RE: Removing ping/icmp from a network

["Joachim Thuau" <jthuau () heavy-iron com>]

> From: Jason Thompson
> Subject: Re: Removing ping/icmp from a network

[snip]

> I don't see any ICMP messages that are a MUST for network operation.

The one system that I know makes use of ICMP messages is Active
Directory. 
It uses ICMP to establish a number of parameters regarding speed of the
links 
between Clients and Domain controllers. See the note at the following KB

article for some details:
http://support.microsoft.com/kb/227260/

With this in mind, you could setup rules for ICMP traffic to only be
allowed 
to Domain Controllers, which would be sufficient for normal operation of
AD.

Jok