1)A single module with 2 E1; 2)Support SIP, H323, SS7, PRI; 3)Locates on ... between SS7(ISDN PRI, CAS, V5.2 ) and SIP protocol transform. as well as media transfers between the PSTN and ... series) -ISDN-PRI(ITU-T Q.931,Q.921) -V5.2(ITU-T G.964, G.965)·VoIP protocol support: -SIP(RFC3261, ... RFC3362(T.38), RFC2833(DTMF)); -Code: ...