ICMP Parameter Problem messages

ICMP Parameter Problem messages are used to indicate that a host or router could not interpret an invalid parameter in an IPv4 datagram header. When a host or router on the network find a bad parameter in an IPv4 datagram header, it will drop the packet and send an ICMP Parameter Problem message to the original sender. ICMP Parameter Problem message also has an option for a special pointer to inform the sender where in the original IPv4 header the error had occurred.

ICMP Parameter Problem message Type number is 12. Code field values of ICMP Parameter Problem message are explained in below table. Please click next link to know more about Type and Code fields in ICMP header