What is ICMP?

codedv · 01-04-2004, 05:10 AM

I've heard it mentioned many times but don't really know what ICMP is and what its purpose is.

Where does it fit into the OSI model?
What applications does it have?
How do you know if someone is communicating with you using ICMP?
and are there any security implications of using it?

Thanks in advance.

XavierP · 01-04-2004, 05:28 AM

One quick Google search later.....

http://www.webopedia.com/TERM/I/ICMP.html

ugge · 01-04-2004, 10:12 AM

ICMP stands for Internet Control Message Protocol.
One of the most common uses are the ping command that send an ICMP Echo packet.
The reply to that would be a ICMP Echo Reply.
ICMP belong in the Network layer of OSI.