Parameter: Filter by proxy address

The Filter by proxy address parameter is used to control if the source IP of incoming SIP invites are compared with the Proxy address field of the NAP in order to determine if the call is coming from this NAP.

(This function has no effect on outgoing SIP calls on this NAP)

When this parameter is enabled

When this parameter is enabled (which we highly recommend), only incoming calls from a source IP address that matches the Proxy address of this NAP will be considered as coming from this NAP.

When this parameter is disabled

When this parameter is disabled (not recommended), any incoming call received on the local SIP Transport Server of this NAP will be considered as coming from this NAP.

This may cause multiple NAP to "match" the incoming call, in which case one of the matching NAP will be associated with the call (it's undefined which will be chosen).

Note that this can be used to create a "default" NAP that accepts any incoming call.