<tian00di00 at live.com> writes: > I am reading libss7 source code recently, it seems that libss7 sends FISUs > at the full speed it can reach. Is it the correct way to do this? > > Is there any timer specified by the standard at which FISUs should be sent? As I understand your question and remember the standard, this is correct. FISU (fill-in signalling unit) should be sent when there is no other signal unit available for sending. So the ss7 link is never "idle", which is a difference to how ISDN work I think. This is covered in the Q.703 document. - Kristian.