Abstract


  • Can be used to gauge the latency between devices.
  • If a packet is too large, the router will drop it and send an ICMP message back to the original source.

Attacks

  • ICMP flood attack: each ICMP echo request requires an ICMP echo reply from the server, which consumes computational resources.
  • Ping of death

ICMP Packet

  • An ICMP header follows a normal IP header.
  • When a router or server needs to send an error message, the ICMP packet’s data section always contains a copy of the IP header of the packet that caused the error.

ICMP Mechanism


  • Not associated with transport layer protocols such as TCP or UDP. Therefore, ICMP is connectionless; one device does not need to open a connection with another device before sending an ICMP message.

Important

The ICMP protocol also does not allow for targeting a specific port on a device.

References