Developed for small businesses, the Cisco SPA8800 IP Telephony Gateway (Figure 1) adapts to the needs of businesses that maintain their own on-premise IP private branch exchange (PBX) or that want to add voice over IP (VoIP) to their legacy time-division multiplexing (TDM) PBX or key system. The SPA8800 can be configured to be a FXO gateway for an Asterisk open source PBX, providing a versatile solution when conditions favor an external device. Powered by industry-leading VoIP technology from Cisco, the SPA8800 is designed with a solid hardware casing and contains many standard features, including four RJ-11 FXS and four FXO ports, a 10/100BASE-T RJ-45 Ethernet interface to connect to either a router or multilayer switch, and an auxiliary port for local administration. The gateway also includes a single multiport RJ-21 50-pin connector, offering an alternative connection choice for FXO and FXS ports when deploying the gateway in varied environments. The SPA8800 features a high level of security by implementing state-of-the-art technologies to provide standards-based encryption protocols (Session Initiation Protocol [SIP] over Transport Layer Security [TLS], Secure Real Time Transport Protocol [SRTP], and HTTPS/SSL). The gateway's provisioning capabilities give service providers a secure mechanism not for only remotely managing the device, but also for installing software upgrades without interrupting service and obtaining performance measurements and troubleshooting information. The Cisco SPA8800 is an affordable IP telephony gateway solution that is ideal for small business environments that have VoIP service and also require a connection to the public switched telephone network (PSTN). It can be used with existing analog telephones and teleconferencing equipment, enabling small business customers to protect and extend their investments. SPA8800 = 4-FXO/4-FXS/1-Ethernet.