UCM6202 - USCM6204 - UCM6208
*UCM6202 and UCM6204 support up to 500 users and 50/75 concurrent calls 
*UCM6208 supports up to 800 users and 100 concurrent calls

*Auto Discovery and Zero Configuration of Grandstream SIP endpoints
* Integrated 2/4/8 trunk Lines, 2 analog telephone ports with lifeline capability 
* up to 50 SIP trunk accounts : installed on mobiles
* Gigabit network ports with Integrates PoE, USB, SD card
* Supports up to a 5-level IVR (Interactive Voice Response)
* Built-in call recordings server; recordings accessible via web user interface
* Built-in Call Detail Records (CDR) for tracking phone usage by line, date, etc.
* Supports multi-language auto-attendant and call queue to efficiently handle incoming calls
* Strongest possible security protection using SRTP, TLS and HTTPS encryption
* Supports any SIP video endpoint that uses the H.264, H.263 or H.263+ codecs