CU-MCA-SEM-I-Advanced Computer Networks-Second Draft

MASTER OF COMPUTER APPLICATIONS SEMESTER- I ADVANCED COMPUTER NETWORKS

CHANDIGARH UNIVERSITY Institute of Distance and Online Learning SLM Development Committee Prof. (Dr.) H.B. Raghvendra Vice- Chancellor, Chandigarh University, Gharuan, Punjab:Chairperson Prof. (Dr.) S.S. Sehgal Registrar Prof. (Dr.) B. Priestly Shan Dean of Academic Affairs Dr. Nitya Prakash Director – IDOL Dr. Gurpreet Singh Associate Director –IDOL Advisors& Members of CIQA –IDOL Prof. (Dr.) Bharat Bhushan, Director – IGNOU Prof. (Dr.) Majulika Srivastava, Director – CIQA, IGNOU Editorial Committee Prof. (Dr) Nilesh Arora Dr. Ashita Chadha University School of Business University Institute of Liberal Arts Dr. Inderpreet Kaur Prof. Manish University Institute of Teacher Training & University Institute of Tourism & Hotel Management Research Dr. Manisha Malhotra Dr. Nitin Pathak University Institute of Computing University School of Business © No part of this publication should be reproduced, stored in a retrieval system, or transmitted in any formor by any means, electronic, mechanical, photocopying, recording and/or otherwise without the prior written permission of the authors and the publisher. SLM SPECIALLY PREPARED FOR CU IDOL STUDENTS 2 CU IDOL SELF LEARNING MATERIAL (SLM)

First Published in 2021 All rights reserved. No Part of this book may be reproduced or transmitted, in any form or by any means, without permission in writing from Chandigarh University. Any person who does any unauthorized act in relation to this book may be liable to criminal prosecution and civil claims for damages. This book is meant for educational and learning purpose. The authors of the book has/have taken all reasonable care to ensure that the contents of the book do not violate any existing copyright or other intellectual property rights of any person in any manner whatsoever. In the event the Authors has/ have been unable to track any source and if any copyright has been inadvertently infringed, please notify the publisher in writing for corrective action CONTENTS Unit 1–Introduction To Networks............................................................................................. 5 Unit 2–Network Layer ........................................................................................................... 46 UNIT 3-The Routing Protocols .............................................................................................. 64 Unit 4-Transport Layer........................................................................................................... 80 UNIT 5-Transport Protocols................................................................................................... 98 3 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT 6-Application Layer ................................................................................................... 112 Unit 7-Mobile Computing .................................................................................................... 147 UNIT 8-Networks ................................................................................................................ 158 Unit 9-Architecture Of Mobile Computing ........................................................................... 173 Unit 10-Introduction To Wireless Communication System 1 ................................................ 184 Unit 11-Introduction To Wireless Communication System 2 ................................................ 200 Unit 12-MANET.................................................................................................................. 214 Unit 13-Ad-Hoc Mobility Models ........................................................................................ 229 Unit 14-Routing Protocols.................................................................................................... 244 Unit 15-SDN........................................................................................................................ 256 4 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT 1–INTRODUCTION TO NETWORKS STRUCTURE 1.0 Learning objectives 1.1 Introduction to networks 1.2 Model of basic communication 1.3 Uses of computer networks 1.4 Features of computer networks 1.5 Computer network architecture 1.6 Computer network components 1.7 Types of Computer networks 1.8 Internetwork Types 1.9 Definition of Topology 1.10 OSI model 1.11 Summary 1.12 Keywords 1.13 Learning Activity 1.14 Unit end questions 1.15 References 1.0 LEARNING OBJECTIVES After studying this unit, you will be able to:  Explain the basics of networks and its need  Outline the importance of Data communication  Describe the Design of computer network architecture  List the OSI model and its layers 1.1INTRODUCTION TO NETWORKS A computer network is a collection of devices linked together by a transmission media such as wires or cables. Computers, printers, scanners, and fax machines are examples of these gadgets.The goal of having a computer network is to transfer files from other devices through it. Nodes are a term used to describe these devices. A computer network is made up of five main components.

Figure 1.1 Five components of data communication Data or information that must be transported from one device to the other with a computer network is referred to as a message. SENDER: The sender is the equipment that has the information and requires to send it to other networked devices. RECEIVER: A receiver is a device that anticipates data from other network devices. TRANSMISSION MEDIA: We require a transmission media to carry data from one device to another, such as lines, cables, radio waves, and so on. PROTOCOL: A protocol is a set of guidelines that both the transmitter and the receiver agree on; without a protocol, two devices can be linked but cannot interact. We require a set of rules called protocol to establish a trustworthy connection or data sharing across two different devices. For example, web browsers utilise the http and https protocols to get and post data to the internet, while email services linked to the web use the SMTP protocol. The modern world is constantly changing. Data the way company and other daily affairs are conducted has altered as a result of communication and networking. They now rely heavily on computers and mobile devices. A network is a collection of devices that are commonly referred to as nodes and are connected via a media link. A node is a device that may send or receive information collected by other network nodes, such as a computer or printer. Communication channels are the linkages that connect the devices. A computer network is a type of telecommunication channel that allows us to share data with other computers or devices on the same network. It's also known as a Data Network. The 6 CU IDOL SELF LEARNING MATERIAL (SLM)

Internet is the best instance of a computer network. A data centre does not imply a system with a single Control Unit that is saved to several other systems. Not Computer Network, but Distributed System. A network is expected to fulfil a number of requirements, which are listed below: 1. Performance 2. Reliability 3. Scalability Performance of Computer Networks It can be measured in a variety of ways: • Transit time: The time it takes for a message to move from one machine to another. • Response time: This is the amount of time that passes between an inquiry and a response. Other approaches to assess performance include: • Software efficiency • Amount of users • Connected hardware's capability Reliability in Computer Networks It establishes the frequency with which network failures occur. The greater the number of failures, the less reliable the network becomes. Security in Computer Networks It refers to the safeguarding of data against unauthorised access or users. Data flows through multiple layers of the network while travelling, and data could be retrieved if necessary. As a result, one of the most significant characteristics of Networks is security. The Characteristics of a Good Network 1. Interpersonal Interaction: We can actually communicate and effortlessly with one another. Emails, discussion boards, video conferencing, and other services are all made possible via computer networks. 2. Resources can be decided to share: We can share physical assets like printers and scanners by giving them access on a network. 3. File and data sharing: Only authorised users are expected to access files over the network. 1.2 MODEL OF BASIC COMMUNICATION 7 CU IDOL SELF LEARNING MATERIAL (SLM)

To transfer data between two parties, a communication method is established. Communication among a computer1, a server, and a telephone, for example (through modem). Figure 1.2 Communication Model Source Model of Communication This equipment, such as telephones or personal computers, generates the data to be transferred. Transmitter as a communication model The data created by the data source is not transferred in its original form. The data is transformed and encoded by the transmitter into electromagnetic wavesor signals. Transmission System as a communication model. A transmission system can be as simple as a single transmission network or as complicated as a comprehensive network that connects source and destination. Receiver as a communication model The receiver sends the message from the transmission line and translates it into a format that the destination device can understand. Destination receives the input data from the receiver in this communication model. Communication of Information Data communication is the exchange of exists between different devices across a transmission media. The information is sent in the form of 0s and 1s. Wire cable is utilised as the communication medium. The communication system must be a member of a communication network in order to communicate data. There are two types of data communication: local and remote, which are explained below: Local Data Communication When the communication devices are all in the same geographical region, same building, or face-to-face, local communication occurs. Remote Data Communication Remote communication occurs over a long distance, implying that the devices are separated. The following characteristics can be used to assess the efficacy of a data communication: 1. Delivery: Deliveries must be made to the correct address. 2. Punctuality: Deliveries should be made on time. 3. Accuracy: The information provided should be correct. 8 CU IDOL SELF LEARNING MATERIAL (SLM)

1.3 USES OF COMPUTER NETWORK Resource sharing: Resource sharing refers to the sharing of materials such as programmes, printers, and data among users on a network without regard to the resource's or users physical location. Server-Client Model: The server-client model employs computer programming. A server is a computer that is used to store data and is managed by the network administrator. Clients are the devices that connect to the server remotely to access data. Communication medium: A computer network serves as a means of communication between users. For example, a corporation with multiple computers may have an email system that employees utilise on a daily basis. E-commerce: In enterprises, computer networks are also crucial. We'll be able to conduct business on the internet. Amazon.com, for example, is a web-based retailer. 1.4 FEATURES OF COMPUTER NETWORK Figure 1.3 Features of Computer Network 9 The following is a list of computer system features. CU IDOL SELF LEARNING MATERIAL (SLM)

 Fast communication  File sharing  Simple backup and rollback  Sharing of software and hardware  Security and Scalability  Reliability The rate of communication We can communicate quickly and efficiently over the network thanks to the network. We can do video calls, email messaging, and other things over the internet, for example. As a result, the computer network provides an excellent means of exchanging information and ideas. Sharing of files One of the most significant advantages of a computer network is the ability to share files. The computer network allows us to share files with one another. It's simple to roll back and back up. Because the records are located on a centrally situated core server. As a result, taking a backup from the primary server is simple. Sharing of software and hardware We can deploy the programs on the main server, allowing users to access them from anywhere. As a result, we won't have to install the software with every computer. Hardware can be shared in the same way. Security The network provides performance by adding that users have permission to access specific files and applications. Scalability Scalability refers to the ability to add new components to the network. The network must be scalable, allowing us to expand it by adding more devices. However, it reduces the connection speed and the data transmission pace, which raises the odds of an error occurring. The use of routing or power switches can solve this difficulty. Reliability In the event of a hardware breakdown, a computer system can use an alternative source for data communication. 1.5 COMPUTER NETWORK ARCHITECTURE 10 CU IDOL SELF LEARNING MATERIAL (SLM)

The physical and logical design of the software, hardware, protocols, and medium for data transfer is referred to as computer network architecture. Simply, it refers to how computers are arranged and duties are assigned to them. The following are the two types of network architectures that are used: Figure 1.4 Types of Networks  Peer-To-Peer network  Client/Server network Peer-To-Peer network  A peer-to-peer network is one in which all computers are connected and have equal privileges and obligations for data processing.  A peer-to-peer network is helpful for small groups of computers, usually up to ten.  There is no dedicated server in a peer-to-peer network.  Each computer is given special permissions for sharing resources;however, this can cause problems if the system with the source is down. Figure 1.5 Peer-to-Peer Networks 11 Advantages of Peer-To-Peer Network: CU IDOL SELF LEARNING MATERIAL (SLM)

 It is less expensive because it does not include a dedicated server.  If one computer fails, the remaining computers will continue to function.  Each computer manages itself, making it simple to set up and maintain. Disadvantages of Peer-To-Peer Network:  In the case of a peer-to-peer network, the centralised system is absent. As a result, it can't back up the data because it's different in different places.  It does have a security flaw because the device is self-managed. Client/Server Network  A client/server networking is a communication model that allows end users, referred to as clients, to service providers such as songs, videos, and other media from a central computer, referred to as the server.  The central controller is referred to as a server, while the rest of the network's PCs are referred to as clients.  A server handles all of the major tasks, such as computer and safety administration.  A server is in charge of all resources, including files, directories, printers, and so on.  A server connects all of the clients and allows them to communicate with one another. For instance, if client 1 wishes to communicate certain data to client 2, it must first obtain permission from the server. To begin communication with client 2, the server delivers the answer to client 1. Figure 1.6 Client/Server Network 12 Advantages of Client/Server network: CU IDOL SELF LEARNING MATERIAL (SLM)

 The centralised system is housed in a Client/Server network.  As a result, we can easily back up the data.  A Client/Server network features a physical server that boosts the system's overall performance.  Security is better in a Client/Server network since the shared resources are managed by a single server.  It also improves the pace with which resources are shared. Disadvantages of Client/Server network:  A client/server network is costly since it necessitates a server with a lot of memory.  A network operating system (NOS) is used by a server to give resources to clients, although the cost of NOS is very expensive.  It necessitates the hiring of a dedicated network operator to oversee all of the resources. 1.6 COMPUTER NETWORK COMPONENTS The key components required to instal the software are computer network components. NIC, switch, wire, hub, router, and modems are all significant network components. Some service offerings can be eliminated depending on the sort of network we need to instal. The wireless network, for example, does not require the use of a cable. The following are the main elements needed to set up a network:  Network interface card stands for network interface.  A network interface card (NIC) is a hardware component that connects a computer to another computer through a network. O It has a maximum throughput of 10,100 to 1000 Mb/s.  The MAC address, also known as the physical address, is stored on the network card chip and provided by the IEEE to uniquely identify each network card. The PROM stores the MAC address (Programmable read-only memory). There are two types of NIC: 1. Wired NIC 2. Wireless NIC 13 CU IDOL SELF LEARNING MATERIAL (SLM)

FIGURE 1.7 TYPES OF NIC WIRED NIC: The wired nic can be found on the motherboard. To transport data, wired nics require cables and connectors. The antenna for establishing a wireless network connection is housed in the wireless nic. The wireless nic, for example, is found in a laptop computer. Hub A hub is a piece of hardware that splits a network connection amongst numerous devices. When a computer seeks data from the network, the request is initially sent by cable to the Hub. This request will be disseminated to the overall infrastructure via Hub. All devices will check to see if the request is theirs or not. Otherwise, the application will be ignored. The Hub's procedure uses more bandwidth and restricts the quantity of data that can be sent. Hubs are no longer used and have been superseded by more modern computer and network components including such switches and routers. Switch A switch is a computer network hardware component that connects many devices. A Switch is more advanced than a Hub in terms of features. The Switch houses an updated table that determines whether or not data is transferred. Dependent on the site address in the incoming message, Switch sends the message to the right location. Unlike the Hub, a Change does not transmit the information to the whole network. It identifies the device to which the message will be sent. As a result, we may say that the switch establishes a direct link between the source and the destination. It boosts the network's performance. A router is a physical device that connects a local area network (LAN) to the internet. It receives, analyses, and forwards incoming packets to a different network.  A router is part of the OSI Reference Model's Layer 3 (Network layer).  Based on the information in the routing table, a router forwards the packet.  It selects the optimum path for packet transmission from among the available options. The following are some of the benefits of using a router: 14 CU IDOL SELF LEARNING MATERIAL (SLM)

Security: Data sent to the internet will travel the length of the cable, but only the device to which it has been addressed will be able to read it. Reliability: If the server stops working, the network falls down, and no other networks serviced by the router are affected. Network Performance The router improves the network's overall performance. Assume that a network of 24 workstations generates the same amount of traffic. This raises the network's traffic load. The router divides the single system into multiple networks, each with 12 workstations, halves the traffic burden. Modem  A modem is a piece of hardware that enables a computer to the internet via a phone connection.  Instead of being integrated into the motherboard, a modem is inserted in a PCI slot on the motherboard.  Modulator/Demodulator is the abbreviation for modulator/demodulator. It uses telephone lines to transform digital information into an analogue signal.  A modem can be categorised into the following groups based on performance and transmission rate differences:  Dial-up modem or standard PC modem  A cellular modem is a device that allows you to connect to the internet  Modem through cable Cables and Connectors A signal is transmitted by cable, which is a transmission medium. In transmission, there are 3 types of cables:  Cable with twisted pairs  Cable (coaxial)  A fibre-optic cable is a type of cable that transmits data over a long distance. 1.7 TYPES OF COMPUTER NETWORKS A computer network is a collection of computers that are linked together so that one computer can connect with another and share services, data, and applications. The size of a computer network can be classified. There are four primary types of computer networks: 15 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.8 Network Types  LAN(Local Area Network)  PAN(Personal Area Network)  MAN(Metropolitan Area Network)  WAN(Wide Area Network) LAN (Local Area Network)  A local area network (LAN) is a collection of computers connected in a small area, such as a building or an office.  A local area network (LAN) connects two or more computers using a communication means such as twisted - pair cable or coaxial cable.  It is less expensive since it is made up of low-cost components like hubs, network adapters, & ethernet cables.  In a Local Area Network, data is exchanged at an exceedingly fast rate.  A Local Area Network (LAN) gives a higher level of security. Figure 1.9 LAN Network 16 CU IDOL SELF LEARNING MATERIAL (SLM)

PAN(Personal Area Network) A Personal Area Network (PAN) is a network that is set up within a single person and normally has a range of 10 metres. The term \"Personal Area Network\" refers to a network that is used to connect personal computing devices.  The Personal Area Networks was first proposed by Thomas Zimmerman, a research scientist.  The Personal Area Network (PAN) covers a 30-foot radius. Figure 1.10 PAN Network THERE ARE TWO TYPES OF PERSONAL AREA NETWORK:  Wired Personal Area Network  Wireless Personal Area Network Figure 1.11 Types of PAN 17 CU IDOL SELF LEARNING MATERIAL (SLM)

WIRELESS PERSONAL AREA NETWORK (WPAN): Wpan is a wireless personal area network that is created utilising communication devices such as Wi-Fi and Bluetooth. It's a network with a short range. WIRED PERSONAL AREA NETWORK: A usb is used to construct a wired personal area network. PERSONAL AREA NETWORK (PAN) EXAMPLES: Body area network: a network that travels with a person is known as a body area network. A mobile network, for example, follows a person. Assume a person establishes a net connection and then establishes a link with another device in order to share data. Offline network: an offline network, often known as a home network, can be formed within the home. The purpose of a home network is to connect resources such as printers, computers, and televisions that are not linked to the internet. Small home office: it connects a variety of devices to the internet and a corporate network via a vpn A metropolitan area network (man) is a network that connects multiple lans to form a larger network that covers a greater geographic area. Man is used by government organisations to engage with citizens and private businesses. In man, many lans are linked together via a phone line line.rs-232, frame relay, atm, isdn, oc-3, adsl, and other protocols are commonly used in man. Its range is greater than that of a local area network (lan). USES OF METROPOLITAN AREA NETWORK:  The MAN protocol is used to communicate across businesses in a city.  It could be used to book an airline ticket.  It will be used at a city-based college.  It is also used for military communication. 18 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.12 MAN Network Wide Area Network Figure 1.13 WAN Network  A wide area network (WAN) is a network that spans a vast geographic area, such as many states or nations. 19 CU IDOL SELF LEARNING MATERIAL (SLM)

 A Wide Area Network (WAN) is a much larger network than a local area network (LAN).  A Wide Area Network (WAN) is a network that connects multiple locations over a vast geographical area via a phone line, fibre optic cable, or satellite connection.  The internet is one of the world's largest WANs.  In the fields of business, administration, and education, a network connection is commonly employed. EXAMPLES OF WIDE AREA NETWORK: Mobile broadband: in an area or country, a 4g network is commonly used. Last mile: a telecom provider connects customers' homes with fibre to deliver internet services to clients in hundreds of cities. PRIVATE NETWORK: The 44 offices are connected by a private network provided by a bank. The telecom company's telephone leased line is used to create this network. BENEFITS OF A WIDE AREA NETWORK: The following are some of the benefits of a wide area network. Geographical coverage: a wide area network covers a broad area. If our office has a branch in a distant city, we can use wan to communicate with them. We can link to another branch over the internet, which provides a leased line. Centralized data: data is centralised in a wan network. As a result, we won't have to spend money on email, files, or backup servers. Get up-to-date files: software developers operate on a live server. As a result, the programmers receive the updated files in a matter of seconds. Send and receive messages: messages are sent quickly across a wan network. You can contact with pals via web applications such as Facebook, what Sapp, and Skype. Software and resource sharing: in a wan network, we can exchange software as well as other resources such as a hard drive and ram. International commerce: we can do international commerce over the internet. High bandwidth: if we were using leased lines for our business, we will have a lot of bandwidth. The increased data transmission rate boosts our company's production as a result of the increased bandwidth. WIDE AREA NETWORK DISADVANTAGES: The following are some of the wide area network's drawbacks: 20 CU IDOL SELF LEARNING MATERIAL (SLM)

Security issue: a wan network has much more security difficulties than a lan or man network since all of the capabilities are merged, resulting in a security problem. Firewall and antivirus software are required: data is transported through the internet, which can be altered or hacked by hackers, necessitating the need of a firewall. Because some people can implant viruses into our systems, antivirus software is required to protect us. Expensive setup: the cost of setting up a wan network is significant because it necessitates the purchase of routers and switches. Identifying and resolving issues: because it affects such a vast area, resolving the issue is challenging. Two or more computer networking lans or wans, or computer network segments, are connected using devices and set by a local addressing system to form an internetwork. The term \"internetworking\" refers to this technique.  Internetworking refers to the connectivity of public, private, commercial, industrial, or governmental computer networks.  The internet protocol is used in internetworking. 1.8 INTERNETWORK TYPES 1. EXTRANET: An extranet is a telecommunication network that uses internet protocols such as tcp and transmission control protocol / internet to communicate. It is used to share data. Users with login credentials are the only ones who can access the extranet. The lowest of internetworking is an extranet. It can be classified as a man, a wan, or another type of computer network. An extranet cannot have a single lan, but it must have at least one external network connection. 2. INTRANET: An intranet is a private network that uses internet protocols such as transmission control protocol and network technology to communicate. An intranet is a website that belongs to a company and is only accessible by the company's employees or members. The intranet's primary goal is to allow employees of the company to share information and resources. The ability to operate in groups and hold teleconferences is provided by an intranet. INTRANET BENEFITS INCLUDE:  Communication: it allows for inexpensive and simple communication. An organization's employee can communicate with some other employee via email or chat. 21 CU IDOL SELF LEARNING MATERIAL (SLM)

 Timesaving: because intranet data is released in real time, it saves time.  Collaboration: collaboration is one of the intranet's most valuable features. The information is disseminated among the organization's personnel and only the authorised user has access to it.  Platform independence: the system can be connected to that other device with a different architecture, making it a neutral architecture.  Economical: people can see data and documents via a browser, and duplicate copies are sent over the intranet. As a result, the cost is reduced. 1.9WHAT IS THE DEFINITION OF TOPOLOGY? Topology refers to the network's structure and how all of the components are connected to one another. Physical and logical topologies are the two forms of topology. The geometric depiction of all the network nodes is known as physical topology. Figure 1.14 Network topologies Bus Topology  Mobile Broadband: A region or country's 4G network is extensively used.  Last mile: Customers in lots of countries are served by a telecom provider that connects their homes to the internet via fibre.  Private network: A bank has introduced up a private network that links the 44 offices together. The telecom company's leased line is used to create this network. 22 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.15 BUS Topology Wide-Area Network (WAN) Benefits: The benefits of a wide area network are as follows:  Geographic coverage: A Wide Area Network (WAN) covers a vast geographic area. If our office has a branch in another city, we can use WAN to communicate with them. We can link with another branch over the internet, which provides a leased line.  Data centralization: Data is centralised in a WAN network. As a result, we won't have to spend money on email, file storage, or backup servers.  Download updated files: Software developers operate on a live server. As a result, the revised files are delivered to the programmers in seconds.  Messages are exchanged quickly in a WAN network. Friends can be communicated with using web applications such as Facebook, WhatsApp, and Skype.  Software and resource sharing: We can exchange software as well as other resources such as a hard drive and RAM via a WAN network.  International trade: We can conduct international trade over the internet.  High bandwidth: When our organisation uses leased lines, we get a lot of capacity. Our company's productivity rises as a result of the increased data transfer rate provided by the high bandwidth. Wide-area network drawbacks include:  The Wide Area Network has the following drawbacks:  Security issue: A WAN network has much more security issues than a LAN or MAN network since all of the technologies are merged, resulting in a security issue.  Firewall and antivirus software are required since data is transported over the internet and can be altered or hacked by hackers. Because a virus can be injected into our system by a third party, antivirus software is required to protect us. 23 CU IDOL SELF LEARNING MATERIAL (SLM)

 Expensive start-up: The cost of setting up a WAN network is expensive since routers and switches must be purchased.  Identifying and resolving issues because it affects such a vast area, it is tough to resolve. Ring Topology Figure 1.16 RING Topology  A ring topology is similar to a bus topology, except that it has connected ends.  The node receiving the preceding computer's message will resends to the next node.  Data is unidirectional, meaning it only flows in one direction.  The data is continuously flowed in a single loop, which is referred to as an endless circle.  It has no terminated endpoints, i.e., each network is equipped to the next and there is no point where the network ends.  Data flows in a circular motion in a ring topology.  Token passing is the most frequent ring topology access technique.  Token passing: This is a network access mechanism that involves passing a token from one node to another.  Token: A token is a network frame that circulates.  Token passing in action  A token travels through the network, passing from one machine to the next until it reaches its destination.  The token is modified by the sender by including the address with the contents. 24 CU IDOL SELF LEARNING MATERIAL (SLM)

 Data is transmitted from one machine to the next until the target address is found to be identical. When the destination device receives the token, it sends a confirmation to the sender. A token serves as a carrier in a ring topology. Ring topology has the following advantages:  Network Management: Faulty equipment can be removed from the sample without shutting down the entire network.  Product availability: There are a variety of hardware and software components for network control and monitoring.  Price: Twisted pair cabling is affordable and widely accessible. As a result, the cost of installation is relatively minimal.  Reliable: Also, because communication system is not reliant on a particular host computer, it is a much more reliable network. Ring topology's drawbacks include:  Difficult troubleshooting: Determining cable defects necessitates the use of specialised test equipment. If there is a problem in the cable, all of the nodes' communication will be disrupted.  Network failure: When a single station fails, the entire network fails.  Network reconfiguration is difficult: Introducing additional devices to a network would cause the network to slow down.  Latency: The number of nodes has a direct relationship with the communication delay. The communication delay rises as more devices are added. Star Topology Figure 1.17 STAR Topology 25 CU IDOL SELF LEARNING MATERIAL (SLM)

 A star topology is a network configuration in which each node is integrated into a single hub, switch, or computer.  The core computer is referred to as a server, while the peripheral devices connected to it are referred to as clients.  The PCs are connected through coaxial cable or RJ-45 connections.  In a physical star architecture, hubs or switches are mostly employed as connection devices.  The star topology is the most widely used network topology. Benefits of a Star Topology  Efficient troubleshooting: When compared to a bus topology, troubleshooting in a star topology is relatively efficient. The manager of a bus topology must verify the kilometres of cable. All of the stations in a star topology are connected to the centralised network. As a result, the network administrator must troubleshoot the problem at a single station.  Network control: The star topology makes it simple to add complex network control capabilities. Any modifications to the star topology are immediately taken into account.  Limited failure: Because each station has its own connection connecting it to the central hub, a failure in one link will not affect the entire network.  Familiar technology: Because its tools are cost-effective, star topology is a well- known technology.  Easily expandable: It's simple to extend because more stations may be attached to the hub's open ports.  Economical: Star topology networks are economical because they use low-cost coaxial cable.  Fast data transfer: It has a bandwidth of about 100 Mbps. One of the most often used Star topology networks is Ethernet 100BaseT. Star topology's disadvantages  A single point of failure: If the central location or switch fails, all connected nodes will lose communication with one another.  Cable: When a large number of cable routing is required, it might be challenging to navigate. Tree topology  Tree topology incorporates the advantages of both bus and star topologies. 26 CU IDOL SELF LEARNING MATERIAL (SLM)

 A tree topology is a form of organisation in which all of the computers are linked in a hierarchical pattern. Figure 1.18TREE Topology  A root node is the top-most node in a tree topology, and all other components are children of the root node.  For data transmission, there will be only one path between two nodes. As a result, it creates a parent-child hierarchy. The Benefits of Tree Topology  Broadband transmission support: Tree topology is primarily utilised to enable broadband transmission, which means that signals are transferred over large distances without attenuation.  Expandable: The new device can be easily added to the current network. As a result, we may state that tree topology can be easily expanded.  Simple to manage: In tree topology, the entire network is divided into pieces known as star networks, which are simple to administer and maintain.  Error detection: In a tree topology, error detection and repair are simple.  Limited failure: A single station's failure does not impact the entire network.  Individual segment point-to-point wiring: It has individual segment point-to-point wiring.  Tree topology's disadvantages  Complicated troubleshooting: If a defect arises in the node, debugging the problem becomes more difficult.  Expensive: Broadband transmission devices are highly expensive.  Failure: A tree topology relies heavily on the main bus cable, and a failure in the main bus cable will cause the entire network to fail. 27 CU IDOL SELF LEARNING MATERIAL (SLM)

 Reconfiguration is tough: When new devices are introduced, reconfiguration becomes more complicated. Mesh topology Figure 1.19 MESH Topology Mesh technology is a network configuration in which machines are connected to one another via several redundant connections.  There are several ways to get from one machine to another.  It is devoid of the switch, hub, or any central server that serves as a communication hub.  The mesh topology is exemplified by the Internet.  Mesh topology is typically utilised in WAN deployments where communication breakdowns are a major concern.  Mesh topologies are primarily employed in wireless networks.  To create a mesh topology, use the formula: Number of cables = (n*(n-1))/2, where n is the number of nodes in the network. Mesh topology is classified into two types:  Mesh topology that is fully connected  Mesh topology that is partially connected 28 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.20 Types of MESH Topology Full Mesh Topology: A full mesh topology connects each computer to all other computers on the network. Partial Mesh Topology: In a partial mesh topology, just a subset of computers is connected to thosewith whom they frequently communicate. Mesh topology has the following advantages: Dependable: Mesh topology networks are particularly reliable since any link failure will not influence communication among connected computers. Fast Communication: Communication between the nodes is extremely quick. Reconfiguration is easier: Adding new devices does not affect communication between existing devices. Mesh topology's disadvantages Cost: Compared to other topologies, a mesh topology has a significant number of connected equipment, such as a router, and more transmission media. Maintenance and management: Mesh network networks are massive and challenging to maintain and administer. If the network isn't carefully monitored, a communication link loss can go undetected. Efficiency: Network efficiency is reduced due to the high number of redundant connections in this design. Hybrid Topology 29 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.21 Hybrid Topology Hybrid topology is the mixture of several different topologies. In order to transport data, a hybrid topology connects several linkages and nodes. Hybrid topology is defined as the combination of multiple different topologies, although similar topologies joined together do not lead in Hybrid topology. For example, if a ring topology exists in one ICICI bank branch and a bus topology exists in another ICICI bank branch, combining these two configurations will result in a Hybrid topology. Hybrid Topology's advantages Reliable: If a defect develops in one section of the network, the entire network will continue to function normally. Scalable: The network's size can be readily increased by adding more devices without impacting the network's functionality. Adaptable: This topology is adaptable since it can be built to meet the needs of the company. Effective: Hybrid topology is very efficient because it may be configured in a way that maximises the network's strength while minimising its weaknesses. Hybrid topology's disadvantages Complex design: The design of the Hybrid network is the main disadvantage of the Hybrid topology. The design of the Hybrid network is extremely challenging to build. Expensive Hub: Because the Hubs used throughout the Hybrid topology are distinct from the Hubs used in other topologies, they are quite expensive. 30 CU IDOL SELF LEARNING MATERIAL (SLM)

Expensive infrastructure: A hybrid network needs a lot of wiring, network equipment, and other infrastructure. 1.10MODEL OSI Open System Interconnection (OSI) is a reference model that specifies how information from one computer's software application passes through a physical media to another computer's software programme. The OSI model is made up of seven layers, each of which performs a specific network function. The International Organization for Standardization (ISO) developed the OSI model in 1984, and it is now used as an architectural paradigm for inter-computer communications. The OSI model breaks down a large task into seven smaller, more doable jobs. Each layer is given a certain task. Each layer is self-contained, allowing each layer's tasks to be completed independently. Characteristics of OSI Model: Figure 1.22 OSI Reference Model  There are two levels in the OSI model: upper levels and lower layers.  The OSI model's upper layer mostly deals with application-related difficulties, which are only implemented in software. The application layer is the one that is closest to the user. The software applications are interacted with by both the end - users and the application layer. The layer directly above another is referred to as an upper layer. 31 CU IDOL SELF LEARNING MATERIAL (SLM)

. Figure 1.23 Layers of OSI Model  The OSI model's lowest layer deals with data transmission difficulties. Hardware and software are used to implement the data link and physical layers. The physical layer is the OSI model's lowest layer, and it's the one nearest to the physical media. The physical layer is primarily in charge of putting data on the physical medium.  OSI Model Layers OSI is an acronym for Open Systems Interconnection. It was created in 1984 by ISO - the International Organization for Standardization. It is a seven-layer architecture, with each layer performing distinct functions. These seven layers work together to send data from one individual to another across the world 1. PHYSICAL LAYER (LAYER 1): 32 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.24 physical layer The physical layer is the lowest layer in the osi reference model. It is in charge of establishing a physical connection between devices. Bits of information are stored in the physical layer. It is in charge of sending individual bits through one node to another. When this layer receives data, it converts the signal received into 0s and 1s and sends them to the data link layer, which reassembles the frame. The physical layer's functions are as follows: 1. Bit synchronisation: a clock is provided by the physical layer to ensure that the bits are synchronised. This clock controls both the sender and the receiver, ensuring bit-level synchronisation. 2. Control of bit rate: the physical layer also determines the transmission rate, or the number of bits transferred each second. 3. Physical topologies: the physical layer defines the arrangement of devices/nodes in a network, such as bus, star, or mesh topologies. 4. Transmission mode: the physical layer also specifies how data is passed between the two linked devices. Simplex, half-duplex, and full-duplex transmission modes are available.  Physical layer devices include hubs, repeaters, modems, and cables.  Network layer, data link layer, and physical layer are also referred to as lower layers or Hardware Layers. 2. Data Link Layer (DLL) (Layer 2): 33 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.25 Data Link Layer The data link layer is in charge of message transport from node to node. The major purpose of this layer is to ensure that data transfers through one node to another through the physical layer are error-free. It is DLL's responsibility to transmit a packet to the Address using its MAC address when it comes on a network. The Data Link Layer is made up of two sublayers: 1. Control of Logical Links (LLC) 2. Control of media access (MAC) Depending on the sample rate of the NIC, the packet received from the Network layer is even further broken into frames (Network Interface Card). The MAC addresses of the Sender and Receiver are likewise encapsulated in the header by DLL. The MAC address of the receiver is retrieved by sending an ARP (Address Resolution Protocol) request across the wire, asking “Who owns that IP address?” and receiving the MAC address from the destination host. The data Link layer's functions are as follows: 1. Framing: The data link layer is responsible for framing. It allows a sender to deliver a set of bits to receivers that are relevant to the receiver. This can be done by attaching unique data bits to the frame's beginning and end. 2. Physical addressing: After producing frames, the Data Link Layer inserts the sender and/or receiver's physical addresses (MAC addresses) to the header of each frame. 3. Error control: The data link layer provides error control by detecting and retransmitting damaged or lost frames. 34 CU IDOL SELF LEARNING MATERIAL (SLM)

4. Flow Control: Because the data rate on both sides must be constant or the data may be corrupted, flow control coordinates the amount of data that can be transferred before acknowledgment. 5. Access control: When numerous devices share a single communication channel, the MAC sub-layer of the data link layer assists in determining which device has power over the channel at any particular time. * A frame is a packet in the Data Link layer. * The NIC (Network Interface Card) and device drivers of host PCs handle the Data Link Layer. *** Switches and Bridges are Data Link Layer devices. 3. Network Layer (Layer 3): Figure 1.26 Network Layer The network layer is responsible for data transmission between hosts on different networks. It also handles packet routing, which is the choosing of the shortest path to send a packet from a large number of options. The network layer places the IP addresses of the sender and receiver in the header. The Network layer's functions are as follows: 1. Routing: The network layer determine which path from source to destination is most appropriate. Routing is the name for this network layer function. 2. Logical Addressing: The network layer establishes an addressing system in order to uniquely identify each network device. The IP addresses of the sender and receiver are 35 CU IDOL SELF LEARNING MATERIAL (SLM)

inserted in the header by the network layer. An address like this recognises each gadget in a unique and universal way. * Packet is the name for a segment in the Network layer. ** Networking equipment such as routers implement the network layer. 4. Transport Layer (Layer 4): Figure 1.27 Transport Layer The application layer receives services from the transport layer, while the network layer receives services from the transport layer. Segments are the units of data in the transport layer. It is in charge of the full message's delivery from beginning to end. If an error is detected, the transport layer acknowledges the successful data transfer and re-transmits the data. • At the sender's end, the Transport layer takes prepared data from the top layers, performs segmentation, and implements Flow and Error Control to assure proper data delivery. In addition, it includes the Source and Destination port numbers in its header and sends the partitioned data to the Network Layer. Note that the sender must be aware of the receiver's application's port number. This target port number is usually set, either automatically or manually. When a web application sends a request to the web server): for example, it normally uses port 80, which is the default port for web applications. A default port is assigned too many programmes. • At the receiver's end, the Transport Layer scans the port number from the header and sends the data to the appropriate application. It also does data segmentation, sequencing, and reassembling. 36 CU IDOL SELF LEARNING MATERIAL (SLM)

The transport layer's functions are as follows: 1. Message Segmentation and Reassembly: This layer takes the message from the (session) layer and divides it down into smaller chunks. A header is connected with each segment that is created. The message is reassembled by the transport layer at the destination station. 2. Service Point Addressing: The transport layer header includes a form of address termed service point address or ports address in order to deliver the message to the relevant process. The transport layer ensures that the information is delivered to the relevant process by supplying this address. The transport layer provides the following services: 1. Connection-Oriented Service: This is a three-phase procedure that includes establishing a connection, establishing a connection, and establishing a connection. - Data Transfer – Disconnection / Termination After receiving a packet or series of packets, the recipient sends an acknowledgement back to the source in this form of communication. This method of transmission is secure and trustworthy. 2. Service with no connection: This is a one-step operation that includes data transfer. The receiver does not confirm receipt of a packet in this sort of transmission. This method enables for substantially faster device-to-device communication. One that is connection- oriented is more dependable than service that is not. * Data in the Transport Layer is referred to as Segments, and the Operating System is in charge of the Transport Layer. It is a component of the operating system that uses system calls to communicate with the Application Layer. The Transport Layer is referred to as the \"heart\" of the OSI model. 5. Session Layer (Layer 5): 37 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.28 Transport Layer This layer is in charge of establishing connections, maintaining sessions, authenticating users, and ensuring security. The session layer's functions are as follows: 1. Establishment, maintenance, and termination of sessions: The layer enables the two processes to create, use, and end a connection. 2. Synchronization: This module enables a process to insert checkpoints into the data that serve as synchronisation points. These synchronisation points aid in the detection of errors so that data may be correctly re-synchronized, message ends are not severed prematurely, and energy loss is avoided. 3. Dialog Controller: The session layer enables two systems to communicate in half-duplex or full-duplex mode. In the TCP/IP architecture, all three layers (including the Session Layer) are combined into a single layer called \"Application Layer.\" **These three layers are implemented by the network application directly. These are also referred to as Software Layers or Upper Layers. 6. Presentation Layer (Layer 6): 1. The Translation layer is also known as the Presentation layer. The information from either the application layer is retrieved and processed here so that it may be transmitted across the network in the proper format. 2. The presentation layer's functions are as follows: 38 CU IDOL SELF LEARNING MATERIAL (SLM)

3. ASCII to EBCDIC conversion, for example. 4. Data Encryption/Decryption: Data encryption converts data into a different format or code. The cypher text is the encrypted data, while the plain text is the decoded data. When encrypting and decrypting data, a key value is used. 5. Compression: Reduces the amount of data that must be sent over the network. Figure 1.29 Presentation Layer 7. Application Layer (Layer 7): 39 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.30Application Layer The Application layer, which is implemented by network applications, is at the very application layer of the OSI Reference Model series of layers. These programmes generate the data that must be sent across the network. This layer also acts as a window for application services to connect to the network and show the information they receive to the user. Browsers, Skype Messenger, and other applications are examples of applications. **Application Layer is also known as Desktop Layer. The Application layer has the following functions: 1. Network Virtual Terminal 2. FTAM (File Transfer Access and Management) is a programme that allows you to access and manage files. 3. Postal Services TCP/IP Suite of Protocols: The TCP/IP suite is a collection of protocols that are currently used on computer networks (most notably on the Internet). It specifies how information should be packetized, labelled, transferred, routed, and received on a TCP/IP network, providing end-to-end communication. This functionality is divided into four abstraction layers, each of which houses one of the suite's protocols. The Transmission Control Protocol (TCP) and the Internet Protocol (IP) are the two most essential protocols in the TCP/IP suite (IP). The TCP/IP suite includes the following protocols:  ARP (Address Resolution Protocol) is a protocol that links a MAC address to an IP address.  IP (Internet Protocol) is a protocol that allows packets to be delivered from a source host to a target server based on IP addresses.  ICMP (Internet Control Message Protocol) is a protocol for detecting and reporting network errors. In the game of ping, this term is used.  TCP (Transmission Control Protocol) is a connection-oriented protocol for transferring data between two computers.  UDP (User Datagram Mechanism) is a connectionless data transport protocol. There is no assurance of data delivery because a session is not established before the data transfer.  FTP (File Transfer Protocol) is a protocol for transferring files from one computer to another. 40 CU IDOL SELF LEARNING MATERIAL (SLM)

 Telnet (Telecommunications Network) is a programme that allows you to connect to a remote computer and send commands.  DNS (Domain Name System) is a system for resolving host names to IP addresses.  HTTP (Hypertext Transfer Protocol) is a protocol for transferring data (text, graphics, sound, video and other image formats) over the Internet. The following table shows which protocols reside on which layer of the TCP/IP model: Figure 1.31 Protocols of Layers 1.11SUMMARY • The OSI model is a layered method that specifies how data from a network device's application goes from the origin to destination across a physical media and then interacts with the network device's software application. • The Open Systems Interconnection (OSI) model is a seven-layer model that depicts how computer systems communicate over a network. In the early 1980s, it was the first standard model for network communications, and it was adopted by all major computer and telecommunications businesses. • The current Internet is built on the TCP/IP paradigm rather than the OSI model. The OSI 7-layer model, on the other hand, is still extensively used since it helps to see and communicate how networks work, as well as isolate and diagnose networking issues. • The way nodes in a network are connected to one another is referred to as network topology. How they communicate is determined by the network structure. It refers to the method by which computer systems or network devices are linked to one another. Both the physical and conceptual aspects of a network can be defined by topologies. In the same network, the logical and physical topologies could be the same or distinct. • To communicate, network devices must agree on a set of rules, and they must utilise the same protocol and understand each other. At various OSI layers, a large range of network protocols exist. LAN and WAN protocols, for example, are employed at the lower OSI layers. • Based on the devices and places they connect, networks can be divided into the following categories:A Local Area Network (LAN) is a limited computerised 41 CU IDOL SELF LEARNING MATERIAL (SLM)

network that allows host systems to connect and share information (e.g., papers, audio files, video files, e-mail, and chat messages) as well as a number of productivity tools. • A Wide Area Network (WAN) is a network that spans a large geographical area and is owned by an Internet Service Provider who may charge a fee for its WAN services. • IPv4 addresses were 32-bit numbers expressed as 0s and 1s strings. Because IPv6 addresses are 128 bits long, there is a greater pool of IPv6 addresses. 1.12 KEYWORD • OSI Model―Seven logical layers make up the Open System Interconnection model. • WAN- The term \"wide area network\" refers to a network that spans a significant area, such as the states of a country. • Access Point -Alternatively referred to as a base station and wireless router, an access point is a wireless receiver which enables a user to connect wirelessly to a network or the Internet. This term can refer to both Wi-Fi and Bluetooth devices. • Active Topology-The term active topology describes a network topology in which the signal is amplified at each step as it passes from one computer to the next. 1.13 LEARNING ACTIVITY 1. Analyse, what will happen, if Routing and logical addressing is not performed in Network Layer ___________________________________________________________________________ ___________________________________________________________________________ 2. Suppose your institute has 50 computer system in a lab. You are asked to set up a local network for those systems. What kind of topology you will choose and how will you configure it? Explain ___________________________________________________________________________ ___________________________________________________________________________ 1.14 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. Discuss the model of basic communication 2. What is data communication? 42 CU IDOL SELF LEARNING MATERIAL (SLM)

3. Write narrow description on computer network architecture. 4. What do you mean by Internetwork? Explain its characteristics. 5. Write about TCP/IP protocol suite. Long Questions 1. List the basic concepts of networking and explain its types in detail. 2. Explain the uses of computer network. 3. Discuss about the types of computer networks. 4. Explain about OSI model in detail 5. What is Topology? Explain its types in detail B. Multiple Choice Questions 1. LAN stands for: a. Local Area Net b. Local Area Network c. Local Array Network d. Local Array net 2. Which of the following not a topology? a. Bus b. Star c. pear to pear d. Ring 3. _____ are the set of guidelines that both the transmitter and receiver agree on. a. protocols b. computer networks c. telecommunication d. Topology 4. _____ is a collection of devices that are referred as nodes and connected through media link. 43 CU IDOL SELF LEARNING MATERIAL (SLM)

a. Devices b. Network c. Channel d. Computers 5. The time taken for a message to move from one machine to another is called _____ a. Response time b. Throughput time c. Transit time d. Total time 6. ______ is the exchange of data between different devices across a transmission media. a. Data communication b. Transfer data c. Network d. Intranet 7. ___________is a computer that is used to store data and managed by network administrator. a. Medium b. Super c. Email system d. Server 8. ______ is the ability to add new components to the network a. Scalability b. Reliability c. Performance d. Throughput 44 CU IDOL SELF LEARNING MATERIAL (SLM)

Answers 1-b, 2-c, 3-a, 4-b, 5-c, 6-a, 7-d, 8-a 1.15 REFERENCES Reference books  Behrouz A Forouzan, “Data Communications and Networking”, McGraw Hill.  Andrew S. Tanenbaum, “Computer Networks”, Pearson Education.  Subir Kumar Sarkar, T.G. Basavaraju, C. Puttaamadappa, “AdHoc Mobile Wireless Network: Principles, Protocols, and Applications, CRC Press. Textbook references  James F. Kurose, Keith W. Ross, “Computer Networking”, Pearson Education.  Michael A. Gallo, William M. Hancock, “Computer Communications and Networking Technologies”, CENGAGE Learning Websites:  https://www.techopedia.com/definition/10062/wireless-communications  https://www.computernetworkingnotes.com/  https://www.guru99.com 45 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT 2–NETWORK LAYER STRUCTURE 2.0 Learning Objectives 2.1 Introduction to IP address 2.2 Subnetting 2.3 Classless Inter -domain Routing (CIDR) 2.4 ARP 2.5 RARP 2.6 DHCP 2.7 IPV4 and IPV6 2.8 Summary 2.9 Keywords 2.10 Learning Activity 2.11 Unit End Questions 2.12 References 2.0 LEARNING OBJECTIVES After studying this unit, you will be able to:  Describe the basics of IP address  Elaborate the importance of Subnetting  State the concepts of ARP, RARP,DHCP  Describe the working of IPV4 and IPV6 2.1 INTRODUCTION TO IP ADDRESS An IP (Internet Protocol) address is a unique label given to devices linked to a computer network that communicates using the IP protocol. An IP address serves as a unique identification for a certain machine on a network. It also aids in the creation of a virtual link between a source and a destination. IP addresses are also known as IP numbers or internet addresses. It allows you to specify the addressing and packets scheme's technical format. TCP and IP are used in most networks. An IP address is made up of four numbers, each of which includes one to three digits and is separated by a single dot (.). 46 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.1 IP address There are two elements of an IP address: Prefix: The IP addresses prefix specifies the physical network under which the computer is connected. A network model can be viewed as a prefix. Suffix: The suffix component identifies the network's individual computers. The host address is also known as the suffix. An Internet protocol (internet protocol address) is a tabular value of a network interface that uniquely identifies it.IPv4 addresses are 32 bits long. There are a total of 4,294,967,296 (232) unique addresses available. IPv6 addresses are 128 bits long, allowing for a total of 3.4 x 1038 (2128) distinct addresses. Different reserved addresses as well as other factors restrict the overall useable address pool in both versions. IP addresses are integer values, but they're usually written in decimal (IPv4) or hexadecimal (IPv6) to make them easier to understand and use for people. The Internet Protocol (IP) is a set of guidelines and specifications for producing and transferring packets of data, or datagrams, between networks. The Internet Protocol (IP) is an element of the Internet protocol suite's Internet layer. IP is included in of the network layer in the OSI paradigm. IP is usually combined with a higher-level protocol, the most common of which being TCP. RFC 791 is the standard that governs the IP protocol. How IP works? IP was created to function in a dynamic network. This indicates that IP must function without the use of a centralized directory or monitors, and it cannot rely on the existence of certain links or nodes. Because IP is a connectionless, datagram-oriented protocol, each packet must include the port Number, destination IP address, as well as other data in the headers to be transmitted correctly. When these characteristics are combined, IP becomes an unstable, best-effort delivery mechanism. Upper-level protocols are in charge of error correction. TCP, which would be a connection-oriented protocol, and UDP, that is a connectionless protocol, are two of these protocols. 47 CU IDOL SELF LEARNING MATERIAL (SLM)

In an IP network, an IP address functions similarly to a postal address. A postal address, for example, is a combination of two addresses, such as your region and your home address. The address, often known as your area, is a collection of addresses for all houses in a given region. The name and address are the one-of-a-kind address for each of your residences in that neighbourhood. Your location is indicated by a PIN code number here.The network address in this case refers to all hosts that are members of a certain network. The host address is a network's unique address for a certain host.TCP/IP is the most common type of internet traffic. What is Classful Addressing? From 1981 until Classless Inter-Domain Addressing was established in 1993, classful addressing was a network designed to address the Internet's architecture. Based on four address bits, this addressing mechanism separates the IP address into five distinct groups. Classes A, B, and C provide identifiers for networks of three different sizes. Class D should only be used for multiplex and class E is reserved for testing reasons only. A Network (Class A) When there are a lot of hosts, the IP address class is employed. The first 8 bits (often known as the first octet) of a Class A network identify the network, while the next 24 bits identify the hosts into that network. 102.168.212.226 is an illustration of a Class A address. \"102\" identifies the network, whereas 168.212.226 identifies the host. 127.0.0.0 to 127.255.255.255.255.255.255.255.255.255.255.255.255.255 255.255 is allocated for loopback and diagnostics tasks and cannot be utilised. Network of Class B The binary addresses in a B class IP address begin with 10. The class decimal number of this IP address can range from 128 to 191. Loopback, used for private testing on the local computer, is assigned the number 127. The initial 16 bits (known as the two octets) aid in network identification. The remaining 16 bits are used to identify the network's host. 168.212.226.204 is an example of a Class B IP address, where *168 212* defines the network and *226.204* specifies the Hut network host. Network of Class C A Class C IP address is one that is appropriate for a small network. Three octets are being used to define the network in this type. This IP address ranges from 192 to 223. 48 CU IDOL SELF LEARNING MATERIAL (SLM)

The first two bits of the address are set to 1 as well as the third bit is set to 0, making the first 24 bits of the value they and the surviving bit the host address in this type of network address mechanism. To connect to the network, most local area networks used Class C IP addresses. An example of a Class C IP address is as follows: 192.168.178.1 Network of Class D Multicasting apps only use Class D addresses. Regular networking operations never use Class D. This class handles the first three bits of the address, which are set to \"1,\" and the fourth bit, which is set to \"0.\" 32-bit network addresses are known as Class D addresses. To identify multicast groups, all of the values inside the range are used. As a result, there is no need to separate the host address from either the IP address; hence there is no subnet mask in Class D. Class E IP addresses are defined by setting the first four network address bits to 1, allowing you to use addresses ranging from 240.0.0.0 to 255.255.255.255. The E class, on the other hand, is reserved and its use is never specified. As a result, many network implementations consider these addresses to be undefinable or unlawful. An example of a Class E IP address is as follows: 243.164.89.28 Classful IP addressing has some drawbacks. The following are the disadvantages and disadvantages of the classful Ipv6 address method:  There's a chance you'll run out of address space shortly.  Class boundaries did not promote efficient address space allocation.  The following are the rules for assigning a Network ID Because 127 is a class A address designated for internal loopback functions, the network ID cannot begin with that number. All bits of the network ID set to 1 are reserved to be used as an IP broadcast address that can be used for anything else. The network ID's bits are all set to 0. They should not be routed because they are used to identify a specific host on the local network. 2.2 SUBNETTING 49 CU IDOL SELF LEARNING MATERIAL (SLM)

The practise of subnetting is the division of a system into two or more smaller networks. It improves routing efficiency, which helps to improve network security while also shrinking the broadcast domain. High-order bits first from host are designated as network is known prefix by IP subnetting. A network is divided into smaller subnets using this strategy. It also aids in the reduction of the size of routing tables kept in routers. This strategy also allows you to rearrange and extend current IP address base. Why Use Subnetting? It allows you to get the most out of your IP addressing. IPV4's lifespan should be extended. There are a limited number of public IPV4 addresses available. IPV4 Subnetting increases overall performance by reducing communications by reducing collision and transmit traffic. You can use this method to deploy network security settings at the subnet interconnection level. IP network performance has been improved. Allows enormous geographical distances to be bridged. The subnetting procedure aids in the allocation of IP addresses, preventing large amounts of unused IP network addresses. Subnets are frequently set up physically for certain offices or teams inside a company to keep network traffic contained within that region. What is Subnet Mask? In an IP address, a subnet mask is a 32-bit address that distinguishes between both host name and a host address. A subnet mask distinguishes between the IP addresses and the host address in an IP address. They are not visible within the data packets that travel across the Internet. They contain the destination Address, which is matched with a subnet by a router. 50 CU IDOL SELF LEARNING MATERIAL (SLM)