Ringback problem with Ericsson MD110

[ifallani]

Hi everybody,

anyone out there knows how to override the Alert Progress Indicator that comes from an ISDN E1?

The problem is: we have a voice gateway connected via an E1 interface to an Ericsson MD110 PBX (NOT Qsig). An outbound call from the Voip infrastructure (CUCM 6.1 + IPPhone + VoiceGW) works fine but no ringback is heard by the user. The Q931 trace of the E1 beetween the vgw and the PBX is showing that the PBX is sending an Alert PI = 2 (destination is not ad ISDN) and if I'm understanding correctly, ringback tone is expected from the PBX, which is not.

PBX people tells me that the MD110 is not able to play ringback tone and every progress_ind commands on the gateway seems to not work. If I could ignore the PI value that comes from the ISDN, maybe I can fix the problem with "tone ringback alert-no-PI" command but I'm not that sure that a solution exists, beside the MD110 to start to play tones magically...

Thank you for your help.

[irisrios]

The PBX has set the Progress indicator to indicate that the tone is 'INBAND' - SO the PBX should be providing the ringback tone inband - possibly they are not doing that. In order to confirm whether the PBX is sending / not sending the ringback inband, do a 'PCM' trace on the gateway.