ICMP Protocol

author: Nathan Acks
date: 2022-03-30

ICMP headers are 8 bytes; the first 4 bytes have a fixed meaning, while the meaning of the last 4 bytes varies depending on the type of request specified in the first 4 bytes.

ICMP traffic “types” correspond to the kind of packet being sent (though different ICMP services can have multiple types):

Ping packets typically just include either random data or all zeros.