Aastra SIP 53I Administrator's Manual page 187

Configuring Network and Session Initiation Protocol (SIP) Features
Global SIP Settings
Aastra Web UI
Step Action
16 (For Broadsoft Servers) The "Blacklist Duration" field is enabled by default with a value of 300
seconds (5 minutes). Valid values are 0 to 9999999.
This feature sets the time period, in seconds, that the IP phone resubscribes the BLF subscription
service after a software/firmware upgrade or after a reboot of the IP phone.
Note: The value of "0" disables the blacklist feature.
For information about setting the "Blacklist Duration", see Chapter 6, the section,
(Broadsoft Servers)"
17 Enable the "Whitelist Proxy" field by checking the check box.
(Disable this field by unchecking the check box. Default is disabled).
When this feature is enabled, an IP phone accepts call requests from a trusted proxy server only. The
IP phone rejects any call requests from an untrusted proxy server.
For information about setting the "Whitelist Proxy", see Chapter 6, the section,
page 6-19.
18 Click
41-001160-00, Release 2.1, Rev 04
on page 6-17.
to save your changes.
"Blacklist Duration
"Whitelist Proxy" on
4-63