How to allow for Video & Audio

Contrary to what have been said and written many times before, it is possible to allow for Video & Audio without the use of Q.931 and gatekeeper.

One of the things that are said most often are, that MSN Messenger Video works only if the firewall is Universal Plug & Play capable. As the ISA Server is not a UPnP firewall, it shouldn't work.

But it does. All you need is the ISA Firewall Client installed, create a protocol definition to be used for this sake, and a protocol rule which includes the newly created protocol definition and some more, change the firewall client configuration file.

Step by step
[ol 1]
[li]Create a new protocol definition, and name it "MSN Messenger Video & Audio" for example:[/li]
[ul square]
[li]Primary Connection: Port 1863, TCP, Outbound[/li]
[li]Secondary Connections[/li]
[ul circle]
[li]Port Range From 5004 to 65535, UDP, Send Receive[/li]
[li]Port Range From 6891 to 6900, TCP, Inbound[/li]
[li]Port Range From 6891 to 6900, TCP, Outbound[/li]
[li]Port Range From 6901 to 6901, TCP, Outbound[/li]
[/ul][/ul]
[li]Create a protocol rule to allow for this newly created protocol AND Net2Phone[/li]
[li]Edit the Firewall Client Properties (from within ISA Management or directly into the mspclnt.ini file). Older Messenger versions are called msmsgs, current version 6.2 is called msnmsgr. Add NameResolutionForLocalHost=E and RemoteBindUDPPorts=0,6901[/li]
[/ol]

The "NameResolutionForLocalHost=E" is used to tell what IP address to resolve. E=External IP Address of ISA Server, and "RemoteBindUDPPorts" specifies port(s) to bind remotely.

A collection of links that have helped me - and hopefully will help you out there too:
[link http://support.microsoft.com/?id=284554]How To Add Support for MSN Messenger Net2Phone in ISA Server 2000[/link]
[link http://support.microsoft.com/default.aspx?kbid=323457&product=isas]Firewall Client Program Settings for Configuration Files Like Wspcfg.ini[/link]