When the PSTN provider redirect their DDI numbers in case of emergency to another bearer they simply send all redirected DDI numbers to the main number associated with this new bearer. So at the end we have a picture as in the bit of the Q931 trace below
Component = Invoke component
Invoke Id = 16384
Operation = Diversion Leg2
Calling Party Number i = 0x2183, '7973715225'
Called Party Number i = 0x81, '179741'
*Dec 18 11:54:06.611: ISDN Se0/0/0:15 Q931: Received SETUP callref = 0x8001 call ID = 0x0067 switch = primary-net5 interface = User
*Dec 18 11:54:06.611: ISDN Se0/0/0:15 Q931: extract_redirect_orig_called_ie: IE type redirecting num 2071052200 reason 15 cnt 1 plan 2 type 1 pres 0
*Dec 18 11:54:06.631: ISDN Se0/0/0:15 Q931: TX -> CALL_PROC pd = 8 callref = 0x8001
In this trace the called number 179741 is the last 6 digits of the main number of the new bearer and the bit âtype redirecting num 2071052200â is the actual DDI that has been dialed and redirected. So all 300 DDIs for this customer have a single called number in the case of the PSTN provider redirection, with the actual DDI dialed shown only in the IE. The PSTN provider says this is exactly how it should be and that Cisco equipment should be able to extract the correct DDI out of the IE and send the call to the correct extension.
Does anybody know if Cisco 2811 gateway with c2800nm-spservicesk9-mz.124-20.T IOS on it can do this at all? I have had a look through different IOS commands and parameters but I simply could not find any way to look into IE for the redirected number, ignore the actual called number and replace it with the translated redirected number. Has anybody done this before? Is it possible? Or is the PSTN provider simply bluffing? Any advice will be really appreciated.
Thanks a lot.