Mitel 6867i Administrator's Manual page 597

CONFIGURING WHITELIST PROXY USING THE MITEL WEB UI
Use the following procedure to configure the Whitelist Proxy feature using the Mitel Web UI.
MITEL WEB UI
1. Click on Advanced Settings->Global SIP->Advanced SIP Settings
2. The "Whitelist Proxy" field is disabled by default. To enable this field, check the box.
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.
3. Click Save Settings to save your changes.
Advanced Operational Features
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