Optical networks are the communication network systems that make use of light signals in order to transmit data. Light signals are transmitted through optical fiber cables and message can travel at the speed of light and most of the communication processes that require high speed and reliable transmission are being switched to optical networks. There are different types of optical networks, however the basic principles are the same for all of them.
BUS TYPE OF OPTICAL NETWORK
In a bus types of optical network, all the communicating systems or computers are directly connected to a common communication line and is also called as a daisy-chain topology. In this type of optical network, a computer can talk to the main computer only when the line is free, which means that the computers have to wait for other computers to finish their communication. The disadvantage of this type of optical network is that the failure in the main line will result in the failure of entire system.
STAR TYPE OF OPTICAL NETWORK
In star types of optical network, a main computer or a hub will control the network traffic. All the client computers should communicate with the main computer or central hub which in turn passes on the message to the destination computer and vice versa.
One advantage of star topology over bus topology is that, the failure in a node will not affect the working of the entire network system. However, a failure in the central hub can result in the stopping of entire network functions.
RING TYPE OF OPTICAL NETWORK
Ring types of optical network system is very similar to that of a bus topology system except that the ring types do not have a main computer and a terminating computer. In this type of network, each computer is connected to the adjacent computers and the message to be communicated is passed on to the adjacent computer with a toke attached to the message. The token will contain the address of destination computer and each computer that receives the message will check if the message is assigned to them.
The main disadvantages of ring type of optical networks are that, there is no privacy and also a failure in one node can bring the entire system to halt.
TREE TYPE OF OPTICAL NETWORK
Tree types of optical network is an advanced version of hub network. In this type of network, several computers will be connected to central hubs that are again connected to a root hub. The main advantage of tree topology is that failures in individual nodes will not affect the entire system and the chances of failure for root hub is very less.
Even though there are different types of optical network systems, all of them works on the same basic principles such as: information can be passed to, shared, bypassed and sent to. All these principles are implemented in different ways in each type of optical network in order to achieve an efficient and reliable network communication.