``showusers'' command

You should send command ``showusers'' and you will receive device with ip and name and users on this device with username, port, phone_from/phone_to and ip address.

showusers 

#: Begin

#: Device 192.168.113.21(vgw) 

501 Serial1/0:31 74212322311/74212323794 0.0.0.0 

#: Device 192.168.113.15(vgk) 

#: Device 192.168.113.28(as01) 

#: Device 192.168.113.12(as02)

#: End

All spaces here - this is TAB (\t) symbol. Every string ended by ``\r\n''.