What is Star Topology and How does it work?


What is Star Topology

Star topology is a network topology where every individual piece of a network is connected to a central node (frequently called a switch or hub). The connection of these network pieces of the central part is outwardly addressed in a structure like a star.

Star topology is otherwise called a star network

Advantages of star topology

•           Centralized management of the network, using the central PC, switch, or hub.

•           Easy to add one more PC to the network.

•           If one PC on the network fails, the remainder of the network keeps on working ordinarily

Disadvantages of star topology

•           May have a greater expense to carry out, particularly when utilizing a router or switch as the central network device.

•           The central network device decides the presentation and number of nodes the network can deal with.

•           If the central PC, hub, or switch comes up short, the whole network goes down and all PCs are detached from the network

Star topology examples

Ethernet is a genuine example of star topology. The Ethernet network is demonstrated after the star topology. Star topology utilizes Ethernet Star – 802.3 (10Base-T or 10Base-Tx) convention in information transmission

Tree Topology 

Bus Topology

Star Topology

Ring Topology

Mechanism of star topology

The central switch in this topology follows a Content Addressable Memory (CAM) table. The memory inside the switch saves the equipment locations of every associated PC. The sender’s PC sends a message to the switch. The switch checks the objective location from the memory and transfers the message towards the objective PC.

There is no memory in the hub. So when the hub is the central device, during transmission of a message the hub declares the objective location and asks the leaf hubs that have the location. This is named Address Resolution Protocol (ARP). Hub discovers the objective location through the ARP and drops the message at the objective location.

A few qualities features of the topology are referenced below

•           All links present in the network are coordinated towards the central node

•           This topology gives extraordinary versatility

•           Establishes point-to-point network connection.

•           On failure of a single cable, just the PC associated with the link gets separated from the all-out network.

•           To change the network, another PC is added to the central connection point of the hub. Similarly, to eliminate a device connection should be disengaged from the central connection point

Where Star Topology is used

Star topology is entirely utilized in Local Area Network (LAN). Practically all the network establishments like little homes and workplaces like to utilize a type of star topology. In a home network, the clients remotely associate their mobile phone, PC, tablet, savvy TV, and so forth to the switch with the goal that they can get to the web.

The bank is an astounding example of star topology. All parts of the bank ought to arrange star topology. The reason for such design is to a lockdown of one branch won’t influence the exchange of different branches. Indeed to assault on the information of one branch, the interloper needs to chip away at the central hub first.

The topology functions admirably on more modest networks. Several links are high in this topology. Contorted pair links, optical fiber, RJ-45, and coaxial links are utilized in the cabling of the network. Every single PC at the leaf hub utilizes separate contorted pair to associate with the hub or switch. The sort of network card picks the link connection for example coaxial link or an RJ-45 network link to join the PCs. On utilizing an RJ-45 connector, signing up to 1024 hubs are conceivable.

Star Network Topology works best in a more modest network. It preserves information on the crisis of network failure. The security issues of the hub or switch ought to be taken care of with much attention and consideration. Star topology is an entirely agreeable topology to plan the network.

Comparing star network topologies with other topologies

The star network topology functions admirably when workstations are conveyed haphazardly all through a building or facility. With the hub and communication plan, it is not difficult to add or eliminate workstations, as all cabling is pulled and associated with a central hub.

According to a cabling viewpoint, if the workstations are sensibly near the vertices of a curved polygon and the system requirements are unobtrusive, the ring network topology might fill the planned need at a lower cost than the star network topology. If the workstations lie almost along a straight line, the transport network topology might be ideal. In a star network, a link failure on a single communication will just influence the communication endpoint that it connects to the central PC. The wide range of various workstations will keep on working typically with the exemption that they cannot communicate with the device that dwells on the bombed talked. All in all, a star network is incredible according to this point of view, as a failure on one talked doesn’t influence correspondences of different communications that are working. Notwithstanding, the admonition is that, if the central hub were to fizzle, all communications on the star network additionally come up short. On the off chance that any workstation goes down, none of the different workstations will be influenced. Thusly, if network excess is required, a cross-section network topology might be the best choice.


Maintenance and Establishment of this network topology is costly because of the presence of a switch or hub as the central device. Truth be told, cost additionally increment because of the expansion in the number of links.

Like other network topologies, star topology has a limitation as well. Link length, accessible ports on the network are some significant constraints of the topology. Regarding such an actual issue, the star topology stretches out to different stars and winds up having just a single central switch or hub in the middle. The central device can be named as the backbone of the complete network in network phrasing. In such a plan, the message created for one system goes to its star’s middle then into the backbone (hub/switch). The backbone sends the message to the objective star’s central hub and the central one communicates it to a definitive objective PC.