Possible to Receive Redirected Number and Original Calling Number from External (PSTN) Redirect

[User398893]

Hello,

I'm new to this but I'll try to use the right terminology:

A --PSTN--> B --Redirect A over PSTN--> C (Our gateway)

We have multiple callers (A) contacting our supplies (B) who sometimes redirect the original callers (A) to us (C). This all occurs over PSTN lines. When we receive a redirected call, we want to know the original caller's (A) phone number as well as the phone number from which they were redirected (B). Before asking our suppliers to make changes to their phone systems, I wanted to ask here: Is it technically feasible to capture both pieces of information from an incoming PSTN call? If so, how?

Thanks in advance for your help!

[Nithin Eluvathingal]

PSTN network is out of our control. If your PSTN provide calling information as B, there is nothing we can do.

check if your ISP provide redirecting information using debugs on your gateway.

[Elliot Dierksen]

If (big if) your provider sends you that info, you can accept with this command by entering this on the serial interface that represents the D channel (like Serial 0/0/0:23).

isdn incoming ie redirecting-selection last

[User398893]

Thanks Elliot. Assuming our provider can send that info, what configuration, if any, would need to occur on our suppliers side to pass that information?

[Elliot Dierksen]

Every step (end user or provider) along the way has to be configured to send redirecting information. That is it, but that can be challenging depending on how many service providers the call traverses.

[Elliot Dierksen]

It depends on what they are. In a Cisco gateway where the D channel is handled locally, it passes that information by default. In CUCM, there are check boxes for whether redirecting information is passed outbound or received inbound (separate checkbox for each). In your gateway, "debug isdn q931" will tell you if/when you receive it.