Grandstream UCM6510 innovative IP PBX appliance/n- 1GHz quad-core Cortex A9 application processor, large memory (1GB DDR3 RAM, 32GB Flash) and dedicated high performance multi-core DSP array for advanced voice processing- 1 integrated T1/E1/J1 interface, 2 PSTN trunk FXO ports, 2 analog telephone/Fax FXS ports with lifeline capability in case of power outage - Supports up to 2,000 users, 200 concurrent calls, and 64 simultaneous conference attendees Hardware DSP based 128ms-tail-length carrier-grade line echo cancellation (LEC), hardware based caller ID/call progress tone and smart automated impendance matching for various countries- Gigabit network port(s) with integrated PoE, USB, SD card; integrated NAT router with advanced QoS support