Changing port for C20

[hashimoto.kotaro]

Hi everyone,

Our customer tries to establish a call from C20 to Sony endpoints as shown in attached file.

As far as I know, C20 can not change the port number used for dialing.(designating port 1721 instead of 1720)

Does anybody know if it is possible?

FYI)

Sony endpoints can change their ports generally used for Q.931.

Kotaro

[Teck Chye Tang]

Hi,

You cannot change the signalling port, you can only change the RTP ports.

xConfiguration H323 Profile 1 PortAllocation: Dynamic

*c xConfiguration RTP Ports Range Start: 2326

*c xConfiguration RTP Ports Range Stop: 2486

Regards,

[Tomonori Taniguchi]

If I’m not mistake, Sony PCS Endpoint supports 1721 signaling port to improve interop between GnuGK (GnuGK default port is 1721 but also support 1720), but not to be flexible for standard H.323 call signal (H.225 standard signal is 1720).

[Tomonori Taniguchi · Accepted solution]

So just to clarify, if Sony Endpoint configured to listing incoming H225 signal from port 1721, C20 won’t able to negotiate the call (while both Endpoint are not registered on Gatekeeper).

[hashimoto.kotaro]

Hi Teck , Taniguchi-san,

Thank you for your information.

I understand C20 can't change the signaling port manually.

By the way, by deploying gatekeepers on both side,  is it possible to negotiate the call between them, even if one endpoint uses 1721 as signaling port?

Kotaro

[Tomonori Taniguchi]

I’m not aware any other gatekeeper other than GnuGK which support 1721 for H.225/RAS communication.

GnuGK does support 1720/1721 in parallel (unless I miss understand their implementation), however this is not standard port for H.323 call signaling.

Therefore I strongly recommend staying with 1720 for H.225 signaling port to ensure there is no unexpected behavior in later phase (typically this type of deployment cause problem in future extension).

[hashimoto.kotaro]

Hi Taniguchi-san,

I see your point.

We recommend our customer not use 1721 for H.225 signaling instead of 1720.

Thank you for your advise.

Kotaro