SP5211 VoIP PBX System. .Compliant with SIP protocol .Support up to 100 subscribers, and 32 concurrent calls .Call trunking / routing (DID) .Call forward / hold / waiting / transfer / pick-up / conference .CDR (Call Detail Record) & voice mail Compliant with IETF SIP standards Support G.711A/µ-law and G.729 codecs 2 RJ-45 ports of 10/100M for WAN and LAN connections Provide up to 100 subscribers and 13 concurrent calls Register to multiple public service providers Cooperate with FXO gateway to connect to POTS Intelligent incoming / outgoing call routing Support Call forward (Busy, No-Answer and Unconditional) Support call waiting / call hold / call transfer (attended / unattended ) Support call conference Support call pickup and MWI (message waiting indicator) Customizable auto-attendant greeting and ring back tone Support Voice Mail to e-mail Support Caller ID and Music On Hold Do Not Disturb (SP5101 only) Support Call Monitor Support CDR Support Call Routing