... ISDN PRI V5.2 signaling and SIP protocol; Advantage:1. Modular design (Two modules, Each module supports maxima ... and A-Law, G.711 Appendix 1, G.723.1 and G.723.1 Annex A, G.729 Annex ... party number translation, second stage dialing, Auto dialing with DTMF, Ring Back tone;·Flexible call routing management; ... have 2 independent VoIP modules;·Each Module contains:-1~4 E1;-128 G.711 Channels;-64 G. ...