NAT

[Aljaz Tomaz RDSI]

Hi all!
I know that this topic is not directly associated with IPv6 but I would like
to find some information about NAT implementation. NAT has to chage every
source/destination IP address and source port every packet outside NAT
domain (whole inside network is maped to one legal IP address). For all
TCP/UDP communication I found no problem doing that. What about PING (echo
request/reply) - ICMP packets. There is no UDP/TCP port. How NAT works in
that situation and distinguish packets?

Regards,
Tomaz