Central line that supports the cloud system (Grand Stream)

Up to 500 IP users (SIP) and 75 concurrent calls, PSTN Lines FXO port and FXS port for analog phone,
4 video conference rooms and up to 20 parties at 1080p, assuming 4 video channels + 1 screen sharing (H.264 & Opus) Supports audio meeting: up to 75 parties
Automatic detection of Grandstream phones for easy programming
Ports: USB 3.0 * 1 and SD card * 1
Offers API for easy integration with external software
Call features: Call park, Call transfer, Call waiting, Caller ID, Call recording, Call history, Ringtone, IVR, Music on hold, Call tracks, DID, DOD,
DND, DISA, Ring group, Simultaneous ring, Schedule,