Computer Networks Assignment-1

Computer Networks Assignment - 4th Semester CSIT

Posted by Ujjwal Rizz-ALL for CSIT 4th Semester, Tribhuwan University, Nepal on June 01, 2025, 07:19 PM +0545

1. Types of Computer Network (Based on Topology) with Advantages and Disadvantages

Network topology refers to the physical and logical layout of a network. Physical topology is the actual layout or geometric representation of the computers, cables, and other network devices. It describes the placement of nodes. Logical topology is how the network appears to the devices that use it.

Some common topologies include Bus, Star, Ring, Mesh, Tree, Hybrid, and Wireless.

Bus Topology

This topology uses a single trunk, wire, or backbone to which all computers on the network are connected. Devices connect to the backbone using drop lines and taps. A drop line connects a device to the main cable, and a tap is a connector that splices into or punctures the main cable. Signals weaken as they travel along the backbone, limiting the number of taps and the distance between them due to signal degradation. This topology is described as easy but outdated and not suitable for modern networks.

Advantages: Cheap and easy to implement. Requires less cable. Does not use specialized network equipment. One node failure cannot affect the entire system. Eliminates redundancy as only the backbone stretches through the facility.
Disadvantages: Network disruption occurs when computers are added or removed. A break in the cable causes system or whole system failures. Difficult to troubleshoot. Performance degrades with more devices. Fault isolation is difficult. Failure in the entire network is possible.
Best Used In: Small temporary setups.

Star Topology

In a star topology, each device has a dedicated point-to-point link to a central controller, which can be a hub or switch. Each device requires only a single cable and one link and one I/O port. Devices are not directly linked to one another; data traffic between devices goes through the hub. It is the most widely implemented and commonly used topology due to its ease of setup and fault tolerance. It is widely used in local-area networks (LANs), and high-speed LANs often utilize a star topology with a central hub. Instead of a hub, layer 1 devices (hub, repeater), layer 2 devices (Switch, bridge), or layer 3 devices (router, gateway) can be used as the central device.

Advantages: Flexible and easy to set up and modify. Robustness: Failure of one link does not affect others. Easy Fault Identification: The hub can monitor and isolate link problems. Simple Additions and Changes: Involves only connecting or disconnecting from the hub. Moderate installation cost. Easy fault isolation. Only that node is affected by failure.
Disadvantages: Expensive. Performance is based on the central device. Single Point of Failure: The entire system depends on the hub; if the hub fails, the whole network is down. Potentially More Cabling: Each node must connect to the hub, which can require more cabling than ring or bus topologies.
Best Used In: Home, Office networks.

Ring Topology

Data travels in a circular fashion from one computer to another on the network. Each device has a dedicated point-to-point connection with two adjacent devices. The signal passes in one direction, moving from device to device until it reaches its destination. Each device includes a repeater to regenerate and pass along the signal. Typically, FDDI, SONET, or Token Ring technology are used. Ring networks are most commonly wired configurations. This topology is rarely used now due to a single point of failure unless a dual ring is used.

Advantages: Cable failures are easily located, making troubleshooting easier. Ring Network installation and reconfiguration are moderately easy. No chance of data collision. Moderate installation cost.
Disadvantages: Expansion can cause network disruption. A single break in the cable can disrupt the entire network. Difficult maintenance. One failure may disrupt the entire network.
Best Used In: Specialized LANs or WANs.

Mesh Topology

Each device has a point-to-point link to every other device. Links carry traffic only between the two connected devices. Each computer connects to every other. This provides a high level of redundancy. For 'n' nodes, each node connects to 'n-1' others. Each device requires n-1 input/output ports. In duplex mode, the total links are n(n-1)/2. This topology is rarely used.

Advantages: The network can be expanded without disruption. Dedicated connections eliminate traffic problems. Robustness: one link failure doesn't affect the entire network. Security: dedicated lines prevent unauthorized access. Easy fault identification and isolation. Excellent scalability. Excellent performance. No single point of failure.
Disadvantages: Requires more LAN cable than other topologies. Complex installation and reconnection due to extensive cabling. Potential space issues for accommodating the bulk of wiring. High cost of hardware for I/O ports and cables. Wiring is very complicated. Troubleshooting a failed cable is tricky. Complex maintenance.
Best Used In: Military, telecom, financial systems. Ideal for mission-critical networks due to redundancy.

Tree Topology

Resembles a tree, with one central node (the "trunk"). Each node is connected to the central node through a single path. Often used to create large networks. It is a hierarchical star-bus combination. This topology is useful for structured organization networks.

Advantages: Can support a large number of nodes. Can be easily expanded. Highly scalable and easily reconfigured. High installation cost. Good scalability. Moderate to High performance. Easy fault isolation.
Disadvantages: Can be difficult to troubleshoot issues as each node is connected to multiple other nodes, making it hard to identify where the issue is located. Can be less reliable than star or mesh as there are more potential points of failure; if one node goes down, it can affect the entire network. Can be more expensive to implement as it requires more cabling and equipment than other topologies. High cabling requirements. Complex maintenance. Partial disruption possible upon failure.
Best Used In: Educational campuses, large buildings.

Hybrid Topology

A type of network topology where two or more different topologies are integrated or combined to lay out a network. Offers the best flexibility for large and growing networks.

Advantages: Excellent scalability. High performance. Varies installation cost (can be high).
Disadvantages: Depends on topology mix for cabling cost. Varies fault isolation. Complex maintenance. Depends on design for failure impact.
Best Used In: Enterprises with diverse requirements.

Wireless Topology

Do not require physical cabling. Particularly useful for remote access for laptop users. Eliminate cable faults and cable breaks.

Advantages: Allows for wireless remote access. Network can be expanded without disruption. No need for wired cable for local coverage.
Disadvantages: Potential Security issues associated with wireless transmission. Limited speed in comparison to other network topologies. External interference may arise.

2. Types of Computer Network (Based on Geographical Area) and Comparison

Computer networks can be categorized by their size, area, or geographical area. The types mentioned are PAN, LAN, CAN, MAN, and WAN.

PAN (Personal Area Network)

An interconnection between different devices like a smartphone, tablet, computer, and other digital devices for personal purposes like data sharing. It has a range of 10 meters. Some PANs are wired (like USB), while others are wireless (like Bluetooth), known as WPAN.

LAN (Local Area Network)

A network in a small geographical area like a room, building, or school. It connects two or more personal computers. LANs are connected by Ethernet or Wi-Fi. They are less costly, offer a faster internet connection, and provide higher security.

CAN (Campus Area Network)

A group of interconnected Local Area Networks (LANs) within a limited geographical area such as a school campus, university campus, military bases, organizational campuses, or corporate buildings. Also called a Corporate Area Network or Residential Network (ResNet) as it's used by residents of a specific campus.

MAN (Metropolitan Area Network)

A network in a city. A MAN covers a larger area by connecting LANs to a larger network of computers. Its size is larger than LANs and smaller than WANs. MANs span cities, buildings, and towns and are connected by modems and cables. They offer average internet connection.

WAN (Wide Area Network)

A network that extends over a large geographical area, such as states or countries. A WAN is quite a bigger network than a MAN. It spans a large geographical area through telephone lines, fiber optic cables, or satellite links. The internet is one of the biggest WANs in the world. WANs are widely used in business, government, and education.

Comparison of Network Types by Geographical Area

Parameter	PAN	LAN	CAN	MAN	WAN
Full Form	Personal Area Network	Local Area Network	Campus Area Network	Metropolitan Area Network	Wide Area Network
Range	1-100 meter (Max)	Upto 2KM	1-5KM	5-50KM	Above 50KM
Transmission Speed	Very High	Very High	High	Average	Low
Area	Within a room	Within office, buildings	Within university, corporate offices	Within City	Within countries
Ownership	Private	Private	Private	Private or Public	Private or Public
Maintenance	Very Easy	Easy	Moderate	Difficult	Very Difficult
Error Rate	Very low	Low	Moderate	High	Very High

3. Application Areas of Computer Networks

Major application areas of computer networks include:

Business Applications
Home Application
Mobile Computers
Healthcare and Medical Science
Education and Research
Entertainment
Research and Science
Environmental Monitoring etc.

Networks are used for File Sharing (quick and easy direct file sharing). Resource Sharing (sharing printers, fax machines, modems, scanners, hardware, software). Communication (via email, messages, message broadcast). Flexible Access (accessing files from computers throughout the network, an attempt to end the “Tyranny of geography”). Sharing of Information (sharing data over geographically large distances). Other applications/benefits include Information Sharing (easy accessibility from anywhere, search capability via WWW), Remote computing, and Distributed processing.

4. Network Architecture and Its Types

Computer Network Architecture is defined as the physical and logical design of the software, hardware, protocols, and media for data transmission. It defines how computers should connect to achieve maximum advantages like better response time, security, and scalability. Generally, there are two types: Peer-To-Peer network and Client/Server network.

Peer-to-Peer (P2P) Architecture

In a P2P network, "Peers" are computer systems connected to each other. Files can be shared directly between systems without a central server. The focus is on connectivity. Each computer acts as both a file server and a client. Once connected, P2P software allows searching for files on other clients' computers. All computers are equal peers in the network. Resources are shared directly among peers.

Advantages: Less costly as there's no central server for backup. Robust: A single computer failure doesn't affect others in the network. Installation is easy as each computer manages itself. The server is not bottlenecked as services are provided by several nodes. Easily scalable; new peers can join without central coordination.
Disadvantages: Each computer must manage its own backup and security measures separately. Scalability can be an issue as connecting each computer to every other is difficult. Less control and security, challenging to enforce access restrictions in a decentralized network. Can be less reliable; if many peers go offline, network performance suffers.

Client/Server Network (Tiered Architecture)

A network architecture where each computer or node is either a client or a server. Computers have different roles; some are clients, and some are servers. Resources are centralized on servers, and clients request them.

Server

Provides services for clients, also known as a host computer. Controls access to hardware and software on the network. Provides storage area for programs, data, and information. Provides access to stored data. Servers can be Application Server, Message Server, Proxy Server, Database Server, Web Server, etc. System administration manages data on the server.

Client

Also known as a user, computer, or end-user. Requests resources from the server. Independent from other clients. Gets files from, sends files to, deletes, copies, and renames files on the server.

Advantages: Data backup is easy and cost-effective as it's managed centrally. Performance is better due to improved response time and a more powerful server. Security is better as unauthorized access is denied by the server. Scalability is not an issue; a large number of computers can be connected. Use of a dedicated server increases the speed of sharing resources. Centralization is an advantage. More control and security with centralized access control on servers. More reliable; redundancy and backups can be managed centrally.
Disadvantages: Requires a specialized, expensive server with large memory and storage. Requires a special operating system (Network Operating system). Requires a Dedicated Network Administrator. The server may become a bottleneck. If the server fails, the whole network goes down. Complex setup; requires server configuration and network planning.

5. Protocols and OSI Model

For communication to occur, entities must agree on a protocol. A protocol is a set of rules that governs data communications. A protocol defines what is communicated, how it is communicated, and when it is communicated.

The key elements of a protocol are:

Syntax: The structure or format of the data, meaning the order in which they are presented. It indicates how to read the bits – defining field borders or boundaries. For example, a simple protocol might expect the first 8 bits for the sender's address, the next 8 for the receiver's, and the rest as the message. Syntax must be the same for both sender and receiver to communicate.
Semantics: Interprets the meaning of each section of bits. It defines how a particular pattern is interpreted and what action is taken based on that interpretation. For instance, does an address identify the route or the final destination?
Timing: Deals with when data should be sent and the speed at which data is sent or received. If a sender produces data faster than the receiver can process it, the transmission will overload the receiver, leading to data loss.

OSI Reference Model

OSI stands for Open Systems Interconnection. It was proposed by ISO (International Organization for Standards) in 1984, after the TCP/IP model. The term "Open" means "to communicate with any 2 systems". The process of breaking network functions into layers reduces complexity. It is also called OSI layered architecture or OSI Protocol architecture. Each layer provides a service to the layer above it and communicates with the same layer's software or hardware on other computers. The delivery of the package is guaranteed in the OSI Model. It is described as a theoretical/Reference Model. OSI model has separate Presentation layer and Session layer.

There are 7 layers in the OSI Reference model:

Physical Layer: The lowest layer, dealing with the actual physical transmission of data over a physical medium (copper wires, optical fibres, wireless radio waves). It defines the hardware characteristics and electrical/optical specifications. Devices at this layer include Hub, Repeater, Modem, Cables. It deals with the mechanical and electrical specifications of the interface and transmission medium. Protocols/Standards: RS232, 100BaseTX, ISDN.
Data Link Layer: Receives data from the network layer, creates frames, and adds physical addresses to these frames. The data unit is called an Ethernet frame. It's divided into two sublayers: MAC (Media Access Control) and LLC (Logical Link Control). The MAC sub-layer is responsible for data encapsulation and accessing media. Encapsulation involves adding headers (containing sender/receiver MAC addresses) and trailers (4 bytes of error checking data) to IP packets received from the network layer. Access method like CSMA/CD is part of this layer. LLC offers flow control and error control. Responsibilities: Framing, Physical Addressing, Flow control, Error control (Detecting and Retransmitting damaged or lost frames), Access control (Which device has control over the link). Protocols: PPP, Frame Relay, ATM, etc.
Network Layer: The transport layer passes TCP segments or UDP datagrams to this layer. It accepts these segments/datagrams, adds logical addressing, and forms a packet. Responsible for moving packets from source to destination across multiple links. Provides internetworking. Also determines the best path for packet delivery. Offers: Logical addressing (IP addressing), Routing (Responsible for delivering packets to the final destination), Path determination (choosing the best path, e.g., OSPF). Protocols: IPV4, IPV6, Internet Control Message Protocol (ICMP), IPSEC, ARP.
Transport Layer: Ensures process-to-process delivery of messages. Uses TCP and UDP protocols. Normally, the OSI transport layer is connection-oriented, meaning TCP is selected. UDP: Does not support segmentation, Connectionless, Unreliable, data unit is UDP datagram. TCP: Supports segmentation, Connection oriented, Reliable, data unit is TCP segment. Responsibilities: Port Addressing (specifies a specific process or service, e.g., HTTP: 80, FTP: 21, SMTP: 25), Segmentation and reassembly (messages divided into segments), flow and error control, Connection control (either connection-oriented or connectionless). Protocols: TCP, UDP.
Session Layer: Creates communication channels and controls ports and sessions. Establishes, maintains, and ends a session. Responsible for dialog control (half or full duplex) and coordinates communication between systems. Enables two systems to enter into a dialog/communication. Responsibilities: Session management, Authentication, Authorization, Synchronization (allows adding checkpoints into a data stream). Protocols: NetBIOS, PPTP (Point-to-Point Tunneling Protocol).
Presentation Layer: Responsible for translating, compressing, encrypting, and decrypting data. The data is in the form of characters or numbers. Example: Character code translation from ASCII to EBCDIC. Before transmission, it reduces the number of bits representing the original data (compression). It helps encrypt data for security. Protocols: MPEG, ASCII, SSL, TLS.
Application Layer: Allows access to network resources. This is the highest layer and is closest to the user. An application (like a browser) gets data here, and a user interacts with it. It helps identify communication partners, determines resource availability, and synchronizes communication. Allows users to log on to a remote host and provides various e-mail services. Protocols: SMTP, HTTP, FTP, POP3, SNMP, DNS etc.

6. Standardization in Computer Networking

Standards provide guidelines to manufacturers, vendors, government agencies, and other service providers. Standards ensure the kind of interconnectivity necessary in today's marketplace and international communications. They are essential in creating and maintaining an open and competitive market for equipment manufacturers.

Is standardization necessary for computer networking? Based on the sources, standards are presented as necessary. They ensure interconnectivity between diverse equipment from different manufacturers. Without standards, products from one vendor might not be able to communicate with products from another, leading to fragmented and incompatible networks. Standards also foster competition by ensuring that different vendors can produce compatible products.

The sources explain why standards are needed by stating their purpose and importance in ensuring interconnectivity and market competitiveness.

My Own View with Illustrations: Standardization is critical for seamless communication across devices and networks. For example, the Wi-Fi standard (IEEE 802.11) allows devices from different manufacturers—like a Dell laptop and a TP-Link router—to connect effortlessly. Without such standards, each manufacturer might use proprietary protocols, making it impossible for devices to communicate, leading to isolated systems.

How it helps for Globalization: Standardization in computer networking supports globalization by ensuring global compatibility and communication. For instance, the TCP/IP protocol suite, a global standard, enables the internet to function worldwide, allowing a user in Nepal to access a website hosted in the USA seamlessly. This fosters global collaboration, trade, and information sharing.

Types of Standards:

De facto: Standards adopted through widespread use, not approved by an organized body. Often established by manufacturers introducing new products. Example: Ethernet became a de facto standard due to its widespread adoption.
De jure: Standards legislated by an officially recognized body. These are standards recognized officially by an Organization.

Some Standards Organizations:

International Organization for Standardization (ISO)
International Telecommunication Union-Telecommunication Standards Sector (ITU-T)
American National Standards Institute (ANSI)
Institute of Electrical and Electronics Engineers (IEEE)
Electronic Industries Association (EIA)

7. Connection-Oriented vs. Connectionless Services

A "connection" often refers to a link or bond between two or more things/devices, such as internet connections or links between machine parts.

Connection-Oriented Service

Before communication begins in a connection-oriented service, the user follows a sequence of operations:

Connection is established (Virtual Connection).
Data/Information Sent.
Connection Release.

Connection-oriented service is described as more reliable than connectionless services. A common example is TCP (Transmission Control Protocols). Connection-oriented services may be implemented using Circuit-switched connections, which are dedicated communication paths established between two endpoints for the duration of a session, ensuring constant, guaranteed bandwidth and connection quality. Connection is established through a process of signalling (like Three step handshaking). Packet travel is sequential. There is more delay due to the acknowledgement process. It is suitable for long and steady communication. Resource needs to be allocated. Congestion is not possible. It is possible to retransmit lost data bits.

Connectionless Service

It is similar to postal services, as each message carries the full address of the destination. Each message is routed independently from source to destination. The order of messages sent can differ from the order received. Data is transferred in one direction without checking if the destination is still there or prepared to accept the message. Authentication is not needed. Packets are sent from one party to another with no need for connection establishment or release. The packets are not numbered; they may be delayed, lost, or arrive out of sequence. There is no acknowledgment. A common example is UDP services. No prior connection is established. No prior allocation of resources is required. Less reliable. Congestion can occur likely. It can be implemented using Packet Switching. Retransmission is not possible. Suitable for bursty transmissions. There is no concept of signalling. Packet travel is random. No delay due to the absence of a connection established phase.

8. TCP/IP Model

TCP/IP Model: The TCP/IP protocol suite was developed before the OSI model. It is a set of protocols developed to allow cooperating computers to share resources across a network. In 1969, DARPA funded a project for an experimental packet switching network called ARPANET. In 1975, ARPANET became operational. TCP/IP protocols were adopted as Military Standards (MIL STD) in 1983, requiring all hosts to convert to them. In 1983, ARPANET was divided into MILNET and a smaller ARPANET, and "The Internet" referred to the entire network (MILNET and ARPANET).

The TCP/IP model is a widely used networking model consisting of four layers: Application, Transport, Internet, and Link (Network Access Layer). It serves as the foundation for the modern internet. Key protocols include TCP and IP. It is a more flexible and adaptable model compared to OSI. It is described as a Practical/Implementation Model. Delivery of the package is not guaranteed in TCP/IP Model. It follows a Horizontal approach, where the Transport layer on one device communicates directly with the Transport layer on another device to ensure end-to-end data delivery. It is described as more reliable than the OSI Model. It was developed by the DoD (Department of Defense). TCP/IP model does not have separate Presentation layer and Session layer.

The four layers of the TCP/IP Model and their PDUs (Protocol data units) are:

Application Layer: Provides network services directly to end-users or applications. Includes protocols like HTTP, SMTP, FTP. Facilitates communication between software applications. PDU: Application message. Protocols: HTTP, SMTP, FTP, DNS (These are mentioned as examples in the text, not a full list by layer). The OSI layer 7 protocols list includes SMTP, HTTP, FTP, POP3, SNMP, DNS, which are commonly associated with the TCP/IP application layer as well.
Transport Layer: Responsible for end-to-end communication and data flow control between devices on different networks. Includes TCP and UDP. TCP provides reliable, connection-oriented communication. UDP offers connectionless, unreliable communication. PDU: TCP segment/UDP datagram. Protocols: TCP, UDP.
Internet Layer: Handles logical addressing, routing, and forwarding of data packets across different networks. Primary protocol is IP, which enables routing based on IP addresses. PDU: IP packet. Protocols: IP (Internet Protocol). The OSI layer 3 protocols list includes IPV4, IPV6, ICMP, IPSEC, ARP, which are also associated with the TCP/IP Internet layer.
Link Layer / Network Access Layer: Deals with the physical connection between devices on the same local network segment. Includes hardware-specific protocols and technologies like Ethernet, Wi-Fi. Responsible for addressing and error detection at the local network level. PDU: Ethernet Frame. Protocols: Ethernet, Wi-Fi (These are mentioned as technologies/examples, not a full list). The OSI layer 2 protocols list includes PPP, Frame Relay, ATM, etc., and layer 1 lists RS232, 100BaseTX, ISDN, which could be relevant to the combined Link layer.

Comparison of TCP/IP Model with OSI Reference Model

Aspect	OSI (Open Systems Interconnection)	TCP/IP (Transmission Control Protocol/Internet Protocol)
Full Form	Open Systems Interconnection	Transmission Control Protocol/Internet Protocol
Layers	7 layers	4 layers
Usage	Low usage, Generally in Research	Mostly used for network design
Model	Theoretical/Reference Model	Practical/Implementation Model
Delivery Guarantee	Guaranteed	Not guaranteed
Approach	Follows vertical approach	Follows Horizontal approach
Reliability	Less reliable than TCP/IP Model	More reliable than OSI Model
Developed By	ISO (International Organization for Stds.)	DoD (Department of Defense)
Protocol Replacement	Protocols are hidden, easily replaced	Replacing protocols is not easy
Layer Separation	Separate Presentation and Session layers	Does not have separate Presentation and Session layers

9. Critiques of OSI and TCP/IP Models

The comparison table highlights differences and where one model might be considered less reliable or where protocol replacement is difficult:

OSI: Less reliable than TCP/IP Model, complex with 7 layers, limited practical use as it's mostly theoretical and used in research.

TCP/IP: Replacing protocols is not easy, delivery of the package is not guaranteed, does not have separate Presentation and Session layers which can make it less structured for certain applications.

10. Internet, ISPs, and Backbone of Network

Internet

The internet is a global network of interconnected computers and computer networks. It is the most known network of networks. The internet offers Global Connectivity, connecting millions of devices worldwide. It has a Decentralized Structure, meaning there is no central control or single point of failure; information is distributed across many servers and networks. The Internet relies on standardized protocols (e.g., TCP/IP) and open standards for compatibility and seamless communication. It provides diverse services like web browsing, email, file sharing, and social networking. Users connect through Internet Service Providers (ISPs) using technologies like broadband, wireless, or dial-up. The internet is one of the biggest WANs in the world.

ISPs (Internet Service Providers)

An Internet Service Provider (ISP) is a company or organization that provides users with access to the Internet. They may be organized as commercial, community-owned, non-profit, or privately owned entities. Internet services typically provided by ISPs include Internet access, Internet transit (providing access to the broader internet to customers or other ISPs), domain name registration, and web hosting.

Tier-Architecture of ISPs

The terms "Tier 1," "Tier 2," and "Tier 3" describe different levels of Internet connectivity and network infrastructure based on hierarchy and scope.

Tier 1 ISPs: The top level in the ISP hierarchy. They have a global network infrastructure covering multiple continents and regions. They are the backbone of the internet, providing high-speed connectivity globally. They handle large volumes of traffic and are crucial for the internet's stability and performance. Examples include AT&T, Verizon.
Tier 2 ISPs: Operate at a regional or national level, covering a specific geographic area or country. They act as regional providers, connecting end-users, businesses, and other networks to the broader internet. They may serve as intermediaries between Tier 1 ISPs and smaller, local ISPs. Examples include Cogent Communications, Zayo Group.
Tier 3 ISPs: Typically smaller, operating at a local or community level. They may connect to larger ISPs or Tier 2 ISPs to access the global internet. They are often the last-mile providers, delivering internet connectivity directly to end-users' homes or businesses. They play a crucial role in providing local access to smaller communities.

Other Types of ISP: Hosting ISPs, Mobile Box ISPs, Transit ISPs, Virtual ISPs, Free ISPs, and Wireless ISPs.

Backbone Network

Often referred to as a core network. It is a high-capacity infrastructure serving as the primary pathway for data transmission between different network segments and major locations within a network. It forms the central and essential part of a telecommunications or computer network, providing a robust and efficient means of interconnecting various subnetworks. A Backbone LAN serves as a high-capacity interconnection between individual LANs in different buildings or departments, handling aggregated traffic and facilitating efficient communication.

Types of Backbone

The backbone itself is a LAN using a LAN protocol like Ethernet, where each connection is another LAN. Commonly used architectures are Bus backbone, Star backbone, and Interconnecting a remote LAN.

Bus backbone: Uses bus topology for the backbone. Normally used as a distribution backbone to connect different buildings in an organization.
Star backbone: Uses star topology. Sometimes called a switched backbone. The backbone is just one switch that connects the LANs. The switch acts as the backbone and connects LANs simultaneously.
Interconnecting a remote LAN: Connections are established through remote bridges that link LANs via point-to-point network links.