Twinning problem

[liquidshokk]

Does anyone else have loads of problems with mobile twinning on V8/V9?

Customer has an IP500 V2 with both SIP and ISDN lines, which were installed on v8 but then upgraded to v9.0.5 (to resolve other issues) and I have just upgraded them to latest 9.0.8. They have two sites, the main site where the ISDN and SIP are located and a remote site which just has 16xx phones connecting back via VPN

We have a long running issue with one customer wanting to twin their desk phones with their mobiles, where either the wrong voicemail service answers (have played with mobile answer guard, changing the mobile voicemail timer etc), the wrong CLI is presented for various types of twinned calls (transferred via other users, callers from mobiles, calls to DDI's etc) and various other bizarre behaviours.

The current issue is that they want to have a huntgroup with two users in, who are sometimes logged in to their phone in the office and other times working from home on their mobile so they are both twinned and are members of the collective huntgroup. Without having to know if the users are in the office, the receptionist wants to call the huntgroup and whichever user is available should be able to take the call wherever they happen to be. The customer was reporting that sometimes the mobile voicemail would kick in on one of the phones, meaning the call couldn't be answered by either desk phone or the other mobile. Should this setup be ok if mobile answer guard is enabled? The affected user is located at the remote site, connecting over VPN but I believe the same happens for users at the main site. Twinned calls to users own DDI did previously work fine..

However...to make matters worse, since the upgrade from 9.0.5 to 9.0.8 when calls are presented to the mobile and you answer, the desk phone carries on ringing and you don't hear anything on the mobile... Nothing has been changed other than the upgrade being carried out. With 9.0.8 being the latest 9.0 version I'm not sure what else to do....

 

[liquidshokk]

I've just changed the user settings to go out via the ISDN rather than SIP and twinning is fine, so it is a SIP issue (always)....

 

[liquidshokk]

I've spent a day onsite testing the twinning issues that the customer has and I've found out the below;

Twinning works fine when using ISDN lines for the outbound leg of the call twinning. This includes huntgroup twinning with multiple users in the group.
Users were logging off their desk phones meaning that when the twinned mobile is turned off the call is hitting the mobile voicemail as there's nowhere else to go, regardless of what the mobile answer guard is set to and having twin when logged off enabled (never answered by deskphone voicemail). This was mainly an issue when included in a group, as the call wasn't getting to the other members of the group whose mobiles were on. Presumably this is by design. Have advised customer to leave deskphones logged in and use mobile answer guard to ensure that the desk phones of all group members ring.

The main issue I'm having is twinning over SIP. I've found that if a users DDI is called and it twins with and is answered on their mobile the outside caller continues to hear ringing and the person answering the call hears silence. If you call into reception and the call is transferred to a twinned user and answered on the mobile the speech path is fine. Surely this means the firewall configuration is ok and it is the IP Office not passing the right messages on direct DDI calls that are twinned?

 

[Pepp77]

For the SIP are you using STUN?
Do you have keepalives setup on the VOIP tab of the LAN you are using for SIP?
What firewall?

I recently setup a customer with twinning on SIP. I found that if I didn't use STUN I got no speech on the twinned call, if I used STUN and thus the keepalive options were valid I got speech no issues. The symptoms were exactly the same as you describe.

| ACSS SME |

 

[liquidshokk]

Yes using STUN, the result is Full Cone NAT and the outside caller always hearing ringing even when answered on the mobile. I have keepalives enabled on the LAN the calls are going out of (tried RTP and RTP-RTC) and tried timeout as 60, 15, 10, and 8 but get the same result. The only way I can get dead air both ways is to manually choose a firewall type other than Full Cone NAT. I am using LAN1 as the transport option on the SIP line, with this set to None I also get no speech.

 

[amriddle01]

This certainly sounds like an interfering router to me

 

[liquidshokk]

And it happens to be a draytek amriddle01

 

[Westi]

I have the same problem on R9.1 since I upgraded from 8.1
No audio on twinned calls when using SIP trunks and a friend has the same issue so he downgraded again to 8.1

I am not sure what it is in R9.1 that breaks it but also didn't have the time or motivation to start troubleshooting my own crap because I rarely use it.

Joe W.

FHandw, ACSS (SME)


"This is the end of the world, make sure to buy your T-shirt before it is too late"
Original expression of my daughter

 

[liquidshokk]

I convinced the IT company to let me have access to the draytek router and found they had only opened 5060 and not 4000-60000 as I'd requested a long time ago. As soon as I did this and changed the firewall type to open internet in network topology twinned calls were fine regardless of how the call ended up at the mobile.

 

[Westi]

I have the RTP range forwarded because my remote phones work no problem when I use them. But I will double check because you never know maybe I was mentally off one day and logged in and "secured" my firewall because I didn't use them for a while.

Joe W.

FHandw, ACSS (SME)


"This is the end of the world, make sure to buy your T-shirt before it is too late"
Original expression of my daughter

 

[sagbab]

There seem to be a lot of mobile twinning issues from 9.0 onwards. For me after upgrading to 9.1.2 the system didn´t treat the calls as busy even though there is an ongoing twinned call. Found this in the releasenotes (Tech Bulletin 183) for 9.1.4 that I hope resolve these issues, but haven´t had time to test it yet.

IPOFFICE-97069 Mobile twinning and FNE features failing following upgrade from 9.0.1 to 9.1.2