When each device is connected to a central hub, it is known as the star topology, in which all the devices are connected to a central device and look like a star connection. It is the most popular, likely to use network topology, and one of the most pervasive computer network configurations. In star topology, the devices do not have a direct connection with each other, nor can they establish one; rather, the devices can be connected through a hub. A switch can also be used as the central device in star topology in place of a hub. The central device in star topology works as a server, and the devices connected with it work as clients. According to the network card installed in each device, the coaxial cable or RJ-45 is the most suitable and usual in the star topology. The patch cable can also be helpful in connecting clients, servers, and other networks with the hub.
Table of Contents
- More about Star Topology
- Working of Star Topology
- Application of Star Topology
- Characteristics of Star Topology
- Advantages of Star Topology
- Disadvantages of Star Topology
More about Star Topology
Nowadays, many institutes, airports, hospitals, and banks are places where you can easily find star topology as the most commonly used network connection. In star topology, each device in the network completely depends on the central hub, i.e. if the hub fails, the whole network fails.
Now let’s understand star topology with a diagram:
The above image can give you a clear idea about the star topology network. As shown here, we have a central device that works as a server through which all the other devices are connected and work as clients. Each device in the image has a point-to-point connection with the central device, i.e. the hub or a switch, but they do not have any direct connection with each other. Thus, before reaching the final device, i.e. the destination, the message has to pass through the hub.
The star topology can also be implemented by a wireless router, ethernet/cabled structures, and other components. The star topology can be categorised as active or passive. When the outer nodes connect to a single central hub and process all the data in the network, then it is an active star. When the outer nodes connect to a single central hub and do not process any data, then it is a passive star topology.
Working of Star Topology
Star topology is very easy to understand and implement. It does not allow for establishing a direct connection between the nodes; rather, the nodes can only communicate with each other through the central device, i.e. a hub. This central device is responsible for the whole data to travel and be delivered to the destination in the network. Star topology has different ways to work in different situations. Thus, it has three categories as per the working mechanism. These categories are:
- Active Star Topology: Active star topology contains an active hub that is responsible for establishing proper communication by passing the signals to the devices. It also regenerates the communication signals if it is lost and broadcasts them to all the nodes. The feature of regenerating the signals strengthens communication amongst the devices in the network. If you have a larger number of nodes to be connected with a long cable length, then an active hub is the best choice.
- Passive Star Topology: A passive star topology uses a passive central device. Such devices can receive signals from the sender and send them to other stations. Thus a passive hub can pass the signals without any interruption but cannot regenerate or reprocess them. So, if you ever design the network using a passive hub, then it will get the data from the sender and broadcast it to all the other nodes. Once the nodes receive the data, they check for the destination address. If the address matches, the data reaches the correct destination, and if the address does not match, it discards the data. Therefore, such kinds of networks are not at all suitable for larger-size and long-distance networks.
- Star Topology with Switch: As the name suggests, it is a star topology designed by using a switch instead of a hub, and such networks are also known as the switcher star network topology. In such networks, a switch is used as a central device that serves the nodes attached to it. It can transmit the data and perform multiple functions like routing, network management, bridging, etc., but can’t transmit communication signals.
Application of Star Topology
Star topology is the most convenient and easy to implement. Thus, it can be easily seen around. Let’s see some sectors where star topology is commonly used:
o Nowadays, many institutes use star topology as they need to connect several nodes to be connected in a lab.
o Banking is one of the sectors where this topology is used through which the users can stay connected.
o The home networks are also designed in the star topology.
Characteristics of Star Topology
The characteristics of star topology are as follows:
o In star topology, the whole network doesn’t affect if we remove or connect any device.
o It is easy to install and suitable for any size of the network.
o It doesn’t have any dependency, as it is connected to multiple and individual cables.
o The chances of data loss are less in a star topology.
o The daisy chain arrangement can be used to extend the entire network.
Advantages of Star Topology
o The star topology comes up with a great advantage of fault tolerance. As all the devices in the network are connected with an individual cable, there is no chance of network failure when any node fails.
o Star topology offers scalability. When you want to add a new node to the network, you just need to have a separate cable to attach the new device.
o As all the devices are connected through the individual cables with the central device, there are very less chances of data collision.
Disadvantages of Star Topology
o The biggest disadvantage with star topology is that if the central device gets any issue, the whole network gets affected or fails.
o Star topology is expensive, as it requires a large number of cables or sometimes more switches or other devices for proper network connection.
