8. ICMPv4 and ICMPv6: Internet Control Message Protocol
8.1. Introduction
The IP protocol alone provides no direct way for an end system to learn the fate of IP packets that fail to make it to their destinations. In addition, IP provides no direct way of obtaining diagnostic information (e.g., which routers are used along a path or a method to estimate the round-trip time). To address these deficiencies, a special protocol called the Internet Control Message Protocol (ICMP) [RFC0792][RFC4443] is used in conjunction with IP to provide diagnostics and control information related to the configuration of the IP protocol layer and the disposition of IP packets. ICMP is often considered part of the IP layer itself, and it is required to be present ...
Get TCP/IP Illustrated, Volume 1: The Protocols, 2nd Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
