Based on SIP, the Cisco SPA 303 3-Line IP Phone with 2-Port Switch has been tested to help ensure comprehensive interoperability with equipment from voice over IP (VoIP) infrastructure leaders, enabling service providers to quickly roll out competitive, feature-rich services to their customers. With hundreds of features and configurable service parameters, the Cisco SPA 303 addresses the requirements of traditional business users while building on the advantages of IP telephony. Features such as easy station moves and shared line appearances (across local and geographically dispersed locations) are just some of the many advantages of the SPA 303. The Cisco SPA 303 IP phone can also be used with productivity-enhancing features such as VoiceView Express, and Cisco XML applications when interfacing with the Cisco Unified Communications 500 Series in SPCP mode.