NEC sl2100 RTP sending to wrong IP

[MartijnE]

Hi all,

I have a NEC sl2100 with the latest firmware.
I am trying to connect the pbx with a Call2teams. A solution that integrate the onprem pbx with MS Teams.

The registration of the SIP client(MS Teams) is done without any issue, the signaling is working fine. But there is No audio.
I did some wireshark traces and there is something weird going on.
Teams is sending the RTP packet from the ip xxxx and the pbx is replying to yyyy.
Where yyyy is the IP address of the sip registration and not the ip xxxx where the rtp packet originally comming from.
I am using NAT and SIP ALG is disabled. Other sip phones are working Fine.

Does someone know the solution for this issue?

Thanks.

 

[John Robertson]

Have you added your NAT router in 10-12? Do you have 10020 thru 10563 forwarded on the firewall to the address in 84-26?

 

[MartijnE]

Yes I did that and other third party sip phones are working fine.

 

[John Robertson]

Can you attach the wire shark, and where the RTP packets are coming from? and where they should be coming from?

 

[MartijnE]

Hi John,

Please find the Wire shark included.

The start op the voipcall is on line 232.
On line 595 there is a rtp packet comming from teams to my VOIPdaughtercard (172.16.5.3).
The voip card is replying to 3.11.215.246 instead of 52.149.75.31(where the RTP pakcet is comming from)

 

[John Robertson]

Can you also send a copy of your SL2100 database? Change your transport protocol to UDP instead of TCP. All NEC phones I have ever done have been UDP. Lets look at your database and I will let you know what I find there.

 

[MartijnE]

Hi John,

I tested both UPD and TCP,no result.
Please find a copy of the database.

 

[John Robertson]

I cannot open the database. What version of PCPro are you using?

 

[MartijnE]

The latest 3.0 EMEA version

 

[MartijnE]

Hi ,

After some troubleshooting, I see following error in the DIM trace:

VPR PROC INITIAL ERROR:: HDSP_ERR_RTP_RETRY_TIMES (00-0000:MSG_FROM_VDCT)

Does someone know what this means?