Network Topologies

What is a Network Topology

A network topology is used to describe how networking devices, hosts, servers, and security appliances are all arranged within a network or organization.
Network topologies are used to help IT professionals to better understand how systems and devices are interconnected and to identify areas of improvement or where an issue may exist.

The bus topology is a very old network design.
It uses a single network cable as the backbone which allowed all host devices to connect to access the network resources.
On each end of the backbone network cable, there are terminators which are used to terminate/ground any unwanted or additional electrical signals on the wire.
When a host sends a message on the network, it is broadcast to all other hosts on the network. This causes a lot of contention on the network.
If there's a break anywhere along the backbone network cable, the entire network will be down.
This type of topology was very limited to scalability.

The ring topology is another older network design.
This topology connected host devices in a ring format, where one host was connected to another host.
Communication occurred in a single direction, where one device can transmit at a bit and the message has to be passed unto each host along the way until it arrives at its destination host.
Only one host can communicate at a time.
If one host was unavailable, the entire network will be down.

In a star network topology, all host devices are connected to a single network device such as a network switch.
If any host device wants to send a message to another host, the sender will forward the message to the switch that will the forward to the message to the destination host.
If a host on the network is not available, the network is not affected.
If the central networking device such as the network switch is down, the entire network or all connected hosts are affected.

In a mesh network topology, each device is connected to all other devices on the network.
This topology provides full redundancy since all devices are interconnected to each other.
As more devices join the network, more network connected are created and this creates issues when troubleshooting.
If an organization implements a mesh topology to interconnected all the remote offices, the cost will increase as more connections are created via the Internet Service Provider (ISP).

In a hybrid topology, it's always a combination of 2 or more different topologies which are interconnected.

In this type of topology, there's a central device which connects all other devices. Such as at the head office of an organization has the main router which is connected to each remote office router.
If one remote office wants to send a message to another remote office, the message is sent to the head office router (hub) which then forwards the message to the destination.
Each connected device to the hub is referred to as a spoke.

Back

Page updated

Google Sites

Report abuse