For the access to the fixed telephone system to extend the use range.
FEATURES：
1. To connect with PBX telephone switchboard and the public telephone network via the analog phone line.
2. With 1 FXO interface (standard) with options of the 4/8/16 FXO interfaces (for two or more calls);
3. To make a random full-duplex intercom to any IP terminals through the outside line and vise versa.
5. Available for the outside line to broadcast to the IP terminals.
6. With a standard RJ45 port supportive of crossing network segment and router, accessible to the system if the Ethernet is available.
