[sr-dev] Call Throttling based on SIP Server

Hello, I've run into a situation where I want to throttle the number concurrent calls proxied by Kamailio based upon the SIP Server through which they are intended to go to the end point. The network diagram is somewhat like - UACs (n) -------> Kamailio (on public IP) ------ > SIP Servers (m) (on public IPs) ------------> UACs or TerminationsGateways So basically, n UACs registered to m SIP Servers via Kamailio (working as a proxy). And now I want to put the limitation on all the concurrent calls going to different SIP Servers. Say for an example, only 100 concurrent calls could be setup for SIP Server 'a' , 50 for SIP Server 'b' so on and so forth. I tried checking the different modules but could not find any clue as to how to achieve this through configuration. Now, I can try tweaking a tad of the code to send '403 Forbidden' message from receive.c (although I am not sure whether this is the correct place to do something like this..) I'd be grateful if somebody can throw light on how to achieve this. Please can someone help on this. -- Warm Regds. MathuRahul