ICMP

Creator
Creator
Seonglae ChoSeonglae Cho
Created
Created
2021 Mar 20 4:37
Editor
Edited
Edited
2023 Nov 22 3:26
Refs
Refs

Internet Control Message Protocol

ICMP report TCP/IP issues during processing IP packet for detecting anomaly cases like
  • Host is off
  • Link is disconnected
출발지호스트에 이러한 사실을 알려야하지만, IP does not specify this issue reporting method.
traceroute
use ICMP too
 

How ICMP works

ping
is used for ICMP. There is no transport layer required.
 

ICMP message

type, code plus first 8 bytes of IP datagram causing error
notion image
 
 
 
 
 
 

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