasons for not using a return
mands sent over-air or (less likely) the SMS could path
dial up the customer’s decoder box and interro-
gate it directly. There are also a number of reasons for not using a
return path, as follows:
7.2.1. Reasons for using a return path a) Increased decoder cost;
There are a number of reasons for using a return b) Installation difficulties;
path:
The customer may not have a telephone at all, or
a) Enhanced security; may not have a telephone in the relevant room (in
which case an extension socket would have to be
The return path establishes a one-to-one link fitted or a “cordless” connection would have to
between the broadcaster and each decoder box. be used which would increase costs).
Communication via the return path should be
encrypted. c) Reliability of the telephone;
b) Payment billing; In some areas, the reliability of the telephone
service may be an issue.
Pre-booked Pay-Per-View (PPV) and impulse
PPV could be registered using the return path. d) Blocking of normal calls;
Also, electronic viewing tokens could be pur- When the decoder is communicating, it will not
chased via the return path. A central server with be possible to make or receive normal telephone
a gateway would be necessary as a buffer for the calls, unless there is more than one telephone
large numbers of requests that would be ex- line to the house.
pected as part of a Pay-Per-View service. These
payment billing services could also be obtained e) Telephone tapping.
by the viewer dialling up the SMS using his con- Depending on how the communication system
ventional telephone and having a conversation works, there is a potential for reduced system
with an operator at the SMS. However this ap- security due to telephone tapping. Ideally, to
proach would be more time-consuming and overcome this problem, it is recommended that
costly to both the viewer and the SMS. the Subscriber Management System should re-
c) Interactive TV; turn the calls made by the IRD (although this
will increase the costs to the SMS), the commu-
The return path could be used for audience par- nication should be encrypted, and the Subscrib-
ticipation (for example voting, games playing, er Management System should be able to identi-
teleshopping and telebanking). The return path fy individual IRDs.
could also be used for message delivery from
the SMS to the decoder, although its limited Overall, the benefits of using a return path far ex-
bandwidth means that it is not very suitable for ceed the costs. In situations where the return path
more complicated procedures such as Video- does not exist but alternative facilities exist for per-
On-Demand (VOD). The return path could be forming some of its functions, decoders should be
used to deliver to the SMS diagnostic informa- manufactured which are capable of implementing
tion such as measurements of signal strength the return path. Cheaper decoders could be sold
and bit error rate (BER) to help solve transmis- which do not have this option installed.
sion problems, and other information such as a
record of programmes watched to provide sta- 7.3. Home video recorders
tistical information to the broadcaster.
If the viewer wants to watch one programme while
d) Transmission of entitlement messages.
recording another, then decisions will have to be
For large shared networks, the capacity for made about the payment approach for the service.
transmission of entitlement messages may be When using the Common Interface of the CA sys-
inadequate and additional capacity may be tem, it should be possible to descramble two chan-
achieved by using the telephone network. The nels on the same multiplex (one to watch and the
76 EBU Technical Review Winter 1995
EBU Project Group B/CA
14. other to record), using one PCMCIA module. To b) The second descrambler could also be used
descramble two channels on different multiplexes, if the viewer only owned an analogue video
one would need two PCMCIA modules, two tuners recorder.
and two MPEG-2 decoders.
In the video recorder
One approach would be to view the descrambled
a) The video recorder could be used on its own,
picture from one channel and to record the
without the need for a separate IRD box to
scrambled picture from another channel. The re-
record programmes;
corded picture could then be descrambled at view-
ing time and the appropriate charges could be made b) Any number of video recorders could be used
in a Pay-Per-View system. Copy protection could without the need for multiple IRD boxes.
be set for the digital recording. However, if the
DVTR does not record the encrypted data To reduce costs, the second descrambler could
associated with scrambling or, if the encryption initially be available as an optional add-on to the
mechanism would prevent successful descram- IRD box.
bling at the later replay time, it would be possible
to record an altered, but fixed, key. On replay, the
8. Conclusions and
picture could be descrambled using the fixed key,
which would be specific to a particular recorder. recommendations
This would help to ensure copyright protection by A basic set of transactional and functional models
preventing a scrambled picture on a tape from one of CA systems for use with digital video broadcast-
video recorder being descrambled by another ing systems has been outlined. These models are
video recorder. intended to help EBU Members to understand and
evaluate practical CA systems for use with future
Two descramblers could be used to permit the des- DVB services and, in particular, to understand the
crambling and recording of one programme whilst functionality, technical terms, and trade-offs in
watching another. This has the disadvantage of these systems. The specification or evaluation of
added cost and complexity. Copy protection a practical CA system requires considerably more
should be set for the original digital recording to depth and detail than could be included in this out-
hinder further digital recordings being made. line. In particular, an evaluation of security issues
requires a careful analysis of the overall system
The question then arises as to whether to locate the security, including non-technical issues such as the
second conditional access module in the IRD or in theft of data.
the video recorder. There are arguments in favour
of both options and there is no need to standardize
on one approach. In the end, the decision will be Acknowledgements
made by decoder and video recorder manufactur-
ers. When costs fall sufficiently, it is likely that EBU Project Group B/CA acknowledges a par-
top-of-the-range IRDs and video recorders will ticular debt of gratitude to Dr. S.R. Ely and Mr.
have descramblers installed. (If the initial costs of G.D. Plumb of BBC Research and Development
digital video recorders are very high, it may also be Department for their considerable contribution to
possible to buy analogue video recorders with the development of the reference model.
built-in descramblers).
The second descrambler/conditional access mod- Bibliography
ule could be installed either in the existing IRD
box, or in the VCR. There are arguments in favour [1] ISO 7816: Identification Cards, Parts 1–6.
(This ISO Standard describes “smart cards”).
of both approaches:
[2] ISO/IEC 13818-1: Generic coding of
In the existing IRD box moving pictures and associated audio
systems.
a) Having two complete descramblers in the IRD (This ISO/IEC Standard describes “MPEG-2”).
box, rather than one in the IRD box and one in [3] Common Interface Specification for
the video recorder, would reduce the cost and Conditional Access and other Digital Video
complexity of the overall system but only by a Broadcasting Decoder Applications.
relatively small amount; DVB Document A007, July 1995.
EBU Technical Review Winter 1995 77
EBU Project Group B/CA