Network Topologies - Bus Ring Star Tree Mesh Hybrid - MyCSTutorial- The path to Success in Exam

Computer Network – Introduction, Data Communication, Needs of Computer Networks, Advantages & Disadvantages of Network, Network Terminology, Node, Workstation, Server, Types of Server, Dedicated and Non-Dedicated Server, NIC, MAC Address, and IP Address
Types of network: LAN, MAN, WAN, PAN, LAN vs WAN
Networking Devices: Modem, Hub, Repeater, Switch, Bridge, Gateway

Network Topology

Network topologies describe the ways in which the elements of a network are mapped or interconnected. They describe the physical and logical arrangement of the network nodes.

Types of Topology

Point to Point
Bus
Ring
Star
Tree
Mesh
Hybrid

Point-to-Point Topology

In Point–to–Point, two nodes are directly interconnected. In the P-P link, each node receives exactly from one node and transmits to each node directly.

Bus Topology

The bus topology uses a common single cable to connect all the workstations. Each computer performs its task of sending messages without the help of the central server. However, only one workstation can transmit a message at a particular time in the bus topology.

The transmission from any station travels the length of the bus in both directions and can be received by all other stations.

The bus has terminators at either end which absorb the signal, removing it from the bus. Data is transmitted in small blocks with destination addresses, known as packets.

Advantages of Bus Topology

Easy to connect and install.
Involves a low cost of installation time.
Can be easily extended.

Disadvantages of Computer Network

The entire network shuts down if there is a failure in the central cable.
Only a single message can travel at a particular time.
Difficult to troubleshoot an error.

Ring Topology

Nodes / Workstations – The term nodes refer to the computers that are attached to a network and are seeking to share the resources.

Data is accepted from one of the neighboring nodes and is transmitted onwards to another. Thus data travels in one direction only, from node to node around the ring. After passing through each node, it returns to the sending node, which removes it.

Advantages of Ring Topology

Short cable length.
The data being transmitted between two nodes passes through all the intermediate nodes, so no amplifier is required.
A central server is not required for the management of this topology.
No wiring closet space is required.

Disadvantages of Ring Topology

Node failure causes network failure.
Difficult to diagnose faults.
Network reconfiguration is difficult. The movement or changes made to network nodes affects the performance of the entire network.

Star Topology

Star topology is based on a central node that acts as a hub. It consists of a central node to which all other nodes are connected by a single path.

The most common example of this is 10Base-T Ethernet network installations. Each node is connected to a 10Base-T hub by means of a twisted pair cable.

Advantages of Star Topology

Due to its centralized nature, the topology offers the simplicity of operation.
It also achieves isolation of each device in the network i.e. one device per connection.
Simple access protocols.

Disadvantages of Star Topology

Failure of the central hub leads to the failure of the entire network, i.e. central hub dependency.
Long cable length.
Difficult to expand.

Tree Topology

In a tree topology, stations are attached to a shared transmission medium. It is a variation of bus topology. The shape of the network is an inverted Tree. The tree topology combines the characteristics of the linear bus and the star topology. It consists of groups of star–configured workstations connected to a bus backbone cable.

Advantages of Tree Topology

Eliminates network congestion.
The network can be easily extended.
Faulty nodes can easily be isolated from the rest of the network

Disadvantages of Tree Topology

Uses a large cable length.
Requires a large number of hardware components and hence is expensive.
Installation and reconfiguration are very difficult.

Mesh Topology

Mesh topology is a group of nodes that are all connected to each other and many types of connections are possible in a mesh topology.

There are two types of Mesh topology.

(a) full mesh topology (b) partially-connected mesh topology

In Full mesh topology, every node is connected with other nodes. There are n(n-1)/2 connections. (b) partially-connected mesh topology

In a partially-connected mesh topology, at least two of the computers in the network have connections to multiple other computers in that network. If one of the primary computers or connections in the network fails, the rest of the network continues to operate normally.

Advantages of Mesh Topology

Manages high amounts of traffic, because multiple devices can transmit data simultaneously.
A failure of one device does not cause a break in the network or transmission of data.
Adding additional devices does not disrupt data transmission between other devices.

Disadvantages of Mesh Topology

The cost to implement is higher than other network topologies, making it a less desirable option.
Building and maintaining the topology is difficult and time-consuming.
The chance of redundant connections is high, which adds to the high costs and potential for reduced efficiency.

Hybrid Topology

Hybrid topology is a mixture of two or more topologies in a way that the resulting network does not exhibit one of the standard topologies (e.g., star, bus, ring, etc.)

Advantages of Hybrid Topology