A Signaling Protocol is used to identify the state of connection between telephones or VOIP terminals. Signaling protocols include: ALOHA, EDSS1, Dual-tone multi-frequency signaling, H.248, H.323, H.225.0, Jingle, Media Gateway Control Protocol, Megaco, R1, NBAP (Node B Application Part), R2 signalling, Session Initiation Protocol (see SIP), Signaling System No. 5, Signaling System No. 6, Signaling System No. 7 (see SS7), SCCP (Skinny Call Control Protocol), Q.931 and QSIG.