Functionality of Early Media

Discussion in 'Ideas' started by Stefan Irniger, Jan 3, 2018.

  1. Stefan Irniger

    Nov 27, 2017
    Likes Received:
    I tested a 3CX Phone System with a SIP provider, which uses SIP-to-SIP Gateways (in this case a Patton SN5300).
    We found an issue with the usage of early media:
    - We started a call to a number which is chargeable
    - The early media text comes to the 3CX Phone System
    - The 3CX Phone System don't provide the incoming text to the phones.

    Our tests showed:
    - When the first "183 Session Progress" comes without SDP and the second with SDP, then it is ignored.
    - A correct behavior would be, that the content always can be updated. (view of the provider).
    - If the SBC (Patton) enforces, that "183 Session Progress" always has an SDP at the beginning, Early Media works. But this is a workaround and not a solution.

    Further informations:
    - The option ENABLEEARLYMEDIA don't work for this
    - PBX Deliver Audio makes no difference
    - Request from discussion in Support Ticket #170855