Inbound Call Routing on SRST

[shonky10]

I'm looking at installing a centralised SIP solution across Europe, with PSTN backup (local ISDN breakout).

My smaller offices will have SRST.

My question is will inbound calls still be routed to my offices when they are in SRST with no central SIP connection?

 

[trvlr1]

You will have to have some arrangement to route calls via the backup ISDN lines when the network is down.
If you are having ISDN lines there anyway, why not have them live, with DID numbers so external callers can get in without using your network bandwidth up, should be easy to set up an auto reroute for internal corporate calls to work over the network when it is working but reroute to the PSTN when its not.