MSN Messenger Service

[amamitzsch]

One of our clients is using a PIX 525 whith SW 5.32. Now they have requested to enable the MSN Messenger service for their end users. Basically, it was not a problem, we have opened the port 1863 and could establish a connection to an outside user. The only feature which does not work is the direct file transfer between two clients. Is there any further configuration needed in order to enable this feature ? The inside clients use either NAT or PAT. We also have a couple of users for which we defined static translations. None of these configurations allow direct file transfers.

Any ideas ?

Thank you in advance,

Andre

[bwalchez]

Take a look at your PIX debugging logs to determine which ports it’s trying to use. I’m guessing it’s a high random UDP port. You’ll probably have to open that range and it most likely won’t work with your PAT clients. You might try some newer PIX code. They’re always adding new fixups for such application compatibility.

[gbbromley]

MSN IM uses a whole raft of ports and protocols. The real problem is the lack of documentation that supports it.

From debugging 'memory' the following are required inbound I think (I think its all TCP, but not sure):

6891-6900 - MSN IM File transfer

Other parts of MSN IM use other ports and protocols, which PIX can handle e.g. H.323.

Given the ranges involved, we dropped the idea of using MSN IM for file transfer, and instead forced users to use document management systems like Livelink which is Web friendly ;)

[joyler]

Microsoft has a few Knowlegebase articles on this topics that could give you the insight you are looking for. You can start with "MSN Messenger Service Cannot Perform File Transfers or Make Voice Connections Through NAT (Q278887)" but I believe you will need to do some more searching as well.

[awalnet]

Hi

For file transfer, Both incoming and outgoing TCP connections use this range of ports: 6891 to 6900. This allows up to 10 simultaneous file transfers per sender. If you open only Port 6891, users will be able to do only one file transfer at a time.

I hope it would help you.

Best Regards

Zeshan Mansoor Jalali

Network & Systems Engineer-AwalNet-Al-faisaliah Group

CCNA,CCNP,CCDA,CCIE(R&S)written, Cisco Security Specialist,MSCE+I