TOPOLOGY

Network topology is the arrangement of the various elements (links,nodes,etc.) of a network. It is the topological structure of a network.

      Bus

Star

Ring or circular

Mesh

Tree

Hybrid

Bus topology:

Bus Topology is the simplest of network topologies. In this type of topology, all the nodes (computers as well as servers) are connected to the single cable (called bus), by the help of interface connectors. This central cable is the backbone of the network and is known as Bus (thus the name). Every workstation communicates with the other device through this Bus. 

Bus Topology is the simplest of network topologies. In this type of topology, all the nodes (computers as well as servers) are connected to the single cable (called bus), by the help of interface connectors. This central cable is the backbone of the network and is known as Bus (thus the name). Every workstation communicates with the other device through this Bus. 

Advantages of Bus Topology:

  Easy to install and configure

 Cable length required for this topology is the least compared to other networks.

  Bus topology costs very less.

  Linear Bus network is mostly used in small networks. Good for LAN.

  Failure of one node does not affect the rest of the bus network.

Disadvantages of Bus Topology :

  If the bus cable fails then the whole network will fail.

  Performance of the network slows down rapidly with more nodes or heavy network traffic.

  The bus cable has a limited length and must be terminated properly at both ends to prevent                   reflected signals.

  Slower than a ring network as data cannot be transmitted while the bus is in use by other nodes.

Star topology:

   In this type of network, a central computer (server) usually forms the main node and the subsidiary nodes are connected to it and to each other through a switch or hub.

.

Advantages:

 It is very easy to install and manage the star network topology, as it is the simplest of the lot                when it comes to functionality.

 It is easy to troubleshoot this network type, as all computers are dependent on the central hub              which invariably means that any problem which leaves the network inoperable can be traced                to the central hub.

 In star network topology, data packets don't have to make their way through various nodes.                  The fact that there is no data collision adds to its performance by making data transfer                          considerably fast.
  Also, the fact that data packets only make it through three different points ensures that the                   data is safe.
  As the nodes are not connected to each other, any problem in one particular node doesn't                     hamper the performance of other nodes in the network.

  Adding new machines or replacing the old ones is easy in this network topology, as                             disruption of the entire network is not required to facilitate the same.

Disadvantages:

 The foremost problem with the star network topology is the fact that it is highly dependent on              the functioning of the central hub.
 The size of the network is dependent on how many connections can be made to the hub. As the            number of connections increases, so does the size, and thus, the infrastructure.

 If you opt for the star topology, you will require more cable than what you would if you opt for         the linear bus topology. So, the expenses incurred on the former will also be relatively high.

The performance of the entire network is directly dependent on the performance of the hub. If             the server is slow, it will cause the entire network to slow down.

If one of the nodes utilizes a significant portion of the central hub's processing capability, it will           reflect on the performance of other nodes.
 If the central hub is compromised, it will leave the entire network vulnerable.
Ring topology:

In a ring topology, the nodes are connected in a ring and data travels in one direction using a control signal called a 'token'

Advantages of Ring Topology :

 Adding additional nodes is easy.

  All computers have equal access on network.

Disadvantages of Ring Topology :

 Difficult to configure

 If Cable breaks, then whole Network will goes down.

 If any link goes down, then network will also goes down.

 Only one medium for Data Transmission so Transmission Speed is very slow.