Max Local SIP Port: To configure maximum local sip port for
designated SIP account.
Min Local SIP Port: To configure maximum local sip port for
designated SIP account.
Caller ID Header: To choose Caller ID Header format
Auto Answer: If enabled, incoming call will be answered
automatically.
Provisional Response ACK: 100% reliability for all
provisional messages, this means it will send ACK every time
the IP phone receives a provisional SIP message from SIP
server.
Register with user=phone: If enabled, IP phone will send
user=phone within SIP message.
Anonymous Call: If enabled, R27A will block its information
when calling out.