Protocol for Icmp IP

ICMP stands for the Internet Control Message Protocol. It is a separate protocol from the Internet Protocol (IP), but complements IP and only exists to compensate for the shortcomings of IP. It creates a method to pass control messages during an IP transmission.

Function

• The Internet Protocol has no mechanism to check whether data packets sent out by a computer actually arrive undamaged at their destination. This absence of function was intended by the designers. IP is meant to work in cooperation with the Transmission Control Protocol, which manages connections and checks data integrity. However, when IP started to be used without TCP, it was noted that some form of error checking was needed for IP. This is why ICMP was defined.

Features

• The definition of ICMP includes 42 standard messages. ICMP reports back to the sender if the destination is not available, if the transmission timed out before arrival, if the destination refused to accept the data packet for some reason or if an alternative route is suggested. ICMP also looks for endpoints through a query mechanism and checks on the destination computer's operating status.

Failure

• ICMP does not monitor the success or failure of its own message packets. This is to avoid a recursive loop of error packets about error packets in error.