This document provides an overview of a lecture on wireless communication systems. The lecture covers Wireless Local Area Networks (WLAN) standards such as 802.11b, 802.11a, and 802.11g. It also discusses emerging wireless technologies including Bluetooth, Ultra-Wideband (UWB), WiMax, and the fusion of telephony and IP networks. The lecture focuses in more detail on WiMax and Bluetooth standards, characteristics, architectures, and applications.
WIMAX stands for Worldwide Interoperability for Microwave Access.WiMAX refers to broadband wireless networks that are based on the IEEE 802.16 standard, which ensures compatibility and interoperability between broadband wireless access equipment.
The document discusses the evolution of wireless networks from 2G to 3G. It describes how 3G networks allow a broad range of wireless services to be provided efficiently through technologies like GPRS and EDGE that enhance data capabilities on existing networks. It also explains how completely new radio access technologies like UMTS using WCDMA can be used in new spectrum to optimize support for 3G services. Finally, it provides details on GPRS architecture and interfaces, describing how GPRS allows packet-switched data communications in GSM networks.
This document provides an overview of wireless personal area networks (WPANs), including Bluetooth, ZigBee, and Ultra-Wideband. It describes the key features and applications of each technology, how their protocols are structured, and how they compare to each other. Bluetooth supports data rates up to 2 Mbps over short ranges and is used in devices like phones, laptops, and printers. ZigBee focuses on low power consumption and supports thousands of nodes in a mesh network for uses like smart homes and buildings. Ultra-Wideband provides high data rates over short ranges and is used in applications like TVs, DVD players, and mobile devices.
This presentation describes about UMTS major components Key features, NodeB, RNC, GGSN,MSC, SGSN,VLR,HLR, Charging function, UMTS base stations and info about UMTS number allocated for MS.
Wi-Fi and WiMAX are wireless networking technologies. Wi-Fi uses radio waves to connect devices in local areas like homes and offices, while WiMAX can connect devices over longer distances of up to 30 miles, making it suitable for connecting entire cities. Both technologies transmit data using radio signals in specific frequency ranges and support various transmission speeds and encryption standards. Wi-Fi devices connect directly to a local wireless router or access point, while WiMAX uses wireless towers similar to cellular networks to connect multiple users over wider areas.
GSM is a 2G mobile communication system that provides voice and data services using radio frequency bands between 800-2000MHz. It has a three-part architecture including the radio subsystem with mobile stations, base stations and controllers; the network and switching subsystem with mobile switching centers and registers; and the operation subsystem for network management. Key protocols used in GSM include LAPDm for signaling, mobility management for registration and location updating, and call management for call establishment and control. GSM provides location tracking as users roam between different visitor location registers.
HiperLAN was developed as a wireless local area network standard by ETSI to provide higher data rates than early 802.11 standards. HiperLAN Type 1 achieved data rates up to 2 Mbps for ad hoc networking. HiperLAN Type 2 was later developed to provide connection-oriented service up to 54 Mbps, with quality of service guarantees, security, and flexibility. It uses OFDM in the 5 GHz spectrum for robust transmission. While early products only achieved 25 Mbps, the standard provides a framework for higher speeds as technologies advance. HiperLAN is intended to complement wired networks by providing wireless connectivity in hotspot areas like offices, homes, and public places.
WIMAX stands for Worldwide Interoperability for Microwave Access.WiMAX refers to broadband wireless networks that are based on the IEEE 802.16 standard, which ensures compatibility and interoperability between broadband wireless access equipment.
The document discusses the evolution of wireless networks from 2G to 3G. It describes how 3G networks allow a broad range of wireless services to be provided efficiently through technologies like GPRS and EDGE that enhance data capabilities on existing networks. It also explains how completely new radio access technologies like UMTS using WCDMA can be used in new spectrum to optimize support for 3G services. Finally, it provides details on GPRS architecture and interfaces, describing how GPRS allows packet-switched data communications in GSM networks.
This document provides an overview of wireless personal area networks (WPANs), including Bluetooth, ZigBee, and Ultra-Wideband. It describes the key features and applications of each technology, how their protocols are structured, and how they compare to each other. Bluetooth supports data rates up to 2 Mbps over short ranges and is used in devices like phones, laptops, and printers. ZigBee focuses on low power consumption and supports thousands of nodes in a mesh network for uses like smart homes and buildings. Ultra-Wideband provides high data rates over short ranges and is used in applications like TVs, DVD players, and mobile devices.
This presentation describes about UMTS major components Key features, NodeB, RNC, GGSN,MSC, SGSN,VLR,HLR, Charging function, UMTS base stations and info about UMTS number allocated for MS.
Wi-Fi and WiMAX are wireless networking technologies. Wi-Fi uses radio waves to connect devices in local areas like homes and offices, while WiMAX can connect devices over longer distances of up to 30 miles, making it suitable for connecting entire cities. Both technologies transmit data using radio signals in specific frequency ranges and support various transmission speeds and encryption standards. Wi-Fi devices connect directly to a local wireless router or access point, while WiMAX uses wireless towers similar to cellular networks to connect multiple users over wider areas.
GSM is a 2G mobile communication system that provides voice and data services using radio frequency bands between 800-2000MHz. It has a three-part architecture including the radio subsystem with mobile stations, base stations and controllers; the network and switching subsystem with mobile switching centers and registers; and the operation subsystem for network management. Key protocols used in GSM include LAPDm for signaling, mobility management for registration and location updating, and call management for call establishment and control. GSM provides location tracking as users roam between different visitor location registers.
HiperLAN was developed as a wireless local area network standard by ETSI to provide higher data rates than early 802.11 standards. HiperLAN Type 1 achieved data rates up to 2 Mbps for ad hoc networking. HiperLAN Type 2 was later developed to provide connection-oriented service up to 54 Mbps, with quality of service guarantees, security, and flexibility. It uses OFDM in the 5 GHz spectrum for robust transmission. While early products only achieved 25 Mbps, the standard provides a framework for higher speeds as technologies advance. HiperLAN is intended to complement wired networks by providing wireless connectivity in hotspot areas like offices, homes, and public places.
The document summarizes the key concepts from the course "Mobile Computing" taught in the sixth semester of the Bachelor of Engineering program in Computer Science and Engineering at RAMCO Institute of Technology. It covers the basics of mobile computing including definitions, applications, components of wireless communication systems, mobile communication architectures, and generations of mobile technologies from 1G to 5G. It also describes multiplexing techniques such as space division multiplexing, frequency division multiplexing, and time division multiplexing that allow multiple users to share communication channels and medium.
The document discusses several aspects of wireless local area networks (WLANs) including:
1. IEEE 802.11b is an enhancement of the original 802.11 standard that achieved data rates up to 11 Mbps using modifications to the physical layer.
2. IEEE 802.11a operates in the 5GHz band and supports data rates up to 54 Mbps using orthogonal frequency-division multiplexing (OFDM).
3. Many future developments are planned including enhancements to security, quality of service, and higher data rates above 100 Mbps.
This document summarizes several types of wireless networks. It discusses radio frequencies and frequency bands used in wireless communication. It then describes key aspects of cellular networks including UMTS, LTE, and their architectures. Wireless LANs are also covered, focusing on Wi-Fi standards, components like access points and controllers, and technologies such as MIMO. The document provides an overview of the fundamentals of various wireless networking technologies.
Ec8004 wireless networks unit 1 ieee 802.11a and ieee 802.11bHemalathaR31
IEEE 802.11b operates in the 2.4 GHz band with data rates from 1-11 Mbps and a transmission range of 300m outdoors and 30m indoors. It has wide manufacturer support and is inexpensive, making it suitable for home networks. Limitations include slow speeds, limited simultaneous users, and lack of scalability.
IEEE 802.11a operates in the 5 GHz band with higher data rates from 6-54 Mbps but shorter transmission ranges of 100m outdoors and 10m indoors. It uses OFDM modulation like BPSK, QPSK, 16-QAM and 64-QAM. It has faster speeds than 802.11b but shorter ranges.
This document provides an overview of mobile telecommunication systems including GSM, GPRS, and UMTS. It describes:
- The key components and architecture of GSM networks including the radio subsystem (mobile station and base station), networking and switching subsystem (MSC, HLR, VLR), and operation subsystem.
- The services provided by GSM like bearer services, teleservices, and supplementary services.
- Enhancements to GSM like GPRS which improved data transfer rates and UMTS which supported higher speech quality and data rates.
- How the transition from GSM to UMTS involved upgrades to network elements like the BTS, BSC, and addition of new
IEEE 802.11 is a set of media access control (MAC) and physical layer (PHY) specifications for implementing wireless local area network (WLAN) computer communication in the 2.4, 3.6, 5, and 60 GHz frequency bands. The goal of 802.11 is to provide simple, robust, and affordable wireless connectivity along with time-bound and asynchronous services. It uses either spread spectrum or infrared signaling techniques. The standard defines the MAC sublayer and three physical layer types: infrared, frequency-hopping spread spectrum (FHSS), and direct-sequence spread spectrum (DSSS). It supports infrastructure-based and ad-hoc network configurations.
This document discusses telecommunications and networking concepts. It covers topics like different communication methods within computer systems and between computers, various telecommunications media and devices, network layouts and protocols, how telecommunications has improved business operations, and recent developments in transmission speed. The document seeks to explain these telecommunications concepts and their importance for managers to understand in order to utilize telecommunications technologies effectively.
Here are the key points about guided and unguided transmission:
- Guided transmission uses physical media like wires and fiber optics to transmit signals along a directed path from transmitter to receiver. It allows for high-quality transmission but limits mobility.
- Unguided or wireless transmission converts signals to electromagnetic waves that can transmit through open space. It allows mobility as devices can communicate anywhere within range of a cell tower or access point. However, wireless signals can be interrupted by interference.
- Mobile communication involves transmission of data to/from handheld devices, with at least one being mobile. It uses wireless networks for mobility as users move around.
The document discusses wireless local area networks (WLANs) and the IEEE 802.11 standard. It introduces various WLAN standards including 802.11b operating at 11 Mbps in the 2.4 GHz band, 802.11a operating at up to 54 Mbps in the 5 GHz band, and 802.11g which also operates at up to 54 Mbps in the 2.4 GHz band. It describes the differences between infrastructure-based WLAN networks that use an access point and ad-hoc networks without an access point. It provides details on the IEEE 802.11 standard including the use of carrier sense multiple access with collision avoidance for medium access. It also discusses some enhancements to
This document discusses power consumption in telecommunication networks and strategies for reducing it. It begins by noting that telecommunication networks account for about 1/6 of the ICT sector's 2-4% share of global carbon emissions. It then examines the power usage of different network architectures including access networks, core networks, and customer premises equipment. The document analyzes the power consumption of specific technologies like DSL, optical fiber, WiMAX and LTE. It also provides methods for quantifying power usage and discusses various optimization strategies to reduce power consumption by switching off components, reducing network loads, and making technology improvements. These strategies aim to lower the environmental impact of telecommunication networks.
Here are the solutions to the examples:
Example 21.5:
Let f(x) = x^3 - 3x^2 + 2x. Then,
f'(x) = 3x^2 - 6x + 2.
Example 21.6:
Let f(x) = 5x - 3. Then,
f'(x) = 5.
Example 21.7:
Let f(x) = sqrt(x). Then,
f'(x) = 1/(2sqrt(x)).
This document summarizes several major mobile radio standards used in the United States and Europe. It provides information on the standard type, year introduced, multiple access technique used, operating frequency band, modulation type, and channel bandwidth for standards such as AMPS, GSM, CDMA, IS-95 and others. Additionally, it discusses the evolution of cellular networks through generations from analog to digital systems and increasing data capabilities.
UNIT III
MOBILE COMMUNICATION SYSTEMS
GSM-architecture-Location tracking and call setup- Mobility management- Handover-Security-GSM SMS –International roaming for GSM- call recording functions-subscriber and service data mgt –-Mobile Number portability -VoIP service for Mobile Networks –GPRS –Architecture-GPRS procedures-attach and detach procedures-PDP context procedure-combined RA/LA update procedures-Billing
This document provides an introduction to UMTS (Universal Mobile Telecommunications System). It describes the context and limitations of previous mobile systems that led to the development of 3G systems like UMTS. The goals of UMTS are to provide high-quality wireless multimedia services across converged fixed and mobile networks. The technical overview explains that UMTS uses CDMA to separate users within a cell and has both FDD and TDD duplex modes for frequency division.
This document discusses the origins and development of ad hoc networks. It describes how packet radio networks (PRNETs) in the 1970s, developed by DARPA, were the first generation of ad hoc networks. PRNETs used multi-hop routing between mobile radio terminals and packet radios to communicate without fixed infrastructure. The document outlines the key components and routing techniques of PRNETs, including point-to-point and broadcast routing. It also discusses how subsequent generations in the 1980s-1990s focused on improving performance, scalability, and developing commercial applications like Bluetooth.
EC8004 WIRELESS NETWORKS UNIT 5 - IMS HemalathaR31
This document provides an overview of the IMS (IP Multimedia Subsystem) architecture. IMS is a new architecture standardized by the telecommunications industry that allows for real-time and non-real-time multimedia sessions over an all-IP network. The key layers of the IMS architecture include the access layer, transport layer, session control layer, and application layer. The session control layer contains the main network control elements - the CSCF (Call Session Control Function) and HSS (Home Subscriber Server). The CSCF performs session routing and QoS management while the HSS stores user profiles.
UNIT II
WIRELESS NETWORKS
Wireless LAN – IEEE 802.11 Standards – Architecture – Services – Mobile Ad hoc Networks- WiFi and WiMAX - Wireless Local Loop
3G UMTS is a 3rd generation mobile network standard that aims to provide improved voice quality, higher data speeds, and more capacity compared to previous 2G standards. It utilizes W-CDMA technology along with a packet-switched core network to support data rates up to 2Mbps. Key aspects of 3G UMTS include soft handovers between base stations, advanced cellular planning to optimize coverage and capacity, and global roaming capabilities. While offering benefits over 2G, 3G also presented challenges such as high infrastructure costs and lack of adoption from some existing mobile users.
The document outlines LTE, 4G networks, and discusses technologies beyond 4G including 5G. It defines LTE and its key specifications. 4G is defined as supporting speeds up to 100Mbps for mobile and 1Gbps for stationary devices. Features of 4G networks include being fully IP-based, higher bandwidths, and support for new applications. Challenges in 4G include accessing different networks and managing terminal mobility across networks through location and handoff management. 5G is envisioned to provide even faster data rates and complete wireless communication with high performance.
WiMAX is a wireless technology that provides broadband connections over long distances. It uses towers to transmit high-speed Internet access to homes and businesses without wires. WiMAX operates using either line-of-sight or non-line-of-sight connections and can provide data rates between 30-40 megabits per second for mobile use and up to 1 gigabit per second for fixed locations. The WiMAX network is made up of towers, base stations, and an access service network that connects subscribers. It supports features like adaptive modulation, link-layer retransmissions, quality of service guarantees, and strong security.
WiMAX 2.0 is an update to the WiMAX standard that aims to provide higher data rates, lower latencies, and improved coverage compared to the original WiMAX 1.0 standard. It defines new physical and MAC layer specifications using OFDMA, supports carrier aggregation across multiple frequency bands, introduces advanced antenna techniques, and defines quality of service classes to efficiently allocate bandwidth. The document reviews the reasons for the WiMAX 2.0 update and key features such as increased data rates up to 1 Gbps, reduced framing overhead, support for heterogeneous networks, and enhanced interworking capabilities with other wireless technologies.
The document summarizes the key concepts from the course "Mobile Computing" taught in the sixth semester of the Bachelor of Engineering program in Computer Science and Engineering at RAMCO Institute of Technology. It covers the basics of mobile computing including definitions, applications, components of wireless communication systems, mobile communication architectures, and generations of mobile technologies from 1G to 5G. It also describes multiplexing techniques such as space division multiplexing, frequency division multiplexing, and time division multiplexing that allow multiple users to share communication channels and medium.
The document discusses several aspects of wireless local area networks (WLANs) including:
1. IEEE 802.11b is an enhancement of the original 802.11 standard that achieved data rates up to 11 Mbps using modifications to the physical layer.
2. IEEE 802.11a operates in the 5GHz band and supports data rates up to 54 Mbps using orthogonal frequency-division multiplexing (OFDM).
3. Many future developments are planned including enhancements to security, quality of service, and higher data rates above 100 Mbps.
This document summarizes several types of wireless networks. It discusses radio frequencies and frequency bands used in wireless communication. It then describes key aspects of cellular networks including UMTS, LTE, and their architectures. Wireless LANs are also covered, focusing on Wi-Fi standards, components like access points and controllers, and technologies such as MIMO. The document provides an overview of the fundamentals of various wireless networking technologies.
Ec8004 wireless networks unit 1 ieee 802.11a and ieee 802.11bHemalathaR31
IEEE 802.11b operates in the 2.4 GHz band with data rates from 1-11 Mbps and a transmission range of 300m outdoors and 30m indoors. It has wide manufacturer support and is inexpensive, making it suitable for home networks. Limitations include slow speeds, limited simultaneous users, and lack of scalability.
IEEE 802.11a operates in the 5 GHz band with higher data rates from 6-54 Mbps but shorter transmission ranges of 100m outdoors and 10m indoors. It uses OFDM modulation like BPSK, QPSK, 16-QAM and 64-QAM. It has faster speeds than 802.11b but shorter ranges.
This document provides an overview of mobile telecommunication systems including GSM, GPRS, and UMTS. It describes:
- The key components and architecture of GSM networks including the radio subsystem (mobile station and base station), networking and switching subsystem (MSC, HLR, VLR), and operation subsystem.
- The services provided by GSM like bearer services, teleservices, and supplementary services.
- Enhancements to GSM like GPRS which improved data transfer rates and UMTS which supported higher speech quality and data rates.
- How the transition from GSM to UMTS involved upgrades to network elements like the BTS, BSC, and addition of new
IEEE 802.11 is a set of media access control (MAC) and physical layer (PHY) specifications for implementing wireless local area network (WLAN) computer communication in the 2.4, 3.6, 5, and 60 GHz frequency bands. The goal of 802.11 is to provide simple, robust, and affordable wireless connectivity along with time-bound and asynchronous services. It uses either spread spectrum or infrared signaling techniques. The standard defines the MAC sublayer and three physical layer types: infrared, frequency-hopping spread spectrum (FHSS), and direct-sequence spread spectrum (DSSS). It supports infrastructure-based and ad-hoc network configurations.
This document discusses telecommunications and networking concepts. It covers topics like different communication methods within computer systems and between computers, various telecommunications media and devices, network layouts and protocols, how telecommunications has improved business operations, and recent developments in transmission speed. The document seeks to explain these telecommunications concepts and their importance for managers to understand in order to utilize telecommunications technologies effectively.
Here are the key points about guided and unguided transmission:
- Guided transmission uses physical media like wires and fiber optics to transmit signals along a directed path from transmitter to receiver. It allows for high-quality transmission but limits mobility.
- Unguided or wireless transmission converts signals to electromagnetic waves that can transmit through open space. It allows mobility as devices can communicate anywhere within range of a cell tower or access point. However, wireless signals can be interrupted by interference.
- Mobile communication involves transmission of data to/from handheld devices, with at least one being mobile. It uses wireless networks for mobility as users move around.
The document discusses wireless local area networks (WLANs) and the IEEE 802.11 standard. It introduces various WLAN standards including 802.11b operating at 11 Mbps in the 2.4 GHz band, 802.11a operating at up to 54 Mbps in the 5 GHz band, and 802.11g which also operates at up to 54 Mbps in the 2.4 GHz band. It describes the differences between infrastructure-based WLAN networks that use an access point and ad-hoc networks without an access point. It provides details on the IEEE 802.11 standard including the use of carrier sense multiple access with collision avoidance for medium access. It also discusses some enhancements to
This document discusses power consumption in telecommunication networks and strategies for reducing it. It begins by noting that telecommunication networks account for about 1/6 of the ICT sector's 2-4% share of global carbon emissions. It then examines the power usage of different network architectures including access networks, core networks, and customer premises equipment. The document analyzes the power consumption of specific technologies like DSL, optical fiber, WiMAX and LTE. It also provides methods for quantifying power usage and discusses various optimization strategies to reduce power consumption by switching off components, reducing network loads, and making technology improvements. These strategies aim to lower the environmental impact of telecommunication networks.
Here are the solutions to the examples:
Example 21.5:
Let f(x) = x^3 - 3x^2 + 2x. Then,
f'(x) = 3x^2 - 6x + 2.
Example 21.6:
Let f(x) = 5x - 3. Then,
f'(x) = 5.
Example 21.7:
Let f(x) = sqrt(x). Then,
f'(x) = 1/(2sqrt(x)).
This document summarizes several major mobile radio standards used in the United States and Europe. It provides information on the standard type, year introduced, multiple access technique used, operating frequency band, modulation type, and channel bandwidth for standards such as AMPS, GSM, CDMA, IS-95 and others. Additionally, it discusses the evolution of cellular networks through generations from analog to digital systems and increasing data capabilities.
UNIT III
MOBILE COMMUNICATION SYSTEMS
GSM-architecture-Location tracking and call setup- Mobility management- Handover-Security-GSM SMS –International roaming for GSM- call recording functions-subscriber and service data mgt –-Mobile Number portability -VoIP service for Mobile Networks –GPRS –Architecture-GPRS procedures-attach and detach procedures-PDP context procedure-combined RA/LA update procedures-Billing
This document provides an introduction to UMTS (Universal Mobile Telecommunications System). It describes the context and limitations of previous mobile systems that led to the development of 3G systems like UMTS. The goals of UMTS are to provide high-quality wireless multimedia services across converged fixed and mobile networks. The technical overview explains that UMTS uses CDMA to separate users within a cell and has both FDD and TDD duplex modes for frequency division.
This document discusses the origins and development of ad hoc networks. It describes how packet radio networks (PRNETs) in the 1970s, developed by DARPA, were the first generation of ad hoc networks. PRNETs used multi-hop routing between mobile radio terminals and packet radios to communicate without fixed infrastructure. The document outlines the key components and routing techniques of PRNETs, including point-to-point and broadcast routing. It also discusses how subsequent generations in the 1980s-1990s focused on improving performance, scalability, and developing commercial applications like Bluetooth.
EC8004 WIRELESS NETWORKS UNIT 5 - IMS HemalathaR31
This document provides an overview of the IMS (IP Multimedia Subsystem) architecture. IMS is a new architecture standardized by the telecommunications industry that allows for real-time and non-real-time multimedia sessions over an all-IP network. The key layers of the IMS architecture include the access layer, transport layer, session control layer, and application layer. The session control layer contains the main network control elements - the CSCF (Call Session Control Function) and HSS (Home Subscriber Server). The CSCF performs session routing and QoS management while the HSS stores user profiles.
UNIT II
WIRELESS NETWORKS
Wireless LAN – IEEE 802.11 Standards – Architecture – Services – Mobile Ad hoc Networks- WiFi and WiMAX - Wireless Local Loop
3G UMTS is a 3rd generation mobile network standard that aims to provide improved voice quality, higher data speeds, and more capacity compared to previous 2G standards. It utilizes W-CDMA technology along with a packet-switched core network to support data rates up to 2Mbps. Key aspects of 3G UMTS include soft handovers between base stations, advanced cellular planning to optimize coverage and capacity, and global roaming capabilities. While offering benefits over 2G, 3G also presented challenges such as high infrastructure costs and lack of adoption from some existing mobile users.
The document outlines LTE, 4G networks, and discusses technologies beyond 4G including 5G. It defines LTE and its key specifications. 4G is defined as supporting speeds up to 100Mbps for mobile and 1Gbps for stationary devices. Features of 4G networks include being fully IP-based, higher bandwidths, and support for new applications. Challenges in 4G include accessing different networks and managing terminal mobility across networks through location and handoff management. 5G is envisioned to provide even faster data rates and complete wireless communication with high performance.
WiMAX is a wireless technology that provides broadband connections over long distances. It uses towers to transmit high-speed Internet access to homes and businesses without wires. WiMAX operates using either line-of-sight or non-line-of-sight connections and can provide data rates between 30-40 megabits per second for mobile use and up to 1 gigabit per second for fixed locations. The WiMAX network is made up of towers, base stations, and an access service network that connects subscribers. It supports features like adaptive modulation, link-layer retransmissions, quality of service guarantees, and strong security.
WiMAX 2.0 is an update to the WiMAX standard that aims to provide higher data rates, lower latencies, and improved coverage compared to the original WiMAX 1.0 standard. It defines new physical and MAC layer specifications using OFDMA, supports carrier aggregation across multiple frequency bands, introduces advanced antenna techniques, and defines quality of service classes to efficiently allocate bandwidth. The document reviews the reasons for the WiMAX 2.0 update and key features such as increased data rates up to 1 Gbps, reduced framing overhead, support for heterogeneous networks, and enhanced interworking capabilities with other wireless technologies.
WIMAN , wireless communication technology JadduKota
This document summarizes a technical seminar presentation on WiMAX technology. WiMAX stands for Worldwide Interoperability for Microwave Access and provides broadband wireless connectivity over long distances at speeds comparable to Wi-Fi but over a larger range like 3G services. The presentation discusses the IEEE 802.16 standards, features of WiMAX like OFDM modulation and encryption, types of WiMAX connections, how a WiMAX network is structured with base stations and receivers, differences between WiMAX and Wi-Fi, challenges in implementing WiMAX like signal decay over distance, and problems WiMAX needs to address like providing high-speed mobile access.
The document discusses 4G mobile communications standards including WiMAX and LTE. It provides information on:
- IEEE 802.22 which uses white spaces in TV frequencies for wireless regional area networks.
- Requirements for 4G standards defined by ITU including peak speeds of 1Gbps.
- How early versions of Mobile WiMAX and LTE did not meet the full 4G requirements but were still branded as 4G.
- Mobile WiMAX Release 2 and LTE Advanced promising speeds of 1Gbps in 2013.
The document discusses 4G mobile communications technologies WiMAX and LTE. It provides an overview of the IEEE 802.22 standard for wireless regional area networks using vacant TV channels. It also discusses the history and development of 4G standards, requirements for IMT-Advanced 4G, and early commercial versions of Mobile WiMAX and LTE that provided speeds less than 1 Gbit/s. It compares key aspects of 3G and 4G mobile networks.
The document discusses the objectives, components, use cases, and research directions of CSIR's 5G testbed. The objectives are to provide thought leadership in 5G development, build human capital, drive innovation through demonstrations, contribute to standards and policy, contextualize technologies for local use cases, and position the country for the fourth industrial revolution. The testbed implements 5G network slicing, NB-IoT for IoT communications, a core network functionality benchmarking tool, and explores areas like multi-slice support, edge computing, dedicated networks, and industrial communication reliability. Key focus areas for research are autonomous networks, software-defined networking, edge computing, low latency networks, smart agriculture, security, and more.
WiMAX is a wireless technology that provides broadband internet access over long distances. It uses radio waves to transmit data and can provide connectivity up to 30 miles from a base station. WiMAX uses the IEEE 802.16 standard and consists of components like the base station, receiver, and antennas. It establishes connections like cellular networks but provides faster speeds than WiFi for connecting larger areas.
These slides explain the Protocol Framework for 5G mmWave Backhaul Network, as a part of a project presentation for the course Telecom Architecture at Northeastern University.
Objective is to include the brief insight on 5G network architecture and standard progress, Accumulated it from different paper/journal, vendor’s white paper and different blog.
3G networks faced issues accommodating mobile internet demand, including high costs of expanding networks. Performance was also low in densely populated and dead spot areas. IMT-Advanced networks were developed to address these issues by providing higher data rates, better mobility support, improved indoor coverage, and more compatible international roaming compared to 3G networks. WiMAX is a telecommunications technology that can provide wireless broadband internet over wide areas as an alternative to DSL and cable. It uses the IEEE 802.16 standard and can transmit data at distances of up to 30 miles.
This document summarizes the history and key standards of wireless internet communication. It discusses the major milestones including the original 802.11 standard from 1997 and subsequent amendments that increased bandwidth and functionality. It describes the technologies used by each standard such as DSSS and OFDM. The document also discusses wireless LAN applications and challenges, as well as the Wireless Application Protocol (WAP) which aimed to make internet content accessible on mobile phones.
The document discusses wireless LAN (WLAN) and wireless metropolitan area network (WMAN) technologies. It provides an overview of the IEEE 802.11 and 802.16 standards for WLANs and WMANs respectively, outlining the goals and evolution of the standards over time to support higher data rates and new frequencies of operation. It also discusses wireless personal area network (WPAN) technologies including Bluetooth and how they differ from WLANs in terms of power levels, coverage areas, and supported devices.
This document provides an overview of cellular network technologies from 1G to 4G. It summarizes the evolution from analog 1G networks to digital 2G networks, then to 2.5G and 3G networks with increased data capabilities. 4G networks are described as providing further increased throughput through advanced technologies like OFDMA. Key multiple access technologies like FDMA, TDMA, CDMA used in different generations are explained. Popular cellular standards GSM and CDMA are discussed in detail along with their network architecture and capabilities. The transition from 2G to 2.5G to 3G using technologies like GPRS, EDGE is outlined. The goals and applications of 4G networks are described as fully converged services on a range
GSM, CDMA, and WiMax are wireless communication standards. GSM is a 2G standard used by mobile phones that operates in frequency bands between 850-1900 MHz. CDMA is a multiple access technique that allows several transmitters to send information simultaneously over a single channel. WiMax is a wireless broadband standard that provides data rates up to 1 Gbit/s for fixed stations and portable mobile broadband connectivity across cities. It provides alternatives to cable and DSL for last mile broadband access.
This document provides an overview of wireless networks and the IEEE 802.11 standards. It discusses wireless LAN technologies including IEEE 802.11, HiperLAN, Bluetooth, and various amendments. It describes the infrastructure and ad-hoc modes of wireless LANs. It also summarizes key standards such as 802.11a, 802.11b, their architectures, protocols, and parameters. Finally, it provides details on the HiperLAN standard developed by ETSI for wireless local area networks in Europe.
WiMAX technology allows for wireless broadband connectivity over long distances in a more economical way than other wireless technologies. It works by using towers to transmit high-speed network signals up to 30 miles to both fixed and mobile receivers. Key benefits include serving many users at once from a single tower, faster deployment than wired networks, large coverage areas, standardization allowing interoperability between equipment, and providing high-speed broadband access at lower costs than other options. However, it also has drawbacks like needing line-of-sight for long-distance connections, susceptibility to weather interference, and high installation costs for equipment.
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WiMAX (Worldwide Interoperability for Microwave Access) is a wireless industry coalition dedicated to the advancement of IEEE 802.16 standards for broadband wireless access (BWA) networks.
Wireless communication systems provide mobility and connectivity anywhere through high data rates, quality of service, and extended ranges of up to 50km. WiMAX is a wireless technology that can deliver broadband access through fixed and mobile networks in an economical way. It transforms mobile broadband by supporting up to 75Mbps for devices like laptops. Key capabilities include centralized coordination, high-speed IP services, quality of service, and compatibility between equipment. WiMAX uses OFDM to optimize delivery of services and enables applications like voice, video, and Internet access over wide metropolitan areas.
Data Transmission Analysis using MW-5000 at 5.8 GHz Frequency IJECEIAES
This document summarizes an experiment on data transmission analysis using a MW-5000 module at 5.8 GHz frequency. The experiment found that the duration for data transmission depends on the length of the message and the baud rate setting. Testing various message lengths at a fixed baud rate of 4800 resulted in similar transmission durations. However, transmitting the same message at different baud rates showed that higher baud rates reduced the transmission duration. Specifically, a message sent at 4800 baud took 1.14 seconds while at 9600 baud it took 0.60 seconds. The document concludes that transmission duration is influenced by message length and baud rate.
The document proposes changes to address SMS fraud by describing the use of a TCAP handshake for mobile terminated SMS transfers. Specifically, it:
1) Describes using a TCAP handshake prior to the MAP payload exchange to provide a limited level of message authenticity without using MAPsec.
2) Proposes measures for networks to take to counteract spoofing attempts, such as verifying the SMS-GMSC address matches the originating SCCP address.
3) Suggests a method for operators to gradually introduce the TCAP handshake by defining trusted and untrusted operator groups with different requirements.
The study found that 69.2% of 195 young Iraq and Afghanistan veterans visiting a VA PTSD clinic were at high risk for sleep apnea. The risk of sleep apnea increased with the severity of PTSD symptoms, with every clinically significant increase in PTSD symptoms associated with a 40% increase in risk of sleep apnea. Screening for sleep apnea is important for veterans with PTSD since untreated sleep apnea can lead to health issues and exacerbate PTSD symptoms. The relationship between sleep apnea and PTSD in veterans remains unclear but may involve disturbed sleep and hyperarousal from combat or chronic stress from PTSD.
This document provides a summary of recent research on PTSD and related topics. It lists over 30 research articles and reports published in January 2016 covering a wide range of topics including PTSD treatment outcomes, the effects of combat deployment on mental health providers, the impact of stress and social support on military children, the diagnostic criteria of PTSD, masculinity and community reintegration in veterans with traumatic brain injury, and relationships between mental health issues like depression, substance abuse and suicide in military populations.
WiMAX is an emerging wireless broadband technology that provides transmission of data over long distances. The WiMAX Forum aims to ensure interoperability between WiMAX products based on the 802.16 wireless network standards. While no WiMAX compliant products currently exist, they are expected in 2005 and will be based on the 802.16d standard. WiMAX allows for both fixed and mobile broadband connections using various spectrum bands and modulation techniques to provide transmission ranges from 1-50 km depending on conditions.
This document describes a bit-serial message-passing low-density parity-check (LDPC) decoder. It discusses the history and use of channel coding and different coding techniques. It then explains the structure and min-sum decoding algorithm for LDPC codes. The document proposes a bit-serial message passing technique for the decoder architecture to reduce routing congestion compared to fully parallel architectures. It provides implementation details of an application-specific integrated circuit (ASIC) and field-programmable gate array (FPGA) version of the decoder.
This document provides an overview of a lecture on wireless communication systems. The lecture covers Wireless Local Area Networks (WLAN) standards such as 802.11b, 802.11a, and 802.11g. It also discusses emerging wireless technologies including Bluetooth, Ultra-Wideband (UWB), WiMax, and the fusion of telephony and IP networks. The lecture focuses in more detail on WiMax and Bluetooth standards, characteristics, architectures, and applications.
The document discusses the architecture of WiMAX networks, including:
- The generic mobile WiMAX architectural model includes an access network, core network, and application service providers with flexible relationships between network operators.
- There are three defined ASN profiles - Profile A with separate BS and ASN-GW, Profile B with combined BS and ASN-GW, and Profile C similar to Profile A but with RRM functions in the BS.
- Key network features discussed include AAA and roaming frameworks, QoS framework, and mobility framework based on mobile IP or proxy mobile IP.
- Interworking with 3G networks is also described, including common billing scenarios and using a WiMAX CSN I
WiMAX is a wireless technology that provides broadband internet access over long distances. It can offer speeds up to 1 Gbit/s for fixed access and 40 Mbit/s for mobile access. WiMAX was developed to provide wireless alternatives to cable and DSL through standards developed by the IEEE and promoted by the WiMAX Forum. It has applications for broadband internet, mobile backhaul, and triple-play services. Users connect to WiMAX networks using gateways, USB dongles, or some mobile phones.
This document provides an overview of ASN.1 (Abstract Syntax Notation One) and encoding rules. ASN.1 defines the syntax for messages exchanged between applications independently of machine representation. Encoding rules like BER (Basic Encoding Rules) and PER (Packed Encoding Rules) define how ASN.1 messages are encoded for transmission. ASN.1 sees widespread use for applications like audio/video streaming, electronic commerce, telephony, and network management. It provides benefits like language/platform independence and reduced development time.
This document provides a summary of the contents of a report on mobile prepay communications. The report is divided into four parts that cover: 1) technical introduction and issues, 2) marketing and business issues, 3) advanced concepts and applications, and 4) deployment and operational issues. It discusses topics like the technology behind prepay, target markets, commercial offerings, marketing strategies, payment options, and future trends in prepay. The author's goal is to provide knowledge on technical and business issues related to prepay strategy, planning, deployment and operations.
This document provides a tutorial on multi-core CPUs, computer clusters, and grid computing for economists. It begins by discussing trends in microprocessor development such as increasing transistor counts and clock speeds. Future improvements will come from multi-core CPUs rather than increased clock speed. It also discusses increases in network speeds that enable computer clusters and grids. The document then provides suggestions for optimizing code performance on a single CPU before parallelization. This includes minimizing branches, inlining subroutines, and using high-performance libraries. The rest of the document discusses programming multi-core CPUs, clusters, and grids.
Miami in touch-amdocs-lte-2011-05-16-handoutArthur Sanchez
Vodafone Germany implemented an Amdocs OSS solution for their LTE deployments to accelerate processes for LTE planning and rollout. The Amdocs solution provided automated inventory, provisioning, and maintenance capabilities for LTE equipment. This improved planner efficiency and reduced TCO. Initial results showed accelerated ROI through an early milestone and improved collaboration between teams. Lessons learned included having an onsite Amdocs presence, securing management attention, and balancing design documentation with flexibility.
Frost & sullivan oss-bss global competitive strategiesArthur Sanchez
This document summarizes a report on next generation tools for network planning and engineering. It discusses how network planning has expanded beyond physical infrastructure to include capacity planning and logical service design. It also outlines business requirements for these tools like accelerating the design process, reducing errors, improving network survivability, and better supporting field personnel. Several vendor case studies are also reviewed that aim to meet these new requirements through integrated solutions.
Alpha lipoic acid (ALA) is a metabolic antioxidant that aids in energy production and reduces oxidative stress. It helps treat diabetes by improving insulin sensitivity and reducing neuropathy symptoms. ALA also enhances the effects of other antioxidants like vitamins C and E. It may help manage blood sugar levels and has potential benefits for skin health, detoxification, and types of glaucoma.
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.
Your One-Stop Shop for Python Success: Top 10 US Python Development Providersakankshawande
Simplify your search for a reliable Python development partner! This list presents the top 10 trusted US providers offering comprehensive Python development services, ensuring your project's success from conception to completion.
How to Interpret Trends in the Kalyan Rajdhani Mix Chart.pdfChart Kalyan
A Mix Chart displays historical data of numbers in a graphical or tabular form. The Kalyan Rajdhani Mix Chart specifically shows the results of a sequence of numbers over different periods.
Digital Marketing Trends in 2024 | Guide for Staying AheadWask
https://www.wask.co/ebooks/digital-marketing-trends-in-2024
Feeling lost in the digital marketing whirlwind of 2024? Technology is changing, consumer habits are evolving, and staying ahead of the curve feels like a never-ending pursuit. This e-book is your compass. Dive into actionable insights to handle the complexities of modern marketing. From hyper-personalization to the power of user-generated content, learn how to build long-term relationships with your audience and unlock the secrets to success in the ever-shifting digital landscape.
zkStudyClub - LatticeFold: A Lattice-based Folding Scheme and its Application...Alex Pruden
Folding is a recent technique for building efficient recursive SNARKs. Several elegant folding protocols have been proposed, such as Nova, Supernova, Hypernova, Protostar, and others. However, all of them rely on an additively homomorphic commitment scheme based on discrete log, and are therefore not post-quantum secure. In this work we present LatticeFold, the first lattice-based folding protocol based on the Module SIS problem. This folding protocol naturally leads to an efficient recursive lattice-based SNARK and an efficient PCD scheme. LatticeFold supports folding low-degree relations, such as R1CS, as well as high-degree relations, such as CCS. The key challenge is to construct a secure folding protocol that works with the Ajtai commitment scheme. The difficulty, is ensuring that extracted witnesses are low norm through many rounds of folding. We present a novel technique using the sumcheck protocol to ensure that extracted witnesses are always low norm no matter how many rounds of folding are used. Our evaluation of the final proof system suggests that it is as performant as Hypernova, while providing post-quantum security.
Paper Link: https://eprint.iacr.org/2024/257
Ivanti’s Patch Tuesday breakdown goes beyond patching your applications and brings you the intelligence and guidance needed to prioritize where to focus your attention first. Catch early analysis on our Ivanti blog, then join industry expert Chris Goettl for the Patch Tuesday Webinar Event. There we’ll do a deep dive into each of the bulletins and give guidance on the risks associated with the newly-identified vulnerabilities.
Skybuffer AI: Advanced Conversational and Generative AI Solution on SAP Busin...Tatiana Kojar
Skybuffer AI, built on the robust SAP Business Technology Platform (SAP BTP), is the latest and most advanced version of our AI development, reaffirming our commitment to delivering top-tier AI solutions. Skybuffer AI harnesses all the innovative capabilities of the SAP BTP in the AI domain, from Conversational AI to cutting-edge Generative AI and Retrieval-Augmented Generation (RAG). It also helps SAP customers safeguard their investments into SAP Conversational AI and ensure a seamless, one-click transition to SAP Business AI.
With Skybuffer AI, various AI models can be integrated into a single communication channel such as Microsoft Teams. This integration empowers business users with insights drawn from SAP backend systems, enterprise documents, and the expansive knowledge of Generative AI. And the best part of it is that it is all managed through our intuitive no-code Action Server interface, requiring no extensive coding knowledge and making the advanced AI accessible to more users.
Trusted Execution Environment for Decentralized Process MiningLucaBarbaro3
Presentation of the paper "Trusted Execution Environment for Decentralized Process Mining" given during the CAiSE 2024 Conference in Cyprus on June 7, 2024.
Skybuffer SAM4U tool for SAP license adoptionTatiana Kojar
Manage and optimize your license adoption and consumption with SAM4U, an SAP free customer software asset management tool.
SAM4U, an SAP complimentary software asset management tool for customers, delivers a detailed and well-structured overview of license inventory and usage with a user-friendly interface. We offer a hosted, cost-effective, and performance-optimized SAM4U setup in the Skybuffer Cloud environment. You retain ownership of the system and data, while we manage the ABAP 7.58 infrastructure, ensuring fixed Total Cost of Ownership (TCO) and exceptional services through the SAP Fiori interface.
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.
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
An English 🇬🇧 translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/temporal-event-neural-networks-a-more-efficient-alternative-to-the-transformer-a-presentation-from-brainchip/
Chris Jones, Director of Product Management at BrainChip , presents the “Temporal Event Neural Networks: A More Efficient Alternative to the Transformer” tutorial at the May 2024 Embedded Vision Summit.
The expansion of AI services necessitates enhanced computational capabilities on edge devices. Temporal Event Neural Networks (TENNs), developed by BrainChip, represent a novel and highly efficient state-space network. TENNs demonstrate exceptional proficiency in handling multi-dimensional streaming data, facilitating advancements in object detection, action recognition, speech enhancement and language model/sequence generation. Through the utilization of polynomial-based continuous convolutions, TENNs streamline models, expedite training processes and significantly diminish memory requirements, achieving notable reductions of up to 50x in parameters and 5,000x in energy consumption compared to prevailing methodologies like transformers.
Integration with BrainChip’s Akida neuromorphic hardware IP further enhances TENNs’ capabilities, enabling the realization of highly capable, portable and passively cooled edge devices. This presentation delves into the technical innovations underlying TENNs, presents real-world benchmarks, and elucidates how this cutting-edge approach is positioned to revolutionize edge AI across diverse applications.
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
2. 2 | 57
Communication Systems
Last lecture – UMTS, WCDMA, Wireless LAN
●
Last session devoted to telephony networks and UMTS
encoding – WCDMA on the air interface
− WCDMA uses Code Division Multiplexing instead of Time
Division Multiplexing and Frequency Division Multiplexing
− Per participant a binary channalization code is used
thus multiple signals on just one frequency
●
Switched over then to other mobile technologies,
especially Wireless LAN
− Standardization of Wireless LAN technology started
in1997 the IEEE approved 802.11
− The standard specifies the MAC and the physical layers
for transmissions in the 2.4 GHz band
3. 3 | 57
Communication Systems
Last lecture – Wireless LAN standards
●
Later on the first really popular standard IEEE 802.11b was
created, which works at additional signal rates of 5.5 and 11
Mbit/s.
●
By the end of the 90s, the IEEE approved the specifications
of 802.11a, which uses the 5 GHz band, allowing brutto signal
rates of 6, 9, 12, 18, 24, 36, 48 up to 54 Mbit/s
●
In 2003, the IEEE approved 802.11g as a further evolution of
the 802.11 standard, providing the same performance as
802.11a, while working in the 2.4 GHz band. Compatible with
802.11b devices
− most modern devices are equipped with g standard
adaptors by now
− wireless technology becomes increasingly popular
by now
4. 4 | 57
Communication Systems
This lecture – Wireless LAN and wireless technologies
●
Thus we will find more mobile solutions for data
communication than GSM, UMTS and WLAN
●
There are several reasons for the evolution of new
wireless standards
− not all requirements could be met with GSM, UMTS or
WLAN
− the data rates of GSM are rather small compared to
todays multimedia content and demands of modern
networked applications, delay is an important issue for
real time applications and communication
− UMTS covers greater areas, but costs are rather high and
bandwidth is medium compared to WLAN technology
− on the other side GSM and UMTS offer a well established
framework for user administration, accounting and billing
on a really world wide scale
5. 5 | 57
Communication Systems
This lecture – Wireless LAN and wireless technologies
●
WLANs of the most widely used b and g (a/h) standards
on the other side offer rather high bandwidth and short
delay, but often
− suboptimal regarding power consumption
− layer 2 security
− every-where access
− user-authentication
− bandwidth compared to classical Ethernet infrastructure
●
Therefore we have additional concepts tackling some of
the issues mentioned above
− Bluetooth for low-power, short-range, low-bandwidth
communication
6. 6 | 57
Communication Systems
This lecture – More on wireless technologies
●
Bluetooth is widely established and accepted in small
mobile devices like mobile phones, PDAs, headsets, ...
to replace wiring
●
UWB – Ultra Wide Band as an upcoming high bandwidth
technology which should be able to share bandwidth
with other users and is authorized to operate in the
range of 3.1 upto 16GHz
●
“Wireless DSL” - different wide area network
technologies in the former band of old analogous
mobile phone networks to cover rural areas and offer
high speed Internet access in sparsely populated areas
●
WiMaX as a new wireless standard for MANs
●
WiMaX and Bluetooth are covered in this lecture
7. 7 | 57
Communication Systems
This lecture – Network fusion
●
UWB is a rather new technology and not many products
are available by now, but you will find some articles on
it in the net
●
In the second part of lecture we will switch over again
and talk on fusion of telephony and IP networks
8. 8 | 57
Communication Systems
WiMAX - Worldwide Interoperability for Microwave Access
●
Broadband Wireless MAN Standard
●
Defines wireless service that provide a communications path between
a subscriber site and a core network such as the public telephone
network and the Internet.
●
"a standards-based technology enabling the delivery of last mile
wireless broadband access as an alternative to cable and DSL."
●
Standards:
−
IEEE Std 802.16-2004: addresses fixed and portable systems.
−
Amendment 802.16e: Adds mobility components to the standard,
called “Mobile WiMAX”.
●
WiMAX Forum coordinates interoperability testing -- “WiMAX Forum
Certified”.
9. 9 | 57
Communication Systems
WiMAX- characteristics
●
Frequency ranges 10-66 GHz and 2-11 GHz.
●
Broad bandwidth: Up to 134 Mbit/s in 28 MHz channel (10-66 GHz air
interface)
●
Accommodate either TDD or FDD.
●
Supports higher layer or transport protocols such as ATM, Ethernet or IP.
●
MAC is designed for very high bit rates (up to 268 mbps each way), while
delivering ATM compatible Quality of Service.
●
Frame structure allows terminals to be dynamically assigned uplink and
downlink burst profiles according to their link conditions.
●
MAC uses variable length PDU and other concepts to increase efficiency.
●
MAC uses a self-correcting bandwidth request/grant scheme that
eliminates the overhead and delay of acknowledgements, while
simultaneously allowing better QoS handling.
●
High security: supports AES and 3DES.
●
IEEE 802.16e allows full mobility at speeds up to 160 km/hr.
12. 12 | 57
Communication Systems
WiMAX – architecture and application
●
WiMAX system consists of two parts
●
WiMAX Base station (tower): can cover up to 10 km radius
●
WiMAX Subscriber station (receiver): sits in your laptop or
computer.
●
Several base stations are connected with one another by high-speed
backhaul microwave links, allowing for roaming by a WiMAX
subscriber from one base station to another base station area.
●
WiMAX has two main topologies
●
Point to Point for backhaul
●
Point to Multi-Point Base station for Subscriber station
●
Typical areas of application of WiMAX
●
Residential and SOHO High Speed Internet Access.
●
Small and Medium Business.
●
WiFi Hot Spot Backhaul
13. 13 | 57
Communication Systems
WiMAX – wireless services
●
Line-of-sight
−
A fixed dish antenna points straight at the WiMAX tower from a
rooftop or pole.
−
11 GHz to 66 GHz frequency range
−
At higher frequencies - there is less interference and lots more
bandwidth
−
The connection is stronger and more stable, so it is able to send
a lot of data with fewer errors.
●
Non-line-of-sight
−
A small antenna on your computer connects to the WiMAX tower
−
2 GHz to 11 GHz frequency range
−
At lower frequencies – longer wavelength transmissions are not
as easily disrupted by physical obstructions – they are better able
to diffract, or bend, around obstacles
15. 15 | 57
Communication Systems
WiMAX – reference model
●
Service-Specific Convergence Sublayer (CS):
−
provides transformation or mapping of external network data, received
through the CS service access point (SAP), into MAC SDUs received by
the MAC Common Part Sublayer (CPS) through the MAC SAP.
●
MAC Common Part Sublayer (MAC CPS):
−
provides the core MAC functionality of system access, bandwidth
allocation, connection establishment, and connection maintenance.
−
receives data from the various CSs, through the MAC SAP, classified to
particular MAC connections.
−
Data, PHY control, and statistics are transferred between the MAC CPS
and the PHY via the PHY SAP.
●
A seperate security sublayer provides authentication, secure key exchange,
and encryption.
●
Physical Layer (PHY) includes multiple specification, each appropriate to a
particular frequency range and application.
17. 17 | 57
●
Bluetooth is a radio standard and communications protocol
primarily designed for low power consumption, with a short
range (power class dependent: 1 meter, 10 meters, 100
meters) based around low-cost transceiver microchips in
each device
●
Intended to replace the cable(s) connecting portable and/or
fixed electronic devices
●
Designed to operate in noisy frequency environments, the
Bluetooth radio uses a fast acknowledgement and frequency
hopping scheme to make the link robust
●
Bluetooth radio modules operate in the unlicensed ISM band
at 2.4GHz, use frequency hopping and change freq. every
42 times a millisecond, hop is synchronized by cell master
Communication Systems
Bluetooth technology - introduction
18. 18 | 57
●
Compared with other systems in the same frequency band,
the Bluetooth radio hops faster and uses shorter packets
●
Currently at version 1.2.
●
Since March 2002, an IEEE standard, namely IEEE 802.15.1.
●
Unlicensed 2.4GHz radio band, ISM (industrial,
scientific,medical) band - available worldwide, also used by
Microwave ovens, 802.11, HomeRF…
●
Gross data rate of 1 Mbit/s
●
Basic 10m range extended to 100m with amplifiers
Communication Systems
Bluetooth - characteristics
19. 19 | 57
●
TDMA - TDD - Frequency hopping
●
Mixed voice / data paths
●
Encryption, low power, low cost
●
Extremely small
●
Ubiquitous radio link
●
Bluetooth technology offers built-in simple networking on layer
2
−
thus it attracted the academic world to do research on dynamic
networks basing on scattered, moving, emerging and
disappearing mobile devices
●
A Bluetooth device may operate in master mode or in slave
mode
Communication Systems
Bluetooth - characteristics
20. 20 | 57
●
A maximum of 8 devices (7 active slaves plus 1 master) form a
Piconet
●
A piconet is characterized by the master: frequency hopping
scheme, access code, timing synchronization, bit rate allocated
to each slave
●
Only one master: dynamically selected, roles can be switched
●
Up to 7 active slaves; up to 255 parked slaves
●
No central network structure: “Ad-hoc” network
Communication Systems
Bluetooth network topology - Piconet
21. 21 | 57
●
Interconnected piconets, one master per piconet
●
A few devices shared between piconets
●
No central network structure: “Ad-hoc” network
Communication Systems
Bluetooth network topology -Scatternet
23. 23 | 57
●
Radio layer: defines the requirements for a Bluetooth
transceiver operating in the 2.4 GHz ISM band
●
Baseband layer: describes the specification of the Bluetooth
Link Controller (LC) which carries out the baseband protocols
and other low-level link routines
●
Link Manager Protocol (LMP): is used by the Link Managers
(on either side) for link set-up and control
●
Host Controller Interface (HCI): provides a command interface
to the Baseband Link Controller and Link Manager, and access
to hardware status and control registers
●
Logical Link Control and Adaptation Protocol (L2CAP):
supports higher level protocol multiplexing, packet
segmentation and reassembly, and the conveying of quality of
service information
Communication Systems
Bluetooth protocol stack
24. 24 | 57
●
RFCOMM protocol: provides emulation of serial ports over the
L2CAP protocol. The protocol is based on the ETSI standard
TS 07.10
●
Service Discovery Protocol (SDP): provides a means for
applications to discover which services are provided or
available
●
For experimenting the Linux BT stack (www.bluez.org) might
be a good start
−
it is a really good implementation of the standard and supports
the various Bluetooth profiles offered by the different devices
−
it is OpenSource and provides the necessary programming
libraries
Communication Systems
Bluetooth protocol stack
25. 25 | 57
Communication Systems
Bluetooth profiles and dependencies
●
A profile can
be described
as a vertical
slice through
the protocol
stack
●
A profile has
dependencie
s on the
profiles in
which it is
contained
directly and
indirectly
26. 26 | 57
●
Bluetooth Profiles were written to make sure
that the application level works the same way
across different manufacturers' products
●
Bluetooth applications:
−
Wireless control of and communication between
a cell phone and a hands free headset or car kit.
−
Wireless networking between PCs in a confined
space and where little bandwidth is required
−
Wireless communications with PC input devices
such as mice and keyboards
−
Wireless communications to PC output devices
such as printers
Communication Systems
Bluetooth - applications
27. 27 | 57
−
Wireless communications with PC input
devices such as mice and keyboards.
−
Wireless communications to PC output
devices such as printers
−
Transfer of files between devices via OBEX
−
Replacement of traditional wired serial
communications in test equipment, GPS
receivers and medical equipment
−
Thus often a serial interface is emulated
over the BT link as shown on the following
slides ...
−
Remote controls where infrared was
traditionally used
−
...
Communication Systems
Bluetooth - applications
28. 28 | 57
●
Often Bluetooth is the best way to link devices like mobile
phones to a laptop
mobile linux # hcitool scan
Scanning ...
00:0E:07:47:93:1B T610
mobile linux # hcitool cc 00:0E:07:47:93:1B
mobile linux # hcitool dc 00:0E:07:47:93:1B
●
Scan for Bluetooth devices within the range of the BT adaptor
−
this is much more fun to do on specific fairs like the Cebit,
where you can compile a list of more then 20 devices within
range
−
if your are lucky some of the devices use broken firmware and
security could be overridden – with special tools you can access
the mobile device, get the phone books, alter entries and so
on ...
●
hcitool is just a helper to connect, authenticate, disconnect, ...
to/from a device
Communication Systems
Bluetooth in Linux OS – an example for the rfcomm layer
29. 29 | 57
●
hciconfig - show the Bluetooth device and its properties
mobile linux # hciconfig
hci0: Type: PCCARD
BD Address: 00:04:76:C8:4A:E8 ACL MTU: 128:8 SCO MTU: 64:8
UP RUNNING PSCAN ISCAN AUTH ENCRYPT
RX bytes:1046 acl:0 sco:0 events:58 errors:0
TX bytes:850 acl:0 sco:0 commands:35 errors:0
mobile linux # hcitool dev
Devices:
hci0 00:04:76:C8:4A:E8
mobile linux # l2ping 00:0E:07:47:93:1B
Ping: 00:0E:07:47:93:1B from 00:04:76:C8:4A:E8 (data size 20) ...
0 bytes from 00:0E:07:47:93:1B id 200 time 63.05ms
0 bytes from 00:0E:07:47:93:1B id 201 time 48.13ms
0 bytes from 00:0E:07:47:93:1B id 202 time 45.13ms
3 sent, 3 received, 0% loss
●
l2ping is a layer 2 ping utility to check connection on a specific
linked device
●
as you can see, the average trip time is much higher than e.g. in
WLAN
Communication Systems
Bluetooth in Linux OS – an example for the rfcomm layer
30. 30 | 57
●
In next step the emulated serial link could be started
mobile linux # rfcomm connect 1 00:0E:07:47:93:1B 1
Connected /dev/rfcomm1 to 00:0E:07:47:93:1B on channel 1
Press CTRL-C for hangup
mobile linux # pppd call gprs-o2wap
Press CTRL-C to close the connection at any stage!
defining PDP context...
rATZ
OK
AT&F
OK
ATV1E0S0=0&D2&C1
OK
●
Which is just used as the lower layer protocol for a PPP connection
part between the computer and device
●
The mobile phone “translates” the data stream for the WAN GSM
interface, GPRS protocol as explained in earlier lecture
●
Of course there are more options for BT protocols between the two
devices, like OBEX for file transfer (e.g. stored MP3, ...)
Communication Systems
Bluetooth in Linux OS
31. 31 | 57
●
Bluetooth is oriented to connecting close devices, serving as a
substitute for cables
●
Wi-Fi is oriented towards computer-to-computer connections, as an
extension of or substitution for cable LANs.
●
802.11b and Blutooth both utilize the free 2.4GHz band
●
no exclusive use
●
no guarantees
●
special protocol implementations needed to cope with noise, fading, ...
●
Bluetooth uses frequency hopping and changes freq. every 42
times a millisecond, hop is synchronized by cell master
●
802.11a/h WLAN standards use the free 5Ghz band
●
band is reserved for WLAN only
●
range is more restricted than with 802.11b
●
bandwidth is increased up to 54Mbit
Communication Systems
Bluetooth v. Wi-Fi
34. 34 | 43
Communication Systems
network technologies and network fusion
●
By now we have presented a certain range of
communication networks and their underlying
technologies
●
The “early” (means standards dating from the 70s and
80s) digital wired and wireless networks were focused
on the transportation of voice
●
The developers of the first drafts on internet protocols
had data communication in mind when defining their
standards
●
The processes of standardization were really different
− closed clubs of telephony providers and equipment
manufacturers backed up by their states and a rather open
process in the definition of internet protocols and applications
− but by now both worlds learn of each other and closing the
gaps in between ...
35. 35 | 43
Communication Systems
network fusion
●
For a rather long time telephone and data networks
were different entities – remember the network
taxonomy
− packet orientated vs. circuit switched
− packet orientation is rather efficient in bandwidth using but
cannot give any guarantees on packet delivery
− bandwidth growth and optional QoS helped to offer service
quality near to circuit switching
●
Why to provide two completely different infrastructures for
rather the same services?
− voice is just another piece of data (and not the biggest one
compared to other applications and services in use)
36. 36 | 43
Communication Systems
real time communication
●
traditional telephony networks are circuit switching
networks
− rather centrally operated
− setup of connection inband or out of band before
communication starts
− no routing delays in transmit
− reserved bandwidth for every connection
− rather homogeneous transport media
●
more and more real time services are handled over the
Internet, but
− hop-by-hop routing without clear hierarchy
− different media and bandwidth
37. 37 | 43
Communication Systems
real time communication
●
Voice-over-IP (VoIP) is a big hype at the moment
− every network equipment vendor has some products in its
portfolio (even companies like Siemens are able to offer
products conforming to standards!!)
− many new “telephone companies” evolve to offer services, the
old providers have to think on new strategies
− all of them hope for reduction of costs and a source for roaring
profits :-)
●
so TCP/IP is just used for another application/service
38. 38 | 43
Communication Systems
delay in communication
●
This service has to meet some requirements
●
Important issue in communication – delay and packet loss
(infinite delay)
●
Many applications heavily depend on near no delay (e.g.
real time communication, like VoIP, Video and multi-
user online gaming ... :-) )
●
Routing delay
− High setup delay in virtual circuit networks – no delay if
path is set up (imagine telephone network)
− No setup delay in datagram networks, but routing
decision for every packet in every router
39. 39 | 43
Communication Systems
delay in communication
●
Other types of delay
− Transmission, nodal processing, queuing, propagation
delay
●
Transmission delay (example given with message
segmentation)
− Is L/R (L size of packet in bit, R rate in bit/s)
− e.g. Packet of 1500Byte (standard MTU – max. transfer
unit in ethernets) on 100MBits LAN travels 0,000015s
(=15µs) to be transferred completely
40. 40 | 43
Communication Systems
delay in communication
●
Ping between two hosts connected via 100Mbits ethernet
− Linux-OS, between 550MHz PII/Cel and P4/2,4GHz,
100Mbits interface cards
41. 41 | 43
Communication Systems
delay in communication
●
Processing delay is time for
− Evaluating header information
− Check for bit errors
− Decision on outgoing route
●
Should be in order of microseconds in high speed routers
and servers
●
Queuing delay – in packet switching networks overbooking
of resources may occur (no bandwidth reservation as with
VC)
− Packets have to wait (a certain time) until sent out
42. 42 | 43
Communication Systems
delay in packet switched networks
●
Propagation of signal in physical medium may add to delay
too
− Normally in order of nanoseconds in LAN and milliseconds in
WAN
− We cannot do much on it – but we get some problems:
●
Imagine 300km WAN optical link of 10GBit/s (e.g. in GEANT)
●
300km/300.000km/s=0.001s (1ms)
●
10GBit/s*0.001s = 0.01GBit = 10MBit “on wire” (signal sent
out but not received by destination)
●
=> rising “capacity of wire” with rising speed
− Important problem in cluster and parallel computing (!) - you
need extremely fast connections on very short distances
43. 43 | 43
Communication Systems
delay in packet switched networks
●
Propagation and transmission delays are different
− Propagation is the travel time of one signal (single bit)
− Transmission measures time for transferring one packet
(independent on distance, but dependent on bandwidth and
packet size)
●
Processing delay is sum of delays mentioned above
dnodal
= dtrans
+ dproc
+ dqueue
+ dprop
● Contribution of every delay to dnodal
may vary heavily
44. 44 | 43
Communication Systems
delay in packet switched networks
● The delay of packets in the output queue dqueue
is most important
− Depends on the traffic intensity
− Even when average traffic rate is lower than bandwidth long
queues may build up with very bursty traffic
− First packet is sent out directly all following can suffer
increasing delay
− Standard problem on routers with different uplink bandwidth
●
If outgoing queue is full packets are dropped
●
Packet losses increase with traffic intensity
45. 45 | 43
Communication Systems
delay in packet switched networks
●
End system to end system delay is sum of all nodal delays along
the path from source to destination
●
Helper program to get an idea on path and delay is traceroute
(exercises in practical course, see mtr too)
46. 46 | 55
●
Voice over IP and Quality of Service:
− Major challenges: delay and delay variation (jitter)
− Delay jitter is the variability of source-to-destination delays of
packets within the same packet stream
− Voice applications are usually interactive
− delay requirement for a telephone system: 150ms-250ms
●
We identified some of the sources of delay in a voice over IP
system:
− OS delay: 10s-100s milliseconds (digitisazion of data,
compression and inter software data handling) ...
●
Special multimedia protocol is introduced next lecture ...
Internet Working
requirements towards network
47. 47 | 57
Bluetooth v. Wi-Fi
− http://dienst.isti.cnr.it/Dienst/Repository/2.0/Body/ercim.cnr.isti/2004-TR-
27/pdf?tiposearch=cnr&langver=
− http://en.wikipedia.org/wiki/Bluetooth
WiMAX
− 802.16: http://standards.ieee.org/getieee802/download/802.16-
2004.pdf
− IEEE 802.16a:
http://www.wimaxforum.org/news/downloads/WiMAXWhitepaper.pd
f
− Telephoy's complete guide to WiMAX:
http://www.wimaxforum.org/news/press_releases/Telephony_WiMAX.pdf
− http://computer.howstuffworks.com/wimax1.htm
− http://searchnetworking.techtarget.com/searchNetworking/downloads/Finneran.pd
f
− Can WiMAX address your application:
http://www.wimaxforum.org/news/downloads/Can_WiMAX_Address_You
r_Applications_final.pdf
− http://www.wimaxforum.org/technolog
Communication Systems
End/Literature