Aastra SIP 53I Administrator's Manual page 185

Configuring Network and Session Initiation Protocol (SIP) Features
Global SIP Settings
Aastra Web UI
Step Action
2 Enable the "Explicit MWI Subscription" field by checking the check box.
(Disable this field by unchecking the check box. Default is disabled).
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 Enable the "Missed Call Summary Subscription" field by checking the check box.
(Disable this field by unchecking the check box. Default is disabled).
This feature allows missed calls that have been redirected by the server, to be incremented in the
missed calls indicator on the phone it was initially directed to. For more information about this feature,
see Chapter 6, "Configuring Advanced Operational
Note: The "Missed Call Summary Subscription" feature is configurable on a global or per-line basis.
5 If you enable the "Missed Call Summary Subscription" field, then in the "Missed Call Summary
Subscription Period" field, enter the amount of time, in seconds, that the phone uses the Missed
Calls Summary Subscription feature. Default is 86400.
For more information about this feature, see
Features."
Note: The "Missed Call Summary Subscription Period" is configurable on a global basis only.
6 Enable the "Send MAC Address in REGISTER Message" and the "Send Line Number in
REGISTER Message" fields by checking the check boxes.
(Disable these fields by unchecking the check boxes. Default is disabled for both fields).
For more information about these message features, see
Operational Features.".
7 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.
8 In the "Timer 1 and Timer 2" fields, enter a time, in milliseconds, that will apply to an IP phone
session. These timers are SIP transaction layer timers defined in RFC 3261.
Timer 1 is an estimate of the round-trip time (RTT). Default is 500 msec.
Timer 2 represents the amount of time a non-INVITE server transaction takes to respond to a
request. Default is 4 seconds.
41-001160-00, Release 2.1, Rev 04
Features.".
Chapter 6, "Configuring Advanced Operational
Chapter 6, "Configuring Advanced
4-61