Hybrid topology is a combination of two or more computer network topologies. For example a hybrid of star and bus topology is called tree topology. Tree topology is an example of hybrid topology.
Use of Hybrid Topology
Hybrid topology is used to get the benefits of more than one topology. For example a star topology is a very good topology that is commonly used and has so many advantages, however it cannot be used for larger networks.
On the other hand, bus topology can be used for larger networks but it lacks the advantages of star topology. By combining these two topologies, we can get the advantages of both star and bus topology, this is what is done in tree topology and this is why tree topology is preferred for larger computer networks.
Types of Hybrid topology
There are mainly three types of hybrid topologies:
1. Star ring hybrid topology
In this type of hybrid topology, star network topology and ring network topology are combined together. As shown in the star-ring topology diagram below, the central device (hub or switch) are connected in a circular manner forming a ring shape. These hubs are also having device connected to them forming a star network.
In simple words you can describe it as a multiple star networks joined in a ring network.
2. Star bus hybrid topology
In this type, star network topology and bus network topology are combined together. As shown in the star-bus topology diagram below, the hubs of star networks are connected to the backbone cable of bus topology.
3. Hierarchical Network topology
A hierarchical network topology is a type of hybrid topology, in which a node is connected to multiple nodes present at the lower level of the hierarchy. The top parent node is called root node, a node that has a parent is called child node, nodes that do not have child nodes are called leaf nodes.
Advantages of Hybrid topology
- Multiple topologies benefits: Can get the benefits of more than one topologies by joining them.
- Flexible: It is flexible as this topology can be designed as per the requirements.
- Scalable: Adding new nodes to the hybrid topology is easy.
- Large Networks: This topology is suitable for large networks.
- High Traffic: This topology can handle high amount of traffic.
- Reliable: It is more reliable than other topologies. For example in a star-bus hybrid topology, even if a switch fails, the other star networks are continue to function properly using bus line, the faulty switch can be replaced without affecting other devices on the network.
- Troubleshooting is easy: It is easy to detect fault in this topology and troubleshoot the issue. This is possible because multiple small networks made up the entire hybrid network. If a fault occurs, it can be isolated to the particular segment of network and the resolved.
Disadvantages of Hybrid topology
- Costly: Setup of hybrid topology is expensive, thus it is not suitable for small networks.
- Implementation is complex: Due to the combination of multiple topologies, the design becomes complex and it is difficult to implement it.
- More hardware requirements: It requires more hardware and software compared to other topologies. For example, a star-bus hybrid topology requires both star topology and bus topology hardware and softwares.