NAT Polycom Endpoint

[Video_Man]

Hi everybody!!!Long time i have not posted my views neither have i posted a problem.

This time i am trying to NAT an Endpoint which is in Germany which has got a Public IP and we have extended a private network to them to which we want to NAT it.On connecting to the end-point on the Private IP the connection is established but there is no audio and video getting through when the conference is scheduled through the MGC -100v 6.0;wheras if i dial directly to that end point from any other end point in my office ,i can get their video and audio clearly wheras they do not get anything from our side.
I am from a company in India which has taken over this company in Germany and wish to establish the IP connectiivty between them.Also they have a firewall at their end which is outsourced to the HP guys there and according to them they have set the policy to not drop any packets coming from our Private IP.
Also they have proerply configured the NAT addresses in the end point.So i really do not understand where does the problem lie.
Can anyone help me out with this????

[Glen Sykes]

Hi Video Man!

Firstly, the NAT address in the polycom is not the only peice of the puzzle here, there must also exist in the NAT itself a NAT mapping between the inside address that the polycom resides on, and the outside address that you wish the polycom to use. It is also important that no other device shares this outside address with the polycom (in other words a 1 to 1 address mapping). If you are using a Cisco NAT, the way I would recommend would be to use a static NAT mapping, although dynamic does work if you know what you are doing. What doesn't work is Port Address Translation, sometimes referred to as overloading, where a single public IP address is shared between multiple devices. H.323 does not like this.

You will not be able to achieve this type of NAT resolution using your MGC, simply because you cannot configure it to 'know' it is behind a NAT, instead you will need what is becoming increasingly known as an Application Layer Gateway for H.323. This device works in conjunction with a Gatekeeper and will take your H.323 traffic across your NAT seamlessly.

For the firewall, again depending on which firewall it is determines the best solution. The easiest way for a quick fix is to open all ports between the source and destination addresses only.

For a better answer I will need more info on your NAT and Firewall hardware.

Cheers,

Glen

[Hariharan.I.D]

I recently faced similar issue with a Dlink DSL Router configured as NAT connecting a VSX7000 to the internet.
The engineers of the BroadBand Service Provider were rude
and did not co-operate with me.
Ultimately I asked the customer to threathen the ISP
to discontinue their services and go with a competitor ISP.
Any way that was logistics issue.
Now coming to the techical issue,
atlast the H.323 calls through internet worked after making
the Dlink DSL Router to act as Transparent bridge and
by configuring Public Static IP directly on the VSX.
May be its a bug with the current version of the router?

[Glen Sykes]

most routers will not transparently NAT h.323 traffic. There is a thread here H.323 Aware NAT routers (http://www.vtctalk.com/showthread.php?t=12888) where users are asked to post the make / model of router that they have encountered that do support H.323 NATing.