What is network toloplogy

What is a network topology?

What is a network?

• A computer network is a system in which multiple computers are connected to each other to share information and resources.

What is topology?

• Topology defines the structure of the network of how all the components are interconnected to each other. There are two types of topology: physical and logical topology.

What is the protocol?

• Different types of networking operating systems use different languages to control the communication process between the computers. These languages are called Network Protocols.

Network Topology and Protocol:-

• Network topology is the schematic description of a network arrangement, connecting various nodes (sender and receiver) through lines of connection.

Bus Topology:-

• Bus topology is a network type in which every computer and network device is connected to a single cable known as a backbone cable.

• Each node is either connected to the backbone cable by drop cable or directly connected to the backbone cable.

• When a node wants to send a message over the network, it puts a message over the network. All the stations available in the network will receive the message whether it has been addressed or not.

Features of bus topology:-

• The data signal is available to all computers connected to the bus.

•  It carries the address of the destination computers.

• Bus topology is good for connecting 15-20 computers.

• Each computer on the network checks the destination address as the data signal travels through the bus.

Advantage of the bus topology:-

• Bus topology cost is very low.

• Requires less cable length compared to other networks such as star topology.

• Easy to connect computer peripherals to a linear bus.

The disadvantage of the bus topology:-

• If there is a break in the main cable, the entire network will be shut down.

• If the network gets heavy traffic, a node's performance of the network falls.

• The length of the cable is limited.

• Extensive cabling:- A bus topology is quite simpler, but still it requires a lot of cabling.

Ring Topology:-

• It is called ring topology because it forms a ring as each computer is connected to the other computer, with the last one connected to the first.

• The data flows in one direction, i.e., it is unidirectional.

• The data in a ring topology flow in a clockwise direction.

Features of ring topology:-

• Ring network does not have terminated ends; thus, data signals travel in a circle.

• The computers or devices are connected in the ring using twisted pair cables, coaxial cables or topic fibres.

• The protocols used to implement ring topology are token ring and fibre distributed data interface (FDDI).

• Bit-by-bit data is transferred sequentially. It has to pass through every node of the network till the destination node.

Advantage of the ring topology:-

• It is a more reliable network because the communication system is not dependent on a single host computer.

• Adding components such as nodes will not affect the performance of the network.

• Because every computer is given equal access to the token, no one computer can monopolize the network.

• Product availability:-Many hardware and software tools for network operation and monitoring are available.

The disadvantage of the ring topology:-

• Failure of one computer on the ring affects the whole network.

• Adding or removing devices to the networks would slow down the network activity.

• It is difficult to troubleshoot because it requires special equipment to default the cable faults.

• If any one of the nodes fails, it disturbs all other networks.

Star Topology:-

• Star topology is an arrangement of the networks in which every node is connected to the central hub, switch or central computer.

• The central computer is known as a server, and the peripheral devices attached to the server are known as clients.

• It is used to connect a computer through a coaxial cable.

Features of star topology:-

• Every node has its own dedicated connection to the hub.

• Hub acts as a repeater for data flow.

• Can be used with twisted pair, optical fibre or coaxial cable.

• The data signal is transmitted from the source computer to the destination computer via the hub or switch.

Advantage of the star topology:-

• It is much easier to modify or add new computers to a star network without disturbing the rest of the network.

• Easy to manage and maintain the network because each node has a separate cable.

• It supports a high-speed data bandwidth of approximately 100Mbps.

• Cost effective as it uses inexpensive coaxial cable.

The disadvantage of the star topology:-

• If the central hub goes down, then all other connected nodes will not be able to communicate with each other.

• It requires more wires compared to the ring and bus topology because it is expensive to use.

• If the hub gets failed then all the connected nodes will not be able to communicate with each other.

Mesh Topology:-

• Mesh technology is an arrangement of the network in which computers are interconnected with each other through various redundant connections.

• There are multiple paths from one computer to another computer.

• It does not contain the switch, hub or any central computer which acts as a central point of communication.

Features of mesh topology:-

• In a mesh network topology, each of the network nodes, computer and other devices, are interconnected with one another.

• Every node not only sends its own signals but also relays data from the other nodes.

• This type of topology is very expensive as there are many redundant connections.

• The internet is an example of mesh topology.

Advantage of the mesh topology:-

• The networks are very reliable because if any link breaks, it will not affect the other connected computers.

• There is no link between point-to-points because it is secure.

• Fault is diagnosed easily.

• It is very fast communication between the nodes.

The disadvantage of the mesh topology:-

• It requires space to run the cable.

• Installation process is difficult, as each node is connected to every node.

• It requires several cables and input-output ports for communication.

• The management of mesh networks is very large and difficult to maintain and manage. If not monitored carefully, then the communication link in the networks fails.

Tree Topology:-

• Tree topology combines the characteristics of bus topology and star topology.

• A tree topology is a type of structure in which all the computers are hierarchically connected with each other hierarchical fashion.

• The topmost node in tree topology is known as a root node, and all other nodes are the descendants of the root node.

Features of tree topology:-

• It combines characteristics of linear bus and star topologies.

• It is arranged in a group of star workstations connected to a linear bus backbone cable.

• The top-level node in tree topology is known as a root node, and all other nodes are a hierarchy of the root node.

Advantage of the tree topology:-

• Point-to-point connection of each computer is connected to each part of the hub network.

• It is easy to add a computer by extending the cables to connect the computer.

• Error detection is an easy process.

• Fast expansion of nodes.

The disadvantage of the tree topology:-

• If any faults occur in the node, it is difficult to maintain.

• Requires high-cost devices for broadband transmission.

• If new or more nodes are added, then it becomes difficult to reconfigure.

• Failure in the main bus cable will damage the overall network.