Hi Guys,
Does anyone understand exactly how RTP ports are chosen by the IP Office? We have a customer on Gamma SIP, no SBC, who has been working fine for a number of years, but as of yesterday is getting one way speech. They on R11.0. We logged this with Gamma, and after investigating for most of they day they came back to say:
After analysing the examples provided during the media trace time span, many thanks for performing those test calls.
I have determined that the reason One-Way Audio is apparant for your customer is due to a Port Negotiation with the RTP Streams themselves, which is no longer accepted behaviour on the new SWe SBCs your customer has been upgraded to.
Please find the attach screen capture of one of the test call examples, of the RTP Flow. You will see, the Incoming RTP media stream is delivered to a Port of 49154 as requested in the 200 OK response to the initial INVITE. However, Media that is being sent from site is coming from Port 59401.
As advised, this type of behaviour was accepted on the MSX SBCs, but now your customer has been upgraded to our new SWe SBCs this behaviour is considered invalid.
To amend, could you please ensure, that the Media Port that RTP is sent from, is the also the same port used to receive incoming RTP.
I have attached their image also.
My first though was that this would be an affect of the Firewall/NAT type selected, it is currently set to Static Port Block which is what we tend to use with IPO on Gamma; however I have been through each NAT type in turn, and none have worked. Also, 59401 is not part of the RTP port range.
Any ideas what could be causing this, and how to stop it?
Thanks
Joe
Joe Newton
Does anyone understand exactly how RTP ports are chosen by the IP Office? We have a customer on Gamma SIP, no SBC, who has been working fine for a number of years, but as of yesterday is getting one way speech. They on R11.0. We logged this with Gamma, and after investigating for most of they day they came back to say:
After analysing the examples provided during the media trace time span, many thanks for performing those test calls.
I have determined that the reason One-Way Audio is apparant for your customer is due to a Port Negotiation with the RTP Streams themselves, which is no longer accepted behaviour on the new SWe SBCs your customer has been upgraded to.
Please find the attach screen capture of one of the test call examples, of the RTP Flow. You will see, the Incoming RTP media stream is delivered to a Port of 49154 as requested in the 200 OK response to the initial INVITE. However, Media that is being sent from site is coming from Port 59401.
As advised, this type of behaviour was accepted on the MSX SBCs, but now your customer has been upgraded to our new SWe SBCs this behaviour is considered invalid.
To amend, could you please ensure, that the Media Port that RTP is sent from, is the also the same port used to receive incoming RTP.
I have attached their image also.
My first though was that this would be an affect of the Firewall/NAT type selected, it is currently set to Static Port Block which is what we tend to use with IPO on Gamma; however I have been through each NAT type in turn, and none have worked. Also, 59401 is not part of the RTP port range.
Any ideas what could be causing this, and how to stop it?
Thanks
Joe
Joe Newton