Mitel 6800 Series, Administrator'S Manual, Page: 607 / 1113

Advanced Operational Features
6-18
1.
Click on
Advanced Settings->Global SIP->Advanced SIP Settings
2.
In the “
Blacklist Duration
” field, specify the length of time, in seconds, that a failed server
remains on the server blacklist. The IP phone avoids sending a SIP message to a failed
server (if another server is available) for this amount of time. Valid values are 0 to 9999999.
Default is 300 seconds (5 minutes).
For example:
600
3.
Click
Save Settings
to save your changes.
WHITELIST PROXY
To protect your IP phone network, you can configure a “
Whitelist Proxy
” feature that screens
incoming call requests received by the IP phones. 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.
The whitelist is dynamically updated (i.e. the phones are able to refresh and resync the whitelist
[without a reboot] if the IP addresses corresponding to the proxy FQDNs are changed on the
DNS server).
The IP phone monitors the following events and an update is triggered if required:
Note:
The value of “
0
” disables the blacklist feature.