Voice over IP (VoIP) Interface allows all 400-series Emergency Phones to be used over an IP data network. The VOIP-8 integrates seamlessly with existing VoIP phone systems, and supports all major VoIP protocols. Each VOIP-8 accommodates up to eight emergency phones (seven if PTSN/PBX failover is enabled) Ethernet connectivity and full IP compatibility with existing routers and WAN infrastructure. Supports all major VoIP protocols, including H. 323, SIP and SPP. Voice prioritization using industry-standard Differentiated Services Protocal (DiffServ QoS). Echo cancellation and jitter buffer ensure top-quality connection.