Comments on: Office Communications Server 2007 R2 Audio/Media Negotiation

By: eshudnow

eshudnow — Fri, 30 Jul 2010 00:37:09 +0000

Just don't open UDP. The ICE connection testing process tests both TCP and UDP at the same time, and if both works, UDP is provided to the client. If UDP fails but TCP works, TCP is provided to the client.

By: Ravi Biradar

Ravi Biradar — Thu, 22 Jul 2010 18:41:14 +0000

Hi Elan .
I am using External user
I want block UDP ports or make udp ports unreachable so that ICE negotiation happens only in TCP, how to go about it any docs?

Thanks in Advance,
Ravi

By: moto822

moto822 — Wed, 14 Jul 2010 15:42:28 +0000

Hi All,

So if I am understanding correctly, I need to open up 3478 or 443 from my client network to my DMZ to get peer to peer to work?

By: Elan Shudnow

Elan Shudnow — Fri, 02 Jul 2010 13:32:01 +0000

Thanks, will update.

By: DrRez

DrRez — Fri, 02 Jul 2010 05:13:13 +0000

Good article Elan. I confirmed with the principal program manager for media in Microsoft's Communications Server team. There's a slight incorrection. UDP 3478 and TCP 443 are tried in parallel, not in sequential order.

By: eshudnow

eshudnow — Tue, 29 Jun 2010 16:44:30 +0000

I believe so. This is the 1 scenario I'm not 100% certain on.

By: eshudnow

eshudnow — Tue, 29 Jun 2010 16:31:04 +0000

I learned this through Escalation Engineer where he told me this and we verified it via the log files that Communicator generates. It's also discussed on a webcast that Byron Spurlock presents in.

By: Pawel

Pawel — Sat, 19 Jun 2010 19:34:21 +0000

Hi Elan!

Many thanks for great article.
I was thrilled to find out that scenario described in "Two Users Internal to the Network (media ports closed)" section is true indeed.
Is this documented somewhere on MS technet?
I thought that in case of p2p failuer two internal users would connect via Front-End server, like in case of every conference.
Why are they routed via Edge?

My question:
If I force clients from two separate sites (subnets) to use required minimum 40 media ports, does this mean that amount of concurrent calls between these sites is limited?
Each Communicator p2p call uses min. a few media ports, so max. number of conurrent calls is like ~10 in this case?

By: Philip

Philip — Thu, 17 Jun 2010 22:13:28 +0000

Is it possible to require 128 bit encryption on port 443 for the Edge server since it is Internet facing even though MOC clients use 128 bit already?

By: Ahmed Khalil

Ahmed Khalil — Thu, 17 Jun 2010 06:22:08 +0000

Hi Shudnow,
Please confirm the following:
If two users on the Internet can't start Peer to Peer connections, they will bridge the communications betwen them by using A/V Edge.
Is that means also they will have A/V Edge in the middel all the time for the Peer to Peer connection.

Regards