What are layers in networking?
Layers in networking pertain to individual functions or task levels in the entire course of communication between different nodes of a network.
Why do we need layers in networking?
Layers are required to break down the complexity of the system into smaller individual tasks. In other words, layering provides abstraction for all networking technologies. Each layer adds to the functionality provided by the lower layer and delivers to the higher layer, with the lowest layer dealing with physical transmission of bits and bytes, while the highest layer deals with presentation of information in an application. As such, layers provide a level of modularity, allowing each layer to work independently. No layer is dependent on how the other layers function, and so it is free to use any optimisation techniques and structures without having to modify the other layers. Each layer consist of the service it provides, the protocol it uses, and the interfaces that help the layer interact with other layers. A protocol stack is the set of particular protocols used at each layer. There are many different protocols available for each layer, each of them serving some different use cases, and using different implementations and optimisation techniques. With layering, we can decide which protocols are most suitable at each layer of communication.
Alternatively, a system with no layers can become very complex to maintain and expensive to make even slight modifications, as this would require modification of the entire stack.
There are two types of models in networking -
The OSI Model is widely appreciated as the standard of layer models, but since it's implementation is not complete, TCP/IP model is used.
Sunday, 18 September 2016
