Hide call metadata in ISDN call

Hi everyone!

I have two sites which should be merged to one phone network. One site has DID ISDN BRIs and the other side has a standard ISDN BRI without DID.
Both sites have limited IP bandwith aviable, but enough B-channels, so I’ld prefer using POTS as a transport between both sites.

Is it possible to hide a short piece of call metadata somewhere in the signalling part of a call?

For example: The DID site receives a call from 12345 for exten 987. This one is forwarded to the other side via ISDN to 998877. DID-Site Asterisk hides the original call data somewhere during the call forwarding and the other Asterisk at the other side decodes the data and sets the DNIS and CALLERID to the original values (12345/987) before Dial()'ing the final phone.

Another idea would be a splitted data transfer: The call metadata is forwarded via IP and the call itself is forwarded via POTS.

Any suggestions?

you might be able to do it using the calling name feature… you could set the calling name on the outbund PRI to whatever string you want… then the asterisk on the other end of that PRI could parse that field and use it for however you like…
-Christopher