Computer network
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This document defines and compares different types of computer network topologies. It begins by defining a computer network and its basic elements, including transmitters, receivers, hardware, communication software and protocols. It then discusses different network topologies - bus, star, ring, mesh and tree - outlining their key characteristics, advantages and disadvantages. A computer network allows interconnected computers to share resources and data, providing benefits like resource sharing, reliability, cost savings, scalability and increased productivity, but also poses risks like crashes and threats to data security and privacy.
Computer network
- 2. Definition A network is a group of interconnected computers. They share resources such as electronic mail, bulletin boards, and access to unique database. They can be thought of as information highways for data.
- 3. Data Communication System E L E M E N T S Transmitter Transmission Medium Receivers Hardware Communication Network Communication software Data Communication provider Communication protocol
- 4. Network Topology The term topology in the context of communication’s network refers to the way in which the end points or the stations of the networks are linked together. It determines the path that may be used between any pair of station of the network.
- 5. Types of Topologies Bus Topology Star Topology Ring Topology Mesh Topology Tree Topology
- 6. Bus Topology . In bus topology network, a single coaxial cable acts as a backbone to link all the devices in the networks. This topology uses the least amount of cabling and is therefore the least expensive and the simplest topology for small networks. In this network, a 50 ohms terminator terminates both ends of the network A bus topology consists of a single central cable to which all computers and other devices connect. A bus topology is also known as a bus network.
- 7. Bus Topology Advantages Disadvantages Help to reducing the number of physical line. Addition of new computer to the network is easy. All computer in the network must have good communication and decision making capability If the communication line fails the whole system breaks down.
- 8. Ring Topology In Ring topology network , all the computers are connected in closed loop. Each computer on the ring topology network acts as a repeater. It transmit data by passing a token around the network. If the token is free , a computer waiting to send data takes it, attaches the data and the destination’s address to the token , and send it . When the token reaches its destination computer, the data is removed.
- 9. Ring Topology Advantages Disadvantages This network works well where there is no central-site computer system If a link between any two computers breaks down, or if one of the computers breaks down , alternate routing is possible. The ring network requires more complicates control software than star network. if one computer fails, the entire network will go down.
- 10. Star topology Star topology is the most popular topology used for networks. In this, each computer is connected to a central device (hub), through an UTP wire. Signals from the sending computer go to the hub and are then transmitted to all the computers in a network. Since each workstation has a separate connection to the hub, it is easy to troubleshoot .
- 11. Star Topology Advantages Disadvantages Star topology has minimal line cost because only n-1 lines are required for connecting n nodes. If any of the local computers fails, the remaining portion of the network is unaffected. The system crucially depends on central node. If the host computer fails the entire network fails. If traffic between the workstations is high , an undue burden is places on the central node.
- 12. Mesh Topology A mesh topology all the devices in a network are connected to each other with many redundant connection. It provide multiple path for data traveling on the network to reach its destination. Mesh topology also provides redundancy in the network.
- 13. Mesh topology Advantages Disadvantages This type of network is very reliable, as any link breakdown will affect only communication between the connected computers. Communication is very fast between any two nodes. It is the most expensive network from the point of view of link cost . if there are N nodes in the network, n(n-1)/2 links are required. Hence, the cost of linking the system grows with the square of the number of nodes.
- 14. Tree Topology Tree is a network topology containing zero or more nodes that are linked together in a hierarchical fashion. The topmost node is called root. The root may have zero or more child nodes , connected by edges ; the root is the parent node to its children. Each child nod can in turn have zero or more children of its own. Nodes sharing the same parents are called siblings.
- 15. Tree Topology Advantages Disadvantages Point-to point wiring for individual segments. Supported by several hardware and software companies. If the backbone line breaks, the entire segment goes down. More difficult to configure and wire than other topologies.
- 16. Computer Networks A D V A N T A G E S Resource Sharing High Reliability Saving Money Scalability Communication Medium Increased Productivity
- 17. Computer Network D I S A D V A N T A G E S Crashes Data Security Privacy
- 18. THANK YOU