Patrick, Those where 2 very good links - you don't accidentally know about a MAP, CAMEL or INAP protocol in open source as well? I notice that these SIGTRAN/SS7 protocols are LGPL so we could actually use them in FreeSWITCH. Is anyone doing work in this area? Jan --- I am not aware of one Open Source project that does all you are looking for. OpenBSC (http://openbsc.osmocom.org/trac/) seems to come close (MSC, BSC, AUC, HLR, VLR, EIR). Kannel (www.kannel.org) might be some piece of the SMSC puzzle and for SIGTRAN Mobicents-SS7 seems to fit the bill: http://www.mobicents.org/ss7/intro.html If you are going the TDM route too then Sangoma has excellent TDM cards (and hardware EC cards) and they are supported by Mobicents Have fun integrating all the parts. Seems like a fun job :) Regards, Patrick