Grandstream ucm6302 ip pbx, 1000 users, 150 concurrent calls, 2хfxs, 2xfxo, 1xwan, 1xlan // supports up to 3000 users and up to 450 concurrent calls zero configuration provisioning of grandstream sip endpoints built-in conferencing meetings platform supports desktop, wave app, and sip endpoints wave for android, ios, chrome and firefox browsers allows communication with all ucm6300 users solutions api available for third-party integrations, including crm and pms platforms advanced security protection with secure boot, unique certificate and random default password to protect calls and accounts three gigabit auto-sensing rj45 network ports with integrated poe+ and support nat router automated nat firewall traversal service facilitates secure remote connections supports full-band opus voice codec and h.264/h.263/ h.263+/h.265/vp8 video codec, jitter resilience up to 50% packet loss compatible with gdms for cloud setup, management and monitoring based on asterisk* version 16 open source telephony operating system