[Users] Dispatching to and checking for trusted UACs

Hi, I'd like to know how you guys on one hand accomplish the task of dispatching requests to trusted UACs grouped to destination classes (e.g. PSTN GWs, Media servers), and to check if an incoming request is from such a trusted UAC on the other hand. Currently the following possibilities seem to be available: - dispatcher-module: dispatching of outgoing requests based on destination classes using ds_select_dst/ds_next_dst, but no check for trusted incoming requests - lcr-module: dispatching of outgoing requests using load_gws/next_gw and check for incoming requests using from_gw, but no support for destination classes - permission-module: check for trusted incoming requests, but no outgoing dispatching - a combination of dispatcher-module for outgoing requests and manual src-ip matching or permissions-module or lcr-module for checking trusted incoming requests The problem with this is that maintaining these UACs gets unnecessarily complicated because there always has to be maintained two module config files or DB tables. So I'm curious which approaches exist to accomplish this or if one module should be extended to combine these two tasks (e.g. adding destination class support for lcr or incoming src-ip check for dispatcher comes to mind)... Thanks, Andy