This document provides an overview of the network layer and IP addressing. It discusses:
1) The functions and position of the network layer based on the OSI and TCP/IP models. The key duty is interconnecting different networks and making them appear as a single network.
2) Duties of the network layer including uniquely addressing devices, packetizing data, routing packets between networks, and fragmentation. IP is the primary network layer protocol.
3) IP addressing including the concepts of unicast, multicast, and classful addressing schemes. It also covers converting between binary and dotted-decimal notation for IP addresses.
Packaging and distributing python code to PypiMicroPyramid .
This document summarizes how to package and distribute Python modules. It discusses using PyPI and PIP to install packages, the folder structure and files needed for a package, and how to register and upload a package to PyPI so it can be downloaded by others. Key steps include creating a setup.py file, generating distribution files with Python setup.py, and using Twine to upload the files to PyPI.
This document discusses and compares single page applications (SPAs) and multi-page applications (MPAs). It notes that SPAs load faster, run faster, and work offline as only the content is loaded via AJAX/JSON while the main page remains the same. Popular SPA frameworks mentioned include AngularJS, ReactJS, ExtJS, KnockoutJS, and EmberJS. While SPAs provide advantages for speed, development, and debugging, disadvantages include issues with search engine optimization, back button functionality, and testing. The document emphasizes that neither approach is a one-size-fits-all solution and developers should decide what best fits their needs based on considering advantages and disadvantages. It also stresses the importance of
Syllable is a free and open source operating system for Pentium and compatible processors. Its purpose is to create an easy-to-use desktop operating system for home and small office users. Syllable Desktop is optimized for personal computers with a graphical user interface, while Syllable Server is optimized for server computers and based on the Linux kernel. Both systems aim to be easy to use while retaining power and flexibility.
This document discusses audio and video support in HTML5. It covers the audio and video elements that allow embedding multimedia content in web pages without requiring plugins. The audio element is used to embed audio files while the video element embeds video files. Both support various attributes to control playback like autoplay, controls, and loop. Common audio and video file formats like MP3, MP4, Ogg and WebM are supported in HTML5. The document provides examples of using the audio and video elements and describes their attributes.
The document discusses the benefits of exercise for both physical and mental health. Regular exercise can improve cardiovascular health, reduce stress and anxiety, boost mood, and enhance cognitive function. Staying physically active for at least 30 minutes each day is recommended for significant health benefits.
This document discusses CSS text formatting properties including text color, alignment, decoration, transformation, indentation, letter spacing, and line height. It provides examples of how each property can be used by specifying the property name and value in a CSS style rule. For example, to center align text the text-align property is set to center. Various text formatting properties allow control over text color, positioning, effects, spacing, and other visual aspects through CSS.
EyeOS is an open-source cloud operating system that allows users to access applications and files through a web browser from any internet-connected device, without needing to be installed locally. It functions similarly to a traditional desktop OS but resides entirely on the web. EyeOS has been in development since 2005 and is written primarily in PHP, XML, and JavaScript, with security measures like firewalls and daily backups. It provides a platform for easily creating new web applications and is useful for situations requiring portability and centralized storage like education and remote work.
Packaging and distributing python code to PypiMicroPyramid .
This document summarizes how to package and distribute Python modules. It discusses using PyPI and PIP to install packages, the folder structure and files needed for a package, and how to register and upload a package to PyPI so it can be downloaded by others. Key steps include creating a setup.py file, generating distribution files with Python setup.py, and using Twine to upload the files to PyPI.
This document discusses and compares single page applications (SPAs) and multi-page applications (MPAs). It notes that SPAs load faster, run faster, and work offline as only the content is loaded via AJAX/JSON while the main page remains the same. Popular SPA frameworks mentioned include AngularJS, ReactJS, ExtJS, KnockoutJS, and EmberJS. While SPAs provide advantages for speed, development, and debugging, disadvantages include issues with search engine optimization, back button functionality, and testing. The document emphasizes that neither approach is a one-size-fits-all solution and developers should decide what best fits their needs based on considering advantages and disadvantages. It also stresses the importance of
Syllable is a free and open source operating system for Pentium and compatible processors. Its purpose is to create an easy-to-use desktop operating system for home and small office users. Syllable Desktop is optimized for personal computers with a graphical user interface, while Syllable Server is optimized for server computers and based on the Linux kernel. Both systems aim to be easy to use while retaining power and flexibility.
This document discusses audio and video support in HTML5. It covers the audio and video elements that allow embedding multimedia content in web pages without requiring plugins. The audio element is used to embed audio files while the video element embeds video files. Both support various attributes to control playback like autoplay, controls, and loop. Common audio and video file formats like MP3, MP4, Ogg and WebM are supported in HTML5. The document provides examples of using the audio and video elements and describes their attributes.
The document discusses the benefits of exercise for both physical and mental health. Regular exercise can improve cardiovascular health, reduce stress and anxiety, boost mood, and enhance cognitive function. Staying physically active for at least 30 minutes each day is recommended for significant health benefits.
This document discusses CSS text formatting properties including text color, alignment, decoration, transformation, indentation, letter spacing, and line height. It provides examples of how each property can be used by specifying the property name and value in a CSS style rule. For example, to center align text the text-align property is set to center. Various text formatting properties allow control over text color, positioning, effects, spacing, and other visual aspects through CSS.
EyeOS is an open-source cloud operating system that allows users to access applications and files through a web browser from any internet-connected device, without needing to be installed locally. It functions similarly to a traditional desktop OS but resides entirely on the web. EyeOS has been in development since 2005 and is written primarily in PHP, XML, and JavaScript, with security measures like firewalls and daily backups. It provides a platform for easily creating new web applications and is useful for situations requiring portability and centralized storage like education and remote work.
CSS is used to style and lay out web pages. It allows separation of document content from page layout and design. CSS declarations are made up of selectors and properties. Selectors identify elements on the page and properties set specific styles for those elements, like color, font, size, and layout. CSS rules cascade based on specificity and source, with more specific and inline rules taking precedence over broader and external rules. Inheritance passes down text-based styles by default.
HAProxy TCP 모드에서 클라이언트의 Source IP를 내부 서버로 전달하는 방법을 알아봅니다.
* 중간에 오타가 있어서 수정본을 다시 업로드 하고자 했으나... SlideShare 측의 답변으로는 "Re-Upload 기능을 제거했다."라고 합니다. 부디 오타 등 부자연스러운 부분에 대해 너그럽게 이해를 부탁 드립니다.
20160331_Automate the boring stuff with pythonSungman Jang
The document is a book in Korean titled "Automate the Boring Stuff with Python" that teaches Python programming. It has two main parts: Part 1 covers Python basics like flow control, functions, lists, and strings. Part 2 covers automating tasks with Python like working with files, web scraping, Excel, PDFs, and controlling the keyboard and mouse. The book compares Python to other languages like Java and C++, explaining why Python is a productive language for automation tasks.
The document provides an overview of installing PHP on Windows systems. It discusses choosing between the Windows InstallShield method (for beginners) or manual binary installation. The InstallShield process is demonstrated step-by-step using IIS as an example, covering downloading, choosing options, file extensions, and testing. The manual method requires copying files, setting permissions, and configuring the web server by adding application mappings in IIS. Examples demonstrate including header and footer files to create templates.
This document discusses configuring AWS CodeBuild projects to access resources within a VPC. It provides an example CodeBuild project configuration that specifies the VPC ID, subnet IDs, and security group IDs to enable VPC access. It also includes examples of buildspec.yml files used by CodeBuild projects, one for a Java project and one for packaging a CloudFormation template.
This document provides an introduction and overview of web programming. It discusses the history and architecture of the web, including how HTML, CSS, and JavaScript are used on the client-side and server-side. It covers the basic structure of HTML documents and how to add common elements like text, links, images and lists. It also introduces CSS for styling HTML elements with selectors, properties and positioning. Finally, it demonstrates some popular development tools and libraries like jQuery, Kendo UI, and ExtJS that can be used to build user interfaces.
Your website has out-of-control CSS bloat. You know your performance is being impacted, but how do you move from organic CSS with no particular architecture to something lighter, more logical, and easier to maintain? In this session, Nicole Sullivan and Stoyan Stefanov will show you how they improved the CSS at Facebook and Yahoo! Search. After this session you will know how to:
1. Use lint tools to automate and evaluate the efficiency of your CSS
2. Avoid the top 5 causes of CSS bloat, and
3. Speed up your site by making the UI code an order of magnitude smaller.
How to shutdown and power up of the netapp cluster mode storage systemSaroj Sahu
This slide will guide you how to shutdown and power up of the Netapp cluster mode storage system in command mode. (It will depict you environmental shutdown process (SAN environment in a DataCenter)
NicheTech is providing Wordpress training in Ahmedabad.
We are providing best wordpress training in Ahmedabad.
WWW.Facebook.com/liveprojecttrainingAhmedabad
This document provides a 3-step tutorial for beginners to set up a PHP development environment on their local machine and write simple PHP scripts. Step 1 explains how to install a local server like WAMP. Step 2 demonstrates a "Hello World" PHP script and how to test it. Step 3 introduces PHP variables and shows a simple example of echoing a variable.
A detailed comparison of two commonly used PowerDNS Authoritative Server Web GUIs, geared mostly towards teams and projects recently introduced to PowerDNS.
The document discusses several HTML tags for embedding multimedia content. It describes the <audio> and <video> tags for including sound and video files respectively. It notes the supported file formats for each. It also covers the <iframe> tag for embedding another HTML document inline. It details the attributes of the <iframe> tag and compares it to the deprecated <frame> tag, noting that <iframe> embeds content within the current document while <frame> broke the document paradigm.
Storage as a Service provides scalable cloud storage through APIs that abstract the underlying implementation. OpenStack is an open source cloud platform that includes Cinder for block storage and Swift for object storage. Cinder provides persistent block storage volumes that can be attached to instances, while Swift stores scalable objects accessible through APIs.
This document summarizes a webinar about importing crime data from Chicago into Neo4j. It discusses loading a CSV file of crime data into Neo4j using LOAD CSV and creating nodes and relationships. It also describes using Spark to preprocess the CSV into multiple Neo4j-formatted files and bulk loading them using the Neo4j Import tool. The document then covers enriching the graph with additional crime data from JSON and updating the graph with new crimes.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
The document demonstrates different methods for specifying colors in CSS including RGBA, HSL, HSLA, and opacity. RGBA colors are assigned to paragraphs with red, green and blue backgrounds. HSL colors use hue, saturation and lightness values to create a green color at different intensities. HSLA extends HSL by adding opacity. Opacity is directly applied to RGB colors to create semi-transparent red, green and blue backgrounds.
The document discusses the key steps involved in setting up a website, including acquiring a domain name, choosing a web hosting provider, uploading files to the web server, and making the site accessible online. It covers topics like common web server operating systems, the differences between shared and dedicated hosting, and using an FTP client like FileZilla to transfer files from a local computer to the hosting server.
A presentation from 4/8/09 for my graduate Industrial Training class at University of Memphis. Covers the basics of Wordpress, installation, plugins, themes, and video.
This document provides an overview of the Python programming language. It begins by explaining what Python is - a general purpose, interpreted programming language that can be used as both a programming and scripting language. It then discusses the differences between programs and scripting languages. The history and creator of Python, Guido van Rossum, are outlined. The document explores the scope of Python and what tasks it can be used for. Popular companies and industries that use Python today are listed. Reasons why people use Python, such as it being free, powerful, and portable, are provided. Instructions for installing Python and running Python code are included. The document covers Python code execution and introduces basic Python concepts like variables, strings, data types, lists
The document discusses network layer protocols and IP addressing. It covers the functions of the network layer including routing, logical addressing, internetworking, and fragmentation. It then describes IP addressing, including address space, notations like binary, dotted decimal, and hexadecimal. It explains classful addressing and how addresses are divided into network ID and host ID for classes A, B, and C. Class A uses 8-bit network IDs and 24-bit host IDs, class B uses 16-bit network IDs and 16-bit host IDs, and class C uses 24-bit network IDs and 8-bit host IDs. Rules for assigning network IDs and host IDs are also provided.
Unit 1- Network Layer and Protocols-4.pptxDESTROYER39
The document discusses an advanced computer network subject code. It provides details on the examination scheme, syllabus units, and content for the network layer including IP addressing, protocols, datagram format, routing, and addressing mechanisms. Key topics covered are IP addressing notation, classful and classless addressing, network and transport layer protocols, and duties of the network layer for routing and packet transmission.
CSS is used to style and lay out web pages. It allows separation of document content from page layout and design. CSS declarations are made up of selectors and properties. Selectors identify elements on the page and properties set specific styles for those elements, like color, font, size, and layout. CSS rules cascade based on specificity and source, with more specific and inline rules taking precedence over broader and external rules. Inheritance passes down text-based styles by default.
HAProxy TCP 모드에서 클라이언트의 Source IP를 내부 서버로 전달하는 방법을 알아봅니다.
* 중간에 오타가 있어서 수정본을 다시 업로드 하고자 했으나... SlideShare 측의 답변으로는 "Re-Upload 기능을 제거했다."라고 합니다. 부디 오타 등 부자연스러운 부분에 대해 너그럽게 이해를 부탁 드립니다.
20160331_Automate the boring stuff with pythonSungman Jang
The document is a book in Korean titled "Automate the Boring Stuff with Python" that teaches Python programming. It has two main parts: Part 1 covers Python basics like flow control, functions, lists, and strings. Part 2 covers automating tasks with Python like working with files, web scraping, Excel, PDFs, and controlling the keyboard and mouse. The book compares Python to other languages like Java and C++, explaining why Python is a productive language for automation tasks.
The document provides an overview of installing PHP on Windows systems. It discusses choosing between the Windows InstallShield method (for beginners) or manual binary installation. The InstallShield process is demonstrated step-by-step using IIS as an example, covering downloading, choosing options, file extensions, and testing. The manual method requires copying files, setting permissions, and configuring the web server by adding application mappings in IIS. Examples demonstrate including header and footer files to create templates.
This document discusses configuring AWS CodeBuild projects to access resources within a VPC. It provides an example CodeBuild project configuration that specifies the VPC ID, subnet IDs, and security group IDs to enable VPC access. It also includes examples of buildspec.yml files used by CodeBuild projects, one for a Java project and one for packaging a CloudFormation template.
This document provides an introduction and overview of web programming. It discusses the history and architecture of the web, including how HTML, CSS, and JavaScript are used on the client-side and server-side. It covers the basic structure of HTML documents and how to add common elements like text, links, images and lists. It also introduces CSS for styling HTML elements with selectors, properties and positioning. Finally, it demonstrates some popular development tools and libraries like jQuery, Kendo UI, and ExtJS that can be used to build user interfaces.
Your website has out-of-control CSS bloat. You know your performance is being impacted, but how do you move from organic CSS with no particular architecture to something lighter, more logical, and easier to maintain? In this session, Nicole Sullivan and Stoyan Stefanov will show you how they improved the CSS at Facebook and Yahoo! Search. After this session you will know how to:
1. Use lint tools to automate and evaluate the efficiency of your CSS
2. Avoid the top 5 causes of CSS bloat, and
3. Speed up your site by making the UI code an order of magnitude smaller.
How to shutdown and power up of the netapp cluster mode storage systemSaroj Sahu
This slide will guide you how to shutdown and power up of the Netapp cluster mode storage system in command mode. (It will depict you environmental shutdown process (SAN environment in a DataCenter)
NicheTech is providing Wordpress training in Ahmedabad.
We are providing best wordpress training in Ahmedabad.
WWW.Facebook.com/liveprojecttrainingAhmedabad
This document provides a 3-step tutorial for beginners to set up a PHP development environment on their local machine and write simple PHP scripts. Step 1 explains how to install a local server like WAMP. Step 2 demonstrates a "Hello World" PHP script and how to test it. Step 3 introduces PHP variables and shows a simple example of echoing a variable.
A detailed comparison of two commonly used PowerDNS Authoritative Server Web GUIs, geared mostly towards teams and projects recently introduced to PowerDNS.
The document discusses several HTML tags for embedding multimedia content. It describes the <audio> and <video> tags for including sound and video files respectively. It notes the supported file formats for each. It also covers the <iframe> tag for embedding another HTML document inline. It details the attributes of the <iframe> tag and compares it to the deprecated <frame> tag, noting that <iframe> embeds content within the current document while <frame> broke the document paradigm.
Storage as a Service provides scalable cloud storage through APIs that abstract the underlying implementation. OpenStack is an open source cloud platform that includes Cinder for block storage and Swift for object storage. Cinder provides persistent block storage volumes that can be attached to instances, while Swift stores scalable objects accessible through APIs.
This document summarizes a webinar about importing crime data from Chicago into Neo4j. It discusses loading a CSV file of crime data into Neo4j using LOAD CSV and creating nodes and relationships. It also describes using Spark to preprocess the CSV into multiple Neo4j-formatted files and bulk loading them using the Neo4j Import tool. The document then covers enriching the graph with additional crime data from JSON and updating the graph with new crimes.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
The document demonstrates different methods for specifying colors in CSS including RGBA, HSL, HSLA, and opacity. RGBA colors are assigned to paragraphs with red, green and blue backgrounds. HSL colors use hue, saturation and lightness values to create a green color at different intensities. HSLA extends HSL by adding opacity. Opacity is directly applied to RGB colors to create semi-transparent red, green and blue backgrounds.
The document discusses the key steps involved in setting up a website, including acquiring a domain name, choosing a web hosting provider, uploading files to the web server, and making the site accessible online. It covers topics like common web server operating systems, the differences between shared and dedicated hosting, and using an FTP client like FileZilla to transfer files from a local computer to the hosting server.
A presentation from 4/8/09 for my graduate Industrial Training class at University of Memphis. Covers the basics of Wordpress, installation, plugins, themes, and video.
This document provides an overview of the Python programming language. It begins by explaining what Python is - a general purpose, interpreted programming language that can be used as both a programming and scripting language. It then discusses the differences between programs and scripting languages. The history and creator of Python, Guido van Rossum, are outlined. The document explores the scope of Python and what tasks it can be used for. Popular companies and industries that use Python today are listed. Reasons why people use Python, such as it being free, powerful, and portable, are provided. Instructions for installing Python and running Python code are included. The document covers Python code execution and introduces basic Python concepts like variables, strings, data types, lists
The document discusses network layer protocols and IP addressing. It covers the functions of the network layer including routing, logical addressing, internetworking, and fragmentation. It then describes IP addressing, including address space, notations like binary, dotted decimal, and hexadecimal. It explains classful addressing and how addresses are divided into network ID and host ID for classes A, B, and C. Class A uses 8-bit network IDs and 24-bit host IDs, class B uses 16-bit network IDs and 16-bit host IDs, and class C uses 24-bit network IDs and 8-bit host IDs. Rules for assigning network IDs and host IDs are also provided.
Unit 1- Network Layer and Protocols-4.pptxDESTROYER39
The document discusses an advanced computer network subject code. It provides details on the examination scheme, syllabus units, and content for the network layer including IP addressing, protocols, datagram format, routing, and addressing mechanisms. Key topics covered are IP addressing notation, classful and classless addressing, network and transport layer protocols, and duties of the network layer for routing and packet transmission.
IP and MAC addresses are unique identifiers for devices connected to a network or the internet.
An IP address identifies a device and allows information to be sent between devices, while a MAC address specifically identifies the device's network interface card. IP addresses contain both a network ID and host ID to identify the network segment and individual device. There are two main versions of IP - IPv4 uses 32-bit addresses and IPv6 uses 128-bit addresses. IP addresses are classified into five categories - Classes A, B, C, D and E - which determine how many bits are used for the network vs host portions.
The document discusses internetworking and how to build an internet from the ground up. It describes how different networking technologies are interconnected through protocols like TCP/IP which allow communication across heterogeneous networks by smoothing out differences. Layered models and protocols are explained, including how packets are routed from one network to another through gateways and fragmented if needed to traverse networks with different maximum transmission units.
The document discusses TCP/IP configuration and addressing. It describes:
1) The layers of the TCP/IP model including the application, transport, internet, and link layers.
2) IP addressing including public vs private addresses, IPv4 and IPv6 address formats, classes of IPv4 addresses including class A, B, C, and private addresses.
3) Networking concepts related to addressing like subnetting, supernetting, VLSM, and IPv6 addressing formats including colon hexadecimal and compressed formats.
The document discusses the Internet Protocol (IP) which is the cornerstone of the TCP/IP architecture and allows all computers on the Internet to communicate. There are two main versions of IP - IPv4, the currently used version, and IPv6 which is intended to replace IPv4 and includes improvements like longer addresses. IP addresses are 32-bit for IPv4 and 128-bit for IPv6. Strategies like private addressing and Classless Inter-Domain Routing (CIDR) help conserve the limited number of available IP addresses.
This document discusses the Internet Protocol (IP) version 4 and 6. It describes the key tasks of IP including addressing computers and fragmenting packets. IP version 4 uses 32-bit addresses while IP version 6 uses 128-bit addresses and has improvements like larger address space and better security. The document also covers IP address classes, private addressing, subnetting, Classless Inter-Domain Routing (CIDR), and address blocks.
1. The document discusses IP addressing and routing. It introduces the concepts of hierarchical addressing using IP addresses and subnets to make routing scalable in large internets.
2. Subnetting allows a single IP network number to be divided into multiple physical networks or "subnets". Each subnet is assigned a subnet number and subnet mask to identify the portion of the IP address used for the subnet.
3. Routers use subnet masks and forwarding tables containing subnet numbers, masks, and next hops to route packets between subnets and networks. This hierarchical addressing scheme reduces the routing information needed compared to using individual host addresses.
TCP/IP is a set of communication protocols developed in the 1970s to connect dissimilar networks. It includes the two main protocols TCP and IP. TCP functions at the transport layer to provide reliable data transmission through connections. IP functions at the network layer to route packets by addressing each device with a unique IP address. TCP/IP is commonly used today and supports communication over the internet through protocols like HTTP, FTP, and SMTP.
The document provides an introduction to IP addressing and subnetting. Some key points include:
- An IP address identifies a device on an IP network and is made up of 32 binary bits divided into a network and host portion using a subnet mask.
- IP addresses are written in dotted decimal format with four octets separated by periods.
- IP addresses allow devices to communicate using TCP/IP by sending and receiving IP packets.
- IP addresses are classified into classes A, B, and C depending on the range of the first octet. Each class supports a different number of networks and hosts.
- Subnetting allows a network to be divided into multiple subnets while appearing as a single network externally using a subnet
1. Serial0 is up but the line protocol is down, indicating a potential issue with the cable or configuration settings not matching on both ends.
2. Static IP addresses are manually assigned while dynamic IP addresses are assigned by a DHCP server from its IP range, and have a lease duration after which the address may change.
3. Protocols establish rules and standards for moving data across a network, such as routing protocols like RIP, IGRP, and EIGRP that determine the best path between networks.
1. A host creates a packet and places the destination address in the header.
2. The host sends the packet to the nearest router.
3. Each router uses the destination address to select the next router and forwards the packet.
4. The packet is forwarded from router to router until it reaches the destination router, which delivers it to the final destination host.
The Internet Protocol (IP) is the foundational protocol of the TCP/IP architecture that all computers on the Internet use to communicate. There are two main versions of IP - IPv4, the currently used version, and IPv6 which is intended to replace IPv4. An IP address uniquely identifies a device on the network and consists of a network portion and host portion. IP allows for fragmentation of packets but does not guarantee delivery. Subnetting allows a single network to be divided into multiple logical subnets to improve routing and management.
This document provides an introduction to computer networks and IP addressing. It discusses the history of computer networks and the development of networking models like OSI and TCP/IP. IP addresses are unique addresses that allow devices to communicate on a network. The document describes the different classes of IP addresses (A, B, C, D, E) and how they divide the 32-bit address space. It also explains the concepts of network IDs, host IDs, subnet masks, and how subnetting can be used to logically divide a large network into smaller subnetworks.
The document discusses the role and functions of the Network layer (OSI Layer 3) in data networks. It examines the Internet Protocol (IP) as the most widely used Network layer protocol. IP provides connectionless and best-effort delivery of data packets across networks. The document also discusses how networks are logically grouped and addressed in a hierarchical manner to allow communication between large numbers of devices across interconnected networks. Key concepts covered include addressing, routing, encapsulation, next hop forwarding, and the use of static and dynamic routing to build routing tables.
The document discusses the key responsibilities and functions of the network layer in computer networking. The network layer is responsible for getting packets from their source to their destination across multiple hops and routers. It must choose appropriate paths through the network topology and balance traffic loads across lines and routers. The network layer provides either a connectionless or connection-oriented service and uses different packet forwarding mechanisms depending on the chosen service.
The document discusses topics related to the network layer, including:
1. It describes virtual circuits and datagrams, which are two methods for transferring data across networks.
2. It covers IPv4 addressing concepts such as address space, notations, classful and classless addressing, subnetting, and network address translation.
3. It provides an overview of additional network layer topics like IPv6 addressing, routing algorithms, internet control protocols, and routing protocols.
This document provides an overview of networking concepts including network types, medium access control protocols, TCP/IP protocol suite, addressing, Ethernet frames, ARP, and standards organizations. It begins with an agenda that lists these topics and includes diagrams to illustrate CSMA/CD, the OSI model, TCP/IP encapsulation, and Ethernet encapsulation. Examples are provided for different network devices, addressing formats and protocols.
Human computer Interaction ch1-the human.pdfJayaprasanna4
Human cognition and perception involve receiving sensory input, processing and storing information, and applying it through reasoning, problem-solving and skill. The key senses are vision, hearing, touch, smell and taste. Vision involves light being focused on the retina and processed in the brain to interpret signals about size, depth, brightness and color. Hearing detects sound waves that are processed to identify pitch, loudness and timbre. Memory has three types - sensory, short-term and long-term. Thinking uses reasoning like deduction and induction, and problem-solving applies knowledge through means-ends analysis or analogy. Emotion influences human capabilities and involves both cognitive and physiological responses.
computer Networks Error Detection and Correction.pptJayaprasanna4
This document discusses error detection and correction in data transmission. It covers the following key points:
- There are two main types of errors: single-bit errors and burst errors. Burst errors are more common in serial transmission.
- Error detection verifies data accuracy without having the original message. It uses redundancy like vertical and longitudinal redundancy checks. Cyclic redundancy checks use polynomial division to detect errors.
- Error correction automatically fixes certain errors. Single-bit error correction reverses the value of the altered bit. Hamming codes use additional redundant bits to detect and correct single-bit errors.
HUman computer Interaction Socio-organizational Issues.pptJayaprasanna4
This document discusses socio-organizational issues and stakeholder requirements in systems design. It covers topics such as organizational conflicts that can impact system acceptance, identifying stakeholder needs in context, and socio-technical models to understand human and technical requirements. Methodologies covered include soft systems methodology to take a broader view, participatory design to involve users, and ethnographic research to study users unbiasedly.
human computer Interaction cognitive models.pptJayaprasanna4
This document discusses cognitive models used to represent users of interactive systems. It describes hierarchical models that represent a user's task and goal structure, as well as linguistic models that represent the user-system grammar. GOMS and CCT are two common cognitive models discussed in detail, with both modeling a user's goals, operators, and methods in a hierarchical structure. The document also covers Keystroke-Level Modeling (KLM) which uses cognitive understandings to predict user performance times for simple tasks.
World wide web and Hyper Text Markup LanguageJayaprasanna4
The document discusses hypertext, multimedia, and the World Wide Web. It covers understanding hypertext and how it differs from linear text through its non-linear structure and links. It also discusses finding information on the web through navigation, structure, bookmarks and search engines. Finally, it outlines some of the underlying web technologies including protocols, servers, clients and networking that allow information to be delivered and accessed on the internet.
The Monte Carlo method uses randomness to solve deterministic problems. It relies on the law of large numbers, which states that averaging a large number of random samples approximates the expected value. The method involves:
1) Defining a probability space with many random points;
2) Applying the constraints of the problem;
3) Discriminating between points inside and outside the constraints;
4) Using the internal points to define the solution space. The more points used, the more accurate the simulation.
The document discusses activity planning for projects. It covers estimating activity durations, developing detailed activity schedules, and identifying risks. A project consists of related activities, and finishes when all activities are complete. Activities must have clear start and end points and estimated durations. Network diagrams like CPM and PERT are used to plan activity sequences and identify the critical path, which determines the overall project duration. Slack time and floats help schedule activities and identify scheduling flexibility.
The document discusses various techniques for estimating software effort, including parametric models, expert judgment, analogy, and bottom-up and top-down approaches. It describes the bottom-up approach as breaking a project into tasks, estimating effort for each, and summing totals. Top-down uses parametric models relating effort to system size and productivity factors. Function point analysis and COSMIC function points are presented as top-down methods to measure system size independently of programming language.
The document discusses activity planning for projects. It covers estimating activity durations, developing detailed activity schedules, and identifying risks. A project consists of related activities, and finishes when all activities are complete. Activities must have clear start and end points and estimated durations. Network diagrams like CPM and PERT are used to plan activity sequences and identify the critical path, which determines the overall project duration. Slack time and floats help schedule activities and identify scheduling flexibility.
This document outlines the objectives and content of the IT8075 Software Project Management course. The course aims to teach students how to plan, manage, and deliver successful software projects. It covers topics such as project planning, estimation techniques, risk management, project monitoring and control, and people management. The course is divided into 5 units which cover areas such as the software development life cycle, effort estimation methods, scheduling, risk analysis, and staff management in projects. The intended learning outcomes include understanding basic project management principles and gaining knowledge of processes, estimation, risk identification, and using principles to define project structure and track progress.
Path-vector routing uses spanning trees to determine routes between sources and destinations based on policies imposed by each source rather than least-cost. BGP is an interdomain routing protocol that uses path-vector routing, with each AS advertising routing information to neighboring ASes. BGP ensures loop-free paths by enumerating the list of ASes in a path and allows ASes to apply local policies to select the best routes.
This document discusses multicasting and multicast routing protocols. It begins with an introduction to multicasting versus unicasting. It then discusses multicast trees, including source-based trees and group-shared trees. It provides overviews of several multicast routing protocols: DVMRP, a distance-vector protocol; MOSPF, an extension of OSPF; and CBT, which uses a rendezvous-point tree with a core router. Key concepts like reverse path forwarding and pruning/grafting to support dynamic membership are also summarized.
This document provides an introduction to computer networks and the fundamental concepts of data communication. It discusses the key components of data communication systems including messages, senders, receivers, transmission medium, and protocols. It also describes different types of data representation and data flow including simplex, half-duplex, and full-duplex. Additionally, it covers network criteria such as performance, reliability, and security. Finally, it discusses various topics in computer networks including physical topologies (e.g. mesh, star, bus, ring), categories of networks (LAN, MAN, WAN), and their characteristics.
This document discusses error detection and correction techniques used in data communication. It describes different types of errors like single-bit errors and burst errors. It then explains various error detection methods like vertical redundancy check (VRC), longitudinal redundancy check (LRC), cyclic redundancy check (CRC), and checksum that work by adding redundant bits. The document also covers error correction techniques like single-bit error correction using Hamming code which allows detecting and correcting single-bit errors.
This document discusses different types of connecting devices used to connect local area networks (LANs) or segments of LANs. It describes five categories of connecting devices based on the layer of the Internet model in which they operate: 1) passive hubs and repeaters that operate below or at the physical layer, 2) bridges that operate at the physical and data link layers, 3) routers that operate at the physical, data link, and network layers, and 4) gateways that can operate at all five layers. Specific devices like hubs, bridges, and routers are explained in terms of their functions, capabilities, and how they differ from each other.
The document contains questions and answers related to computer networks:
1. The presentation layer of the OSI model performs translation, encryption, and compression functions.
2. A sine wave with a frequency of 6 Hz has a period of 0.1515 seconds.
3. In stop-and-wait protocol, the sender transmits one frame and waits for an acknowledgment before sending the next frame. If no acknowledgment is received within a timeout period, the sender retransmits the original frame.
The document discusses session tracking techniques in servlets. It describes four main techniques: cookies, hidden form fields, URL rewriting, and HTTP sessions. Cookies are the simplest technique and involve assigning a unique session ID to each client as a cookie. Hidden form fields maintain state by storing information in hidden form fields and transmitting it across requests. URL rewriting appends a session ID to the URL. HTTP sessions involve saving client-specific information on the server side in an HTTP session object.
JDBC provides a standard Java API for accessing databases. It allows Java programs to connect to databases, send SQL statements, and process the results. The key steps in using JDBC include: 1) loading the appropriate JDBC driver, 2) establishing a connection, 3) creating statements to query the database, 4) processing result sets, and 5) closing connections. JDBC supports both two-tier and three-tier architectures and allows transactions to group SQL statements.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
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Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
2. 2
Where is the network layer?
a)There are 7 layers from OSI model and 5 layers
from TCP/IP model (as discussed previously!)
b)From OSI, the Network layer rests between the
upper layer called the Transport layer and the lower
layer called the Data Link Layer.
c)From the TCP/IP model, the Network layer is
called the Internet layer and it rests between the
upper Transport layer and the lower Host to
Network layer.
5. 5
Network layer duties
• The key is interconnecting different networks (various
LAN technologies, telephone network, satellite link,
ATM networks etc.) and making them look the same to
the upper layer; i.e. logical gluing of heterogeneous
physical networks together to look like a single network
to the Transport & Application layer.
• Additional notes: The transport layer should not be
worried about the underlying physical network !
6. 6
Network layer duties
• The addresses must be uniquely and universally define the
sole connection of a (host/router/machine/device/user) to the
internet. Two devices on the internet can never have the
same address. (Address per connection)
We cannot use the data link layer addresses !! Because these
addresses depend on the technology used in the data link layer.
Remember, network layer is independent of the data link layer.
7. 7
Network layer duties
• Network layer encapsulates packets received from upper
layer protocols and makes new packets. (Re-packaging).
• This is a task common to all layers.
• In the Internet model, packetizing is done by network layer
protocol called IP – Internetworking Protocol.
• The Protocol Data Units (PDU’s) coming from the transport
layer must be placed in network-layer packets and sent to
the data-link layer.
8. 8
Network layer duties
• A packet can travel through different networks. Each router
decapsulates the IP datagram from the received frame, processes
it and then encapsulates it in another frame. The format & size
depend on the physical network.
• Remember, the network layer must be able to operate on top of
any data-link layer technology (Ethernet, Fast Ethernet, ATM etc.).
All these technologies can handle a different packet length.
• The network layer must be able to fragment transport layer PDUs
into smaller units so that they can be transferred over various data-
link layer technologies.
9. 9
Network layer duties
• Now that you have your network layer packet, where
do you send it ? Each packet reaches its destination via
several routes.
• So, which route is suitable or optimum? Issue of
speed, reliability, security etc. (routing algorithm)
• Packet cannot choose the route; the routers
connecting the LANs/WANs makes this decision.
• (refer Chap-19 of Forouzan’s book).
10. 10
How can data be exchanged between networks?
Internetworking
They need to be connected via routers/links to make an
internetwork.
• The above internetwork is made of 5 networks: 4 LANs and 1 WAN.
• E.g. If host A needs to send a data packet to host D, the packet
needs to go from A to S1, then from S1 to S3, and finally from S3 to
D. Therefore the packet passes through 3 links.
11. 11
Internetworks
link-1 link-2 link-3
• To solve the problem of delivery thru several links, the
network layer was designed and responsible for host-to-host
delivery and for routing the packets thru different routers.
MAC layer protocol
• Problem: how does S1 know that they should send out from f3 after packet
arrive at f1 from A? (No provision in data-link layer to help S1 making the
decision and the frame only contains the MAC addresses-pair of 1st link)
12. 12
Network layer at the Source
The source network layer receives data
from transport layer, adds the universal
addresses of host A and host D.
Network layer at source is responsible to create a packet that
carrier 2 universal addresses: Destination add. & Source add.
Make sure packet size
correct & if too big, the
packet is fragmented.
Also, it can add fields for
error control.
13. 13
Network layer at the Router
Network layer at the router is responsible for routing the packet.
When a packet arrives, the router finds the interface from which
the packet must be sent using routing table.
Another
fragmentation
is possible if
necessary
14. 14
Network layer at the Destination
Network layer at the Destination is responsible for address verification;
it makes sure that Destination address on the packet is the same as the
address of the receiving host.
It also checks for
data corruption
waits until all fragments
arrive and reassembles
them.
15. 15
Switching/Routing Mechanism
Used in computer networks
and (also in modern
telephone networks).
Packets of bits (not lines)
are switched!
Used in telephone networks
for more than 100 years. A
physical link is dedicated
between Source and
Destination. Data can be
sent as a stream of bits
without the need for
packetising
(Also called
Connection-oriented
networking)
(Also called
Connectionless
networking)
20. 20
Internet Protocol (IP)
IP uses connectionless network-layer protocol.
IP is based on datagram switching/routing.
IP is unreliable !!
Don’t care how, as long as it arrives!!
22. 22
Change the following IP address from binary
notation to dotted-decimal notation.
10000001 00001011 00001011 11101111
Solution
129.11.11.239
Example
23. 23
Change the following IP address from
dotted-decimal notation to binary notation.
111.56.45.78
Solution
01101111 00111000 00101101 01001110
Example
24. 24
IP-Addressing
• The general identifier used in network layer to identify each device
connected to the Internet is called the Internet address or IP address.
• Two types ID: Network Address & Host Address.
• In IPv4, an IP address is a 32-bit binary address (4-bytes) that
uniquely and universally defines the connection of a host or a router
to the Internet. (Universal in the sense that the addressing system
must be accepted by any host that wants to be connected to Internet).
• Each IP address is unique and only defines 1 connection to the
Internet. Two devices on the internet can never have the same
address at the same time. (referring to IP Public addresses).
25. 25
IP-Addressing
• Two types of IP addressing: Classful vs. Classless
• When a packet needs to be sent from s host to destination, it needs
to pass from one node to the next. The network layer provides only
host-to-host addressing; the data-link layer needs physical MAC
addresses for node-to-node delivery.
• Method to map these two addresses: ARP – Address Resolution
Protocol.
32. 32
Classful Addresses
Classful addressing in IP is both inflexible and inefficient !
allows 127 networks and 16 777 214 hosts on each network
allows 16384 networks and 65534 hosts on each network
allows 2 097 152 networks and 254 hosts on each network
7 bits = 27 -1: exclude 0.0.0.0
0.0.0.0 to
127.255.255.255
128.0.0.0 to
191.255.255.255
192.0.0.0 to
223.255.255.255
24 bits = 224 -2: exclude 1st and last IP
14 bits = 214 16 bits = 216 -2: exclude 1st and last IP
21 bits = 221 8 bits = 28 -2: exclude 1st and last IP
Note: In each network, the 1st IP address is the Network Address (e.g. 73.0.0.0)
and the last IP address is for special purpose (e.g. 73.255.255.255) .
33. 33
Classful Addressing
a) Unicast address: one source to one destination; Class A, B & C.
b) Multicast address: one source to a group of destination: only as
destination address not source address; Class-D.
c) IP addresses in class A, B, C are divided into different length of:
Network-ID (netid) and Host-ID (hostid)
d) Classes and Blocks concept: - for example:
In class-A, 1st block covers from 0.0.0.0 to 0.255.255.255 (net-ID 0)
2nd block covers from 1.0.0.0 to 1.255.255.255 (net-ID 1)
last block covers from 127.0.0.0 to 127.255.255.255 (net-ID 127)
• Note that: block = number of available networks in each class
• One problem with classful addressing is that each class is divided
into a fixed number of blocks with fixed size. (read Forouzan’s text)
• Plenty of IP addresses wasted!!! in classful addressing method.
34. 34
128 Blocks in class A
1st IP used to identify organisation
to the rest of Internet
Last IP reserved for special
purpose; not allowed to use
Millions of class A addresses are wasted.
3 bytes
= 224
35. 35
16384 Blocks in class B
Many of class B addresses are wasted.
Class B for midsize organisation.
16384 organizations are class-B
16 blocks for private addressees
leaving 16368 blocks
36. 36
2,097,152 Blocks in class C
256 blocks for private addressees
leaving 2,096,896 blocks
Class C for small organisation.
Limited IP address in each blocks,
which is smaller than the needs of
most organisations
37. 37
Class D addresses
are used for multicasting;
there is only
one block in this class.
Class E addresses are reserved
for special purposes;
most of the block is wasted.
38. 38
Network Addresses
The network address is the first address.
The network address defines the network
to the rest of the Internet.
Given the network address, we can find
the class of the address, the block, and the
range of the addresses in the block
39. 39
Figure 4-13
Network addresses
In classful addressing, the network address
(the first address in the block)
is the one that is assigned to the organization.
40. 40
Example
Given the network address 17.0.0.0, find the
class, the block, and the range of the
addresses.
Solution
The class is A because the first byte is between 0 and 127.
The block has a netid of 17.
The addresses range from 17.0.0.0 to 17.255.255.255.
41. 41
Example
Given the network address 132.21.0.0, find
the class, the block, and the range of the
addresses.
Solution
The class is B because the first byte is between 128 and 191.
The block has a netid of 132.21.
The addresses range: 132.21.0.0 to 132.21.255.255.
42. 42
Example
Given the network address 220.34.76.0, find
the class, the block, and the range of the
addresses.
Solution
The class is C because the first byte is between 192 and 223.
The block has a netid of 220.34.76.
The addresses range from 220.34.76.0 to 220.34.76.255.
43. 43
Sample Internet
Note: When it
comes to routing,
the outside world
recognises the
network via network
address, not the
individual host-IPs
44. 44
The network address is the
beginning address of each block.
It can be found by applying the default
mask to any of the IP addresses in the block.
It retains the netid of the block
and sets the hostid to zero.
We must not apply the default mask
of one class to an address belonging
to another class.
Network Addresses
46. 46
Mask
A mask is a 32-bit binary number or 4-bytes that
gives the first address in the block (the network
address) when bitwise ANDed with an address in
the block.
47. 47
Default class A mask is 255.0.0.0
Default class B mask is 255.255.0.0
Default class C mask is 255.255.255.0
Default Mask
48. 48
Example
Given the address 23.56.7.91 and the default
class A mask, find the beginning address
(network address).
Solution
The default mask is 255.0.0.0, which means
that only the first byte is preserved
and the other 3 bytes are set to 0s.
The network address is 23.0.0.0.
49. 49
Example
Given the address 132.6.17.85 and the default
class B mask, find network address.
Solution
The default mask is 255.255.0.0, which means
that the first 2 bytes are preserved
and the other 2 bytes are set to 0s.
The network address is 132.6.0.0.
50. 50
Example
Given the address 201.180.56.5 and the class
C default mask, find the network address.
Solution
The default mask is 255.255.255.0,
which means that the first 3 bytes are
preserved and the last byte is set to 0.
The network address is 201.180.56.0.
51. 51
IP-Addressing/Subnetting
a) IP address designed with 2 levels of hierarchy: network-ID & host-ID.
b) However, often organisation needs to assemble the hosts into groups:
the network needs to be divided into several subnetworks (subnets);
hence requires 3 levels of hierarchy. (netid: subnetid : hostid)
c) The outside world only knows the organisation by its network address.
Inside the organisation each sub-network is recognised by its sub-
network address.
d) In subnetting, a network is divided into several smaller groups that
have its own subnet address depends on the hierarchy of subnetting
but still appear as a single network to the rest of the Internet.
e) The question is how a router knows whether it is a network address or
a subnet? The key is using the subnet mask. (similar to def. mask).
f) Only the network administrator knows about the network address and
subnet address but router does not. External router has routing table
based on network addresses; Internal router has routing table based on
subnetwork addresses.
58. 58
Given an IP address, we can find the subnet
address the same way we found the network
address in the previous chapter.
We apply the mask to the address.
We can do this in two ways:
straight or short-cut.
Finding the Subnet Address
59. 59
Straight Method
In the straight method, we use binary notation for both the
address and the mask and then apply the AND operation to
find the subnet address.
Short-Cut Method
** If the byte in the mask is 255, copy the byte in the address.
** If the byte in the mask is 0, replace the byte in the address with 0.
** If the byte in the mask is neither 255 nor 0, we write the mask and
the address in binary and apply the AND operation.
60. 60
Example
What is the sub-network address if the destination address
is 200.45.34.56 given that the subnet mask is
255.255.240.0?
Solution
11001000 00101101 00100010 00111000
11111111 11111111 11110000 00000000
11001000 00101101 00100000 00000000
The subnetwork address is 200.45.32.0.
61. 61
Example
What is the sub-network address if the destination address
is 19.30.80.5 and the mask is 255.255.192.0?
Solution Answer: Subnet Address = 19.30.64.0
62. 62
Comparison of a default mask and
a subnet mask
The number of subnets must be
a power of 2.
63. 63
Example
A company is granted the site address 201.70.64.0 (class C). The
company needs six subnets. Design the subnets.
Solution
The number of 1s in the default mask is 24 (class C).
The company needs six subnets. Since 6 is not a power of 2, the next
number that is a power of 2 is 8 (23). That means up to 8 subnets.
Hence, we need 3 more ‘1’s in the subnet mask =
11111111.11111111.11111111.11100000 or 255.255.255.224
The total number of 1s in the subnet mask is 27 (24 + 3).
Since the total number of 0s is 5 (32 - 27).
The number of addresses in each subnet is 25
(5 is the number of 0s) or 32.
65. 65
Example
A company is granted the site address 181.56.0.0 (class B). The
company needs 1000 subnets. Design the subnets.
Solution
The number of 1s in the default mask is 16 (class B).
The company needs 1000 subnets. Since it is not a power of 2, the
next number is 1024 (210). We need 10 more 1s in the subnet mask.
The total number of 1s in the subnet mask is 26 (16 + 10).
The total number of 0s is 6 (32 - 26).
66. 66
Solution (Continued)
The submask is
11111111 11111111 11111111 11000000
or
255.255.255.192.
The number of subnets is 1024.
The number of addresses in each subnet is 26
(6 is the number of 0s) or 64.
68. 68
Subnetting in Classful Addresses
10000000 00010100 00000000 00000000
Network Prefix Host Suffix
Class B addess
Subnetting with /20 mask Network Prefix
Subnet
ID
Host ID
75. 75
Classless Addressing
a) The idea of Classful addressing has created many problems.
b) Until mid-1990s, a range of addresses meant a block of addresses
in class A, B or C.
c) The minimum number of addresses granted to an organisation as
256 (class C); the maximum is 16,777,216 (class A).
d) In between these limits, an organisation could have a class B block
or several class C blocks. However, the choices were limited.
e) In addition, what about the small business that needed only 16
addresses? Or a household that needed only 2 addresses?
f) Solution: Classless addressing (from 1996)
g) The idea is to have variable-length blocks that belongs to no class.
76. 76
Number of Addresses in a Block
There is only one condition on the number of
addresses in a block; it must be a power of 2
(2, 4, 8, . . .).
For exmaple, a household may be given a
block of 2 addresses. A small business may be
given 16 addresses. A large organization may
be given 1024 addresses.
Classless Addressing Rules:
77. 77
Beginning Address
The beginning address must be evenly divisible
by the number of addresses.
For example, if a block contains 4 addresses, the
beginning address must be divisible by 4. If the
block has less than 256 addresses, we need to
check only the rightmost byte. If it has less than
65,536 addresses, we need to check only the two
rightmost bytes, and so on.
Classless Addressing Rules:
78. 78
Example
Which of the following can be the beginning address of a
block that contains 16 addresses?
205.16.37.32
190.16.42.44
17.17.33.80
123.45.24.52
Solution
The address 205.16.37.32 is eligible because .32 is
divisible by 16. The address 17.17.33.80 is eligible
because 80 is divisible by 16.
79. 79
Example
Which of the following can be the beginning address of a
block that contains 1024 addresses?
205.16.37.32
190.16.42.0
17.17.32.0
123.45.24.52
Solution
To be divisible by 1024, the rightmost byte of an
address should be 0 and the second rightmost byte
must be divisible by 4 (2 bits of 2nd byte needed).
Only the address 17.17.32.0 meets this condition.
80. 80
Slash notation
Slash notation is also called CIDR notation/prefix
length represented using ‘1’, as masking.
CIDR = Classless InterDomain Routing
To enable the variable-length blocks, the slash notation is
introduced
The remaining unmasked ‘0’is referred to the suffix length
10000000 00010100 00000000 00000000
Network Prefix Host Suffix
Class B address
Subnetting with /20 mask Network Prefix
Subnet
ID
Host ID
= 128.20.0.0/20
81. 81
CIDR Addressing in Internet Protocol
CIDR allows each IP address to have a different length of network
ID and host ID. In CIDR each IP address is assigned a 32-bit mask
to extract the network ID.
128.192.111.202 / 29
10000000 01101111 11000000 11001010
11111111 11111111 11111111 11111000
10000000 01101111 11000000 11001000
Network ID: 128.192.111.200
Counts the
number of ‘1’
in this case 29
from the leftmost
The prefix length is 29 and suffix length is 3
82. 82
153.237.108.227 /19
10011001 11101101 01101100 11100011
11111111 11111111 11100000 00000000
10011001 11101101 01100000 00000000
Network ID: 153.237.96. 0
Counts the
number of ‘1’ – in
this case 19 from
the left
CIDR Addressing in Internet Protocol
The prefix length is 19 and suffix length is 13
83. 83
Example
A small organization is given a block with the beginning address
and the prefix length 205.16.37.24/29 (in slash notation). What is
the range of the block?
Solution
The beginning address is 205.16.37.24. To find the last address we
keep the first 29 bits and change the last 3 bits to 1s.
Beginning:11001111 00010000 00100101 00011000
Ending : 11001111 00010000 00100101 00011111
There are only 8 addresses in this block.
Alternatively, we can argue that the length of the suffix is 32 - 29
or 3. So there are 23 = 8 addresses in this block. If the first address
is 205.16.37.24, the last address is 205.16.37.31 (24 + 7 = 31).
84. 84
A block in classes A, B, and C
can easily be represented in slash
notation as: A.B.C.D/ n
where n is either
8 (class A), 16 (class B), or
24 (class C).
85. 85
Example
What is the network address if one of the addresses is
167.199.170.82/27?
Solution
The prefix length is 27, which means that we must
keep the first 27 bits as is and change the remaining
bits (5) to 0s. The 5 bits affect only the last byte.
The last byte is 01010010. Changing the last 5 bits
to 0s, we get 01000000 or 64. The network address
is 167.199.170.64/27.
86. 86
Example
An organization is granted the network address block of
130.34.12.64/26. The organization needs to have four subnets.
What are the subnet addresses and their range for each subnet?
Solution
The suffix length is 6 (32-26). This means the total number of
addresses in the block is 64 (26). If we create four subnets, each
subnet will have 16 addresses. Let us first find the subnet prefix
(subnet mask). We need four subnets, which means we need to add
two more ‘1’s to the site prefix /26. The subnet prefix is then /28.
Subnet 1: 130.34.12.64/28 to 130.34.12.79/28.
Subnet 2 : 130.34.12.80/28 to 130.34.12.95/28.
Subnet 3: 130.34.12.96/28 to 130.34.12.111/28.
Subnet 4: 130.34.12.112/28 to 130.34.12.127/28.
90. 90
Example
An ISP is granted a block of addresses starting with
190.100.0.0/16. The ISP needs to distribute these
addresses to three groups of customers as follows:
1. The first group has 64 customers; each needs 256 addresses.
2. The second group has 128 customers; each needs 128 addresses.
3. The third group has 128 customers; each needs 64 addresses.
Design the subblocks and give the slash notation for each
subblock. Find out how many addresses are still available
after these allocations.
91. 91
Solution
Group 1
For this group of 64 customers, each customer needs 256
addresses. This means the suffix length is 8 (28 = 256). The
prefix length is then 32 - 8 = 24.
01: 190.100.0.0/24 190.100.0.255/24
02: 190.100.1.0/24 190.100.1.255/24
…………………………………..
64: 190.100.63.0/24190.100.63.255/24
Total = 64 256 = 16,384
92. 92
Solution (Continued)
Group 2
For this group of 128 customers, each customer needs 128
addresses. This means the suffix length is 7 (27 = 128). The
prefix length is then 32 - 7 = 25. The addresses are:
001: 190.100.64.0/25 190.100.64.127/25
002: 190.100.64.128/25 190.100.64.255/25
…………………………………..
127: 190.100.127.0/25 190.100.127.127/25
128: 190.100.127.128/25 190.100.127.255/25
Total = 128 128 = 16,384
93. 93
Solution (Continued)
Group 3
For this group of 128 customers, each customer needs 64
addresses. This means the suffix length is 6 (26 = 64). The
prefix length is then 32 - 6 = 26.
001:190.100.128.0/26 190.100.128.63/26
002:190.100.128.64/26 190.100.128.127/26
…………………………
128:190.100.159.192/26 190.100.159.255/26
Total = 128 64 = 8,192
94. 94
Solution (Continued)
Number of granted addresses: 65,536
Number of allocated addresses: 40,960
Number of available addresses: 24,576
The available addresses range from:
190.100.160.0 190.100.255.255
Total = 96 256 = 24,576
99. 99
Router - Gateway
a) The router provides a gateway through which hosts on one
network can communicate with hosts on different networks.
b) Each interface on a router is connected to a separate network.
An IP address assigned to the interface identifies which local
network is connected directly to it.
101. 101
Why Private Addresses?
a) All hosts that connect directly to the Internet require a unique public
IP address. Due to finite number of 32-bits structure in IPv4 , there is
a risk of running out of IP addresses. One solution was to reserve
some private addresses for use exclusively inside an organization.
b) This allows hosts within an organization to communicate with one
another without the need of a unique public IP address. Therefore, the
same set of private addresses can be used by multiple organizations.
Private addresses are not routed on the Internet and will be quickly
blocked by an ISP router.
c) The use of private addresses can provide a measure of security since
they are only visible internally on the local network, and outsiders
cannot gain direct access to the private IP addresses.
d) Need Network Address Translation (NAT) Protocol to link the private
address to the public address or vice versa.
108. 108
Supernetting
a) Although class A and B addresses are almost depleted, Class
C addresses are still available.
b)However, the size of a class C block with a maximum
number of 256 addresses may not satisfy the needs of an
organisation.
c) One solution is supernetting.
d)In supernetting, an organisation can combine several calss C
blocks to create a large range of addresses.
e) In order words, several networks are combined to create a
supernetwork. This is done by applying a set of class C
blocks instead of just one.
110. 110
Rules:
** The number of blocks must be a power of 2
i.e: (2, 4, 8, 16, . . .).
** The blocks must be contiguous in the address
space (no gaps between the blocks).
** The third (3rd) byte of the first (1st) address in the
superblock must be evenly divisible by the number
of blocks. In other words, if the number of blocks is
N, the third byte must be divisible by N.
111. 111
Example
A company needs 600 addresses. Which of the following set of
class C blocks can be used to form a supernet for this company?
198.47.32.0 198.47.33.0 198.47.34.0
198.47.32.0 198.47.42.0 198.47.52.0 198.47.62.0
198.47.31.0 198.47.32.0 198.47.33.0 198.47.52.0
198.47.32.0 198.47.33.0 198.47.34.0 198.47.35.0
a.
b.
c.
d.
Solution
a: No, there are only three blocks.
b: No, the blocks are not contiguous.
c: No, 31 in the first block is not divisible by 4.
d: Yes, all three requirements are fulfilled.
112. 112
In subnetting,
we need the first address of the subnet
and the subnet mask to
define the range of addresses.
In supernetting,
we need the first address of the supernet
and the supernet mask to
define the range of addresses.
Vital notes: Supernetting
114. 114
Example
We need to make a supernetwork out of 16 class C
blocks. What is the supernet mask?
Solution
We need 16 blocks. For 16 blocks we need to change four
1s to 0s in the default mask. So the mask is
11111111 11111111 11110000 00000000
or
255.255.240.0
Class C mask is defaulted with 24 of ‘1’ is
11111111 11111111 11111111 00000000
115. 115
Example
A supernet has a first address of 205.16.32.0 and a supernet mask
of 255.255.248.0. A router receives 3 packets with the following
destination addresses:
205.16.37.44
205.16.42.56
205.17.33.76
Solution
We apply the supernet mask to find the beginning address.
205.16.37.44 AND 255.255.248.0 205.16.32.0
205.16.42.56 AND 255.255.248.0 205.16.40.0
205.17.33.76 AND 255.255.248.0 205.17.32.0
Only the first address belongs to this supernet.
Q: Which packet belongs to the supernet?
116. 116
Example
A supernet has a first address of 205.16.32.0 and a
supernet mask of 255.255.248.0. How many blocks are in
this supernet and what is the range of addresses?
Solution
The supernet has 21 1s. The default mask has 24
1s. Since the difference is 3, there are 23 or 8
blocks in this supernet. The blocks are 205.16.32.0
to 205.16.39.0. The first address is 205.16.32.0.
The last address is 205.16.39.255.
118. 118
Model of Internetworking delivery
a) Access Networks (LAN based)
b) Interconnection/Transit Networks (WAN based)
Although in this schematic the interconnection
is only via one WAN a real world internet
delivery would be by multiple WANs.
Source LAN
Transit WAN
(‘Backbone’)
Destination
LAN
Gateway
Gateway
120. 120
WAN - Features
a) Long distance transmission (via serial connection).
b) Typically point to point (PPP) links.
c) Backbones within networks or interconnecting networks.
d) WANs can either be circuit switched or packet switched.
- The telephony network (PSTN) is an example of a circuit switched network.
(Voice traffic networking is migrating away from the PSTN to packet switched
networks) – not VoIP.
- The Internet is the dominant packet switched network.
Packet switching comes in two flavours: datagram of which the Internet is the pre-
eminent example and virtual circuit of which ATM and frame relay are examples.
Network Models
122. 122
LAN - Features:
a) Provides connectivity at a local level – within an office,
within in a building, within a small campus.
b) Limited coverage distance. (depends on technologies)
c) Utilizes medium access control (MAC) protocols.
d) Operates over shared transmission links. (CSMA/CD or
OFDM)
e) Mostly based on Ethernet Technology (Fast-Ethernet
interfaces).
f) The Ethernet IEEE802.3 is the pre-eminent wired LAN MAC
protocol.
g) The WiFi IEEE802.11x is the pre-eminent wireless LAN
MAC protocol.
125. 125
A fully connected mesh topology
MESH
L = n(n-1)/2
Advantages
No sharing (Dedicated link)
Robust
Secure (Dedicated link)
Easy fault identification
Disadvantages
Complex, Expensive, Bulky
All these are a function of the
large amount of cabling needed.
126. 126
A star topology connecting four stations
STAR
Advantages
Cheaper than mesh ( – but more
expensive than bus).
Flexible (change only requires the
addition or removal of one cable).
Robust in that failure of a cable
only results in a single station
loosing connectivity.
Easy fault identification
Disadvantages
Single point of failure at the hub.
Less secure.
The STAR can be configured as point to multipoint depending on the nature
of the hub but BUS is always a shared multipoint link.
128. 128
BUS
Advantages Ease of installation and low cost.
Disadvantages Performance is very poor under moderate to
heavy loading, single point of failure, poor security.
A bus topology
129. 129
A ring topology
RING Advantages
Easy to install
Flexible (adding
removing stations)
Self monitoring
(circulating token)
Disadvantages
Unidirectional
Single point of failure
Security
131. 131
Internetworking allows separate networks to exchange
data. The Internet connects networks nationally and
globally using TCP/IP protocols.
•The Internet (and the WWW) has revolutionized
many aspects of our daily lives.
•It has affected the way we do business as well as the
way we spend our leisure time.
•The Internet is a communication system that has
brought a wealth of information to our fingertips and
organized it for our use.
THE INTERNET
135. 135
Hierarchical Network
a) A good network structure need to be self-contained.
b) In networking, hierarchical design is used to group devices into
multiple networks that are organized in a layered approach. (this
layer concept is different from OSI layer)
c) It consists of smaller, more manageable groups that allow local
traffic to remain local.
d) Only traffic that is destined for other networks is moved to a
higher layer.
e) A hierarchical, layered design provides optimization of function
and increased speed and efficiency.
f) It allows the network to scale as required because additional local
networks can be added without impacting the performance of the
existing ones.
138. 138
Hierarchical Network
The hierarchical design has three basic layers:
– Access Layer - to provide connections to hosts in a Local Network.
– Distribution Layer - to interconnect various Local Networks.
– Core Layer - a high-speed connection between different Distribution
Layer devices.
139. 139
Network Devices in Hierarchical Network
Access Layer – Hubs or Switches (layer-2 device).
Distribution Layer – ISR or Router (layer-3 device).
Core Layer – high-speed Router, WAN devices.
141. 141
The term Local Area Network (LAN) refers to a local network, or a group of
interconnected local networks that are under the same administrative control.
In the early days of networking, LANs were defined as small networks that
existed in a single physical location. While LANs can be a single local
network installed in a home or small office, the definition of LAN has evolved
to include interconnected local networks consisting of many hundreds of
hosts, installed in multiple buildings and locations.
The important thing to remember is that all of the local networks within a LAN
are under one administrative control. Other common characteristics of LANs
are that they typically use Ethernet or wireless protocols, and they support
high data rates.
The term Intranet is often used to refer to a private LAN that belongs to an
organization, and is designed to be accessible only by the organization's
members, employees, or others with authorization.
So, what is LAN?
146. 146
Questions:
a) How many switches can you see?
b) How many hubs?
c) How many routers?
d) Is there a Core-layer in this diagram?
e) From the Access layer, how many individual small local
groups are there?
f) From the Distribution layer, how many LANs are there?
g) Is there a peer-to-peer connection?
147. 147
• There are many considerations that must be taken into
account when planning for a network installation.
• The logical and physical topology maps of the network
need to be designed and documented before the
networking equipment is purchased and the hosts are
connected.
• Some things to consider include:
1. Physical environment where the network will be installed:
• Temperature control: all devices have specific ranges of
temperature and humidity requirements for proper
operation
• Availability and placement of power outlets
Network Design and Planning:
148. 148
2. Physical configuration of the network:
• Physical location of devices such as routers, switches,
and hosts
• How all devices are interconnected
• Location and length of all cable runs
• Hardware configuration of end devices such as hosts
and servers
3. Logical configuration of the network:
• Location and size of broadcast and collision domains
• IP addressing scheme
• Naming scheme
• Sharing configuration
• Permissions
Network Design and Planning: