Re: ICMP Well-Known Port

[lk-m-wizards () bigears solsoft com (Lorens Kockum)]

On firewall-wizards wpl1 () jps net wrote:
> This is a multi-part message in MIME format.
[...]
> Evidently I'm really missing the boat.

Quite; posting multi-part MIME with text and HTML on a mailing
list, thus doubling or conceivably tripling list volume,
certainly qualifies as missing the boat.  Some programs actually
try to make the choice for you, and getting them to change their
mind can be a real pain.

> I've been trying to find the
> well-known port for ICMP.  Is there no such thing?

No, there is no such thing.  A "port" is generally taken as
referring to a TCP or UDP port.  ICMP is not part of TCP or UDP,
it is a subset of IP in its own right.

Let me clarify that.  IP is divided into IP protocols. Number 1
is ICMP, number 6 is TCP, number 17 is UDP.  There are others,
like, ummm, IGMP. TCP and UDP have source and destination ports,
some of which are more or less "well-known", while ICMP has
a type and a code (the code qualifies the type), which are
standardized.

When someone says "TCP/IP", in my experience they always
refer to at least "(TCP and UDP and ICMP)/IP", it may even be
officialized somewhere.

Hope This Helps,