The economical Zoom Model 5801 & Model 5802 Voice over IP Telephone Adapters allow standard analog telephones to make & receive calls over a broadband Internet connection. Simply plug a conventional or cordless phone into the adapter & then plug the telephone adapter into a broadb&-connected router or Internet gateway. Up to five & often more attached phones can be rung simultaneously using the built-in ring generator. The Model 5801 & Model 5802 support industry-standard Session Initiation Protocol (SIPv 2) & work with a wide range of service providers & SIP-based Vo IP equipment. Both models provide one FXS & one FXO port & allow calls to be bridged between the Public Switched Telephone Network (PSTN) & Voice Over IP. The FXO port of the adapters also include the Tele Port™, an intelligent relay that allows a single phone to place & receive both Vo IP calls & calls over the PSTN. PSTN fail-over allows the 5801 & 5802 to automatically route calls over the dial-up phone network when power is lost. PSTN support also allows emergency dialing using services like 911, 112, or 999 calling. PSTN to Vo IP call bridging with security is provided, as well as Vo IP to PSTN call bridging. Voice over IP Service providers can deliver a rich variety of advanced telephone services through the Model 5801 or 5802 including CLASS features such as Call Waiting, Caller Identification, Call Transfer, Call Hold, Call Forwarding, Distinctive Ringing, & Voice Message Waiting Indication. The Vo IP telephone adapters can be configured remotely using a TFTP or HTTP download from the service provider & updates to the firmware can be automatically delivered. Local configuration is done with a browser-based graphical user interface. The Model 5801 supports G.711, i LBC & G.729 voice codecs. The Model 5802 supports G.711 & i LBC. Both units are built & supported by Zoom Technologies, a publicly traded company (NASDAQ:ZOOM) with over 29 years of experience in telephony & data communications.