Symptoms:

  • Phones will ring with 100,1000, or 10000 as the caller-ID and no one will be on the other end.
  • It could happen just once just like it could happen many times a day, every day.

Log into the phone interface via your browser. This can my found from your handsets on screen network settings.

 

system image

Please disable the Allow IP Call and Enable the Accept SIP Trust Server Only.

 

1. Disable IP Call feature:

IP Call feature allow the SIP phone to make and receive calls by IP address

(Without SIP account)

1.1 Change by WEB UI path: Features->General Information-> Allow IP Call

(A yealink T32G/T38G model cannot support configure it through the web UI)

1.2 Change by Auto provisioning parameter:

# 0-disable; 1-enable; default value is 1 (Enable)

features.direct_ip_call_enable =

2. Enable SIP trust feature:

SIP Trust feature allow the phone to only accept the message from the trusted server for specific account.

2.1 Change by auto provisioning parameter:

# 0-disable; 1-enable; default value is 0 (Disable)

account.X.sip_trust_ctrl =

2.2 Change by web UI path: (only V73 or higher firmware support. for W52p/W56p the firmware should be V80 or above, if the W52p firmware is V73 or below, should change the setting via auto provision): Accept Features->General Information-> SIP Trust Server Only

System Image

Each phone manufacturer will vary for a fix to the problem, but the best starting point is to ensure you always have the latest firmware installed for you phone.