HPE VCX V71xx Gateway Series Voice over IP gateways help enterprises transition to IP communications using a cost-effective strategy that aligns financial considerations with performance needs. The gateways lay the foundation for a successful deployment of Session Initiation Protocol (SIP)-based applications, and enable interoperability between a converged IP network and legacy equipment-including PBXs, the public switched telephone network (PSTN), analog phones, and fax machines. The HPE VCX V7122 digital gateways provide all necessary functions and protocol support for handling voice calls between traditional circuit-switched phone networks and an IP network. HPE VCX V7111 analog gateways (both FXS and FXO models) let analog phones and other legacy analog devices use HPE SIP-based IP telephony features-an especially helpful feature during transitions, enabling employees to continue using familiar equipment and interfaces, including dialing plans, email systems, fax machines, and modems.