Q931 Cause Codes

SS7 is the signaling protocol that drives most of todays modern telecom network.   Part of the SS7 protocol is a series of cause codes called ISDN (Q931) or SS7 (ISUP) cause codes.  These are numeric codes that provide information about the call set-up and the termination of a call.  Release causes are generic descriptors, not detailed reports.  Having and knowing these codes is very useful, but it cannot answer all questions about why a call was terminated.