What basic functions does the IPv4 header checksum field perform?

H1————R1————R2————H2

Suppose you want to send a packet from host H1 to host H2. The packet may get corrupted due to various reasons like interference, fading etc. In that case, IPv4 header checksum helps us to find out whether the packet has been received correctly received or not. Note that the checking is done only at the header part, not on the data part. The reason is that data checking is already done at the transport layer. Another point is that we are not correcting it we are just identifying it. To find the checksum we use 1’s complement method.

Please visit my blog for knowing more information on network