Hi, I have a few questions that I have been researching for a while. Sorry if it is a bit long winded? I have a huge need for VAD and CNG support in Asterisk, as my bandwith is *very * limited and expensive, and VAD, CNG and DTX will save me alot, at least 30 - 50%. I have installed and am using the SVN-bweschke-bug_5374-r9733, which adds VAD and silence suppression support to Asterisk. However, my understanding(and i am hoping people will correct me) is that VAD and CNG is based on the codec being used, so if g723 is being used, it will detect silence, and the codec will set a silence tag, which will tell asterisk this is silence, so generate comfort noise. So all of this will work if both endpoints of a particular call is using SIP with g723(for example). However,if one or both of the voice endpoints are ZAP, will CNG and VAD still be possible.? My topology is an Asterisk with an E1, calls come into the E1 from a PBX, and then get trunked to another Asterisk box, then go out on that E1. And since ZAP is analogue, is it possible for it to support silence suppresion and VAD? So, my question again, is silence suppresion possible when ZAP is involved I would greatly appreciate any pointers/suggestions. thanks, yusuf