What is Symmetric NAT?

[Paul Westwell]

Hi,

What is the difference between NAT and Symmetric NAT and how might this
effect MSN messenger?

Regards,

Paul

 

[Jonathan Kay [MVP]]

Greetings Paul,

There are several types of NATs, based upon how exactly the "NAT" operations are being
performed. A symmetric NAT is one in which all requests from the same internal IP and port
to a specific destination are mapped to the esame external IP address and port.

In MSN Messenger 6.1 and above (not sure if 7 changes any of this yet), for features that
require a direct connection (to either work or work well) Symmetric NATs are not supported
unless they support UPnP.
____________________________________________
Jonathan Kay
Microsoft MVP - Windows Messenger/MSN Messenger
Associate Expert
http://www.microsoft.com/windowsxp/expertzone/
Messenger Resources - http://messenger.jonathankay.com
All posts unless otherwise specified are (c) 2004 Jonathan Kay.
You *must* contact me for redistribution rights.