Describe Issues for network layer :
1)Addressing :
*Specify a specific destination
2) Data transfer :
*Data only travel in one direction
*In other data can go both nays
3) Error Control :
*Here Physical communication circuits are not perfect.
*many error detecting and error connecting codes are known but data ends of tree connection must agree on which one is used.
4) Flow Control :
*Of every level is try how to trees a fast sender frame swamping a slow receiver with data.
*Some involves tinds of feedback from receiver to tree sender either directly or indirectly about tree receiver current situation.
*Other, tree sender agreed on transmission, this process is flow control
5) Multiplexing and Demultiplexing :
*When it is expensive to set up a separate connection for each pair of communicating, process tree underlying layer may deside to use tree same connection for multiple and demultiple.
6) Routing :
*When tree are multiple data between source and destination a route must be choose.
*Sometimes tree decission must be split over two or move layers.