Every once in a while we have an incoming calling issue (TDM side of the house) where we need to talk to our tandem to find out which trunk of theirs the call came in on. Most of the time we have to do that while the call is in progress, or wait till it comes in again so they have their SS7 analyzer ready. A person in our company heard from another telco who uses another tandem that it's possible for us not to involve our tandem, but discover/learn at least some part of the call path using SS7, that is, be able to see beyond our tandem. Our tandem says that's not possible, but our person says the other telco is sure about this. Anyone know either which way? Frank