VoIP ATA (Analog Terminal Adapter) is a telephone extension to the IP network.  It offers a traditional telephone line (PSTN) interface to an analog telephone, PBX line extension, or a fax machine.  Its WAN port interface allows access to the IP network in order to offer voice and fax services.  It is a great way for turning a traditional PBX to access the low cost VoIP services and for deploying VoIP service by an ISP.   An additional Ethernet port allows broadband connection for the existing PC or other network device without buying additional network equipment.  It is an ideal low cost product for SME and SOHO IP telephony application.