Question

A system has n layer protocol hierarchy. application generates massage of length m bytes. at each of the layers an h byte header is added. examine fraction of the network band width is field with header?

Answer 1

Fraction of the network bandwidth is filled with headers:

From the given data, a system contains n-layers protocol hierarchy and “h” bytes of data are added at each layer.

• So the total number of header bytes is  ; therefore, the space wasted on the headers of the layers is  .

• Each message generated by the application is M-bytes long; so add “M” with total number of header bytes.

o Thus, the total message size is  .

• Divide the total number of header bytes by total message size to calculate the fraction of bandwidth wasted on headers.



Therefore, the fraction of the network bandwidth filled with header is 

Answer 2

Answer:

The fraction of each packet used by the protocol is nh/(M+nh).

Explanation:

We have n layers of protocol, with h bytes added at each tier, for a total of nh header bytes.

Because the payload is M bytes, the total packet size is M + nh bytes.

As a result, protocol headers account for nh/(M+nh) of each packet.

This is a severe simplification, because each layer will have its own protocol headers, each of which will be distinct in size. Furthermore, routers may alter the size of protocol headers along the way.

Conclusion:

nh/(M+nh) is the fraction used by protocol for each packet.