The entry fields "Asserted Identity" within Gateway Groups enables an outgoing Call Forward of an originally PSTN call

via a SIP Trunk.

Normally SIP provider check the calling number of an outgoing call because they are committed to ensure the correctness

of the used CLI.This is done by the network provided value "Asserted Identity".


If Call Forward is configured and an incoming call from PSTN is redirected towards the PSTN via a SIP Trunk the following

aspects must be respected.

  • Without the use of the "Asserted Identity" function the PBX keeps the origin calling number
    within the outgoing SIP message. If this calling number is unknown for SIP provider the call is rejected.
  • With the use of the "Asserted Identity" function the PBX replaces the origing calling number  with the calling number
    of an own extension. The provider recognizes the calling number as own  number and accepts the call.


Administration Settings

The administrator must configure "Asserted Identity" in the following way. The first row contains the seach pattern for all

^(.*) and the second row the replaced line number (in this example +492871...)  along with extension number ($1).

The PBX uses automatically as extension the number of the forwarded account.



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