Conversion SIP Trunk -> PRA for old Alcatel PBX

[Tomasz Hinz]

Hello.

I have a problem. I change the link PRA from Orange, because it was expensive. I decided I will use SIP-Trunk from one of polish service providers, because we have an older Alcatel PBX  I used a Cisco router that converts my SIP trunk to PRA. At the desks of employees we have digital Alcatel phones and normal analog other brands. Here comes the problem. If I calls to a phone number on digital Alcatel desk phone - waiting tone is normal, but when I call the phone number on the analog desk phone I hear silence, the silence but the analog phone ringing normally. When a worker lifts the phone conversation takes place without obstacles. This event is also reflected in the logs ....

Here is debug q931 output for proper  connection for digital Alcatel phone

Oct  7 21:37:33.544: ISDN Se0/0/0:15 Q931: Applying typeplan for sw-type 0x12 is 0x2 0x8, Calling num 48607338338
Oct  7 21:37:33.548: ISDN Se0/0/0:15 Q931: Sending SETUP  callref = 0x0215 callID = 0x8196 switch = primary-net5 interface = Network
Oct  7 21:37:33.548: ISDN Se0/0/0:15 Q931: TX -> SETUP pd = 8  callref = 0x0215
        Sending Complete
        Bearer Capability i = 0x8090A3
                Standard = CCITT
                Transfer Capability = Speech
                Transfer Mode = Circuit
                Transfer Rate = 64 kbit/s
        Channel ID i = 0xA18381
                Preferred, Channel 1
        Calling Party Number i = 0x2880, '48607338338'
                Plan:National, Type:National
        Called Party Number i = 0xA8, '818280111'
                Plan:National, Type:National
Oct  7 21:37:33.568: ISDN Se0/0/0:15 Q931: RX <- CALL_PROC pd = 8  callref = 0x8215
        Channel ID i = 0xA98381
                Exclusive, Channel 1
Oct  7 21:37:33.592: ISDN Se0/0/0:15 Q931: RX <- ALERTING pd = 8  callref = 0x8215

And here you can see the same debug for analog phone, where I have no any tone during the wait for connection.

Oct  7 21:36:38.943: ISDN Se0/0/0:15 Q931: Applying typeplan for sw-type 0x12 is 0x2 0x8, Calling num 48607338338
Oct  7 21:36:38.947: ISDN Se0/0/0:15 Q931: Sending SETUP  callref = 0x0213 callID = 0x8194 switch = primary-net5 interface = Network
Oct  7 21:36:38.947: ISDN Se0/0/0:15 Q931: TX -> SETUP pd = 8  callref = 0x0213
        Sending Complete
        Bearer Capability i = 0x8090A3
                Standard = CCITT
                Transfer Capability = Speech
                Transfer Mode = Circuit
                Transfer Rate = 64 kbit/s
        Channel ID i = 0xA18381
                Preferred, Channel 1
        Calling Party Number i = 0x2880, '48607338338'
                Plan:National, Type:National
        Called Party Number i = 0xA8, '818281555'
                Plan:National, Type:National
Oct  7 21:36:38.967: ISDN Se0/0/0:15 Q931: RX <- CALL_PROC pd = 8  callref = 0x8213
        Channel ID i = 0xA98381
                Exclusive, Channel 1
Oct  7 21:36:38.991: ISDN Se0/0/0:15 Q931: RX <- ALERTING pd = 8  callref = 0x8213
        Progress Ind i = 0x8582 - Destination address is non-ISDN

Of course I put effort to fix this problem using archival information from forum and other publications but I can’t find proper solution. I tried also article http://www.cisco.com/c/en/us/support/docs/voice/h323/22983-ringback.html but with no success.

Please help, how to set a valid wait tone for analog connection in this case ?

[Ayodeji Okanlawon]

This is most likely because the analogue phones are sending inband message in the progress indicator. We can see this from the ISDN logs, which is not present in the digital phones.

Oct  7 21:36:38.991: ISDN Se0/0/0:15 Q931: RX <- ALERTING pd = 8  callref = 0x8213
        Progress Ind i = 0x8582 - Destination address is non-ISDN

This is because usually analogue ports/devices always send 183 Session Progress.

Where are these analogue phones connected? On a cisco router? if they are then you can use the command below to get them to send alerting (180 ringing) to the sip provider.

voice call send-alert

[Tomasz Hinz]

Thank you for your response

Cisco works only as "Media converter" , all phones are connected to Altel PBX. I tried this command (voice call send-alert) and I unfortunatelly still have no wait signal ...

[Ayodeji Okanlawon]

In that case this is not a Cisco problem. You need to get your altel PBX to send alerting to the Cisco gateway. This is equivalent to sending 180 ringing instead of the 183 session progress been sent now

[Alexey Platov]

First of all AFAIK Alcatel always provides ring-back tone over PRA. So it shouldn't be a problem between Cisco and Alcatel.

So you'd better check SIP trace between Cisco and your provider or connect any phone to Cisco router and check whether it gets ringback tone when calling analog set. If it gets - then it's your SIP provider's problem.