Aastra SIP 480i, Administrator'S Manual, Page: 104 / 504

Advanced Network Settings
4-48 41-001129-00 Rev 09, Release 1.4.1
IP Phone Administrator Guide
Configuring the IP Phones
.
Aastra Web UI
Step Action
1 Click on Advanced Settings->Global SIP->Advanced SIP Settings.
2 Enable the " Explicit MWI Subscription " field by checking the check box.
(Disable this field by unchecking the check box).
If the IP phone has a message waiting subscription with the Service Provider, a Message Waiting
Indicator (MWI) (LED or display icon) tells the user there is a message on the IP Phone.
3 If you enable the “Explicit MWI Subscription” field, then in the “ Explicit MWI Subscription Period ”
field, enter the requested duration, in seconds, before the MWI subscription times out. The phone
re-subscribes to MWI before the subscription period ends. Default is 86400.
4 In the " Session Timer " field, enter the time, in seconds, that the IP phone uses to send periodic
re- INVITE requests to keep a session alive. The proxy uses these re- INVITE requests to maintain the
status' of the connected sessions. See RFC4028 for details.