SIP Client Application is the right firmware for your Barix device to integrate it into an existing VOIP phone system. SIP Client works with most SIP based VoIP solutions including Cisco Unified Communications Manager or Asterisk. Using the Session Initiation Protocol (SIP), the client device receives a phone number in addition to its IP address, and can communicate either on a peer-to-peer connection or over a proxy-based connection (PBX). Ringtone and busy tone guarantees that the call remains confidential and the recipient really receives the information. Featuring background music, audio rebroadcasting, priority audio port and special DTMF commands to quickly manage the device, the SIP Client expands the functionality to your SIP system. Even controlling the relays (e.g. to open door) of a Barix device via SIP phone is no problem with this solution.