Mitel 6867i Administrator's Manual page 217

• The ability to support SIP outbound on all connection types.
• The ability to configure the SIP outbound keep alive timer.
• The ability to reestablish failed outbound connections in the background.
• The ability to support the DNS Cache Time-to-Live (TTL) requirements
Using this feature depends on the SIP network settings on your phone. The following table
identifies network configuration scenarios, and the method by which this specific feature works
in each scenario.
IF
SIP OUTBOUND DISABLED AND
backup proxy and backup registrar
configured,
backup proxy, backup registrar, and
backup outbound proxy configured,
backup outbound proxy configured
only,
THEN
• All invite, register, and subscribe requests attempt to use
the primary proxy/registrar first
• If the primary registrar fails, the phone registers to the
backup proxy.
• If the backup proxy fails, the phone registers using the
Address of Record (AOR) of the backup proxy, and moves
all subscriptions to the backup proxy.
• When the primary registrar comes back online, the phone
registers to it using the currently active AOR.
• When the primary proxy comes back online the phone
registers with the primary AOR to the currently active
registrar and moves all subscriptions to the primary proxy.
• All invite, register, and subscribe requests attempt to use
the primary proxy/registrar first.
• If any connection fails, the phone registers the backup
AOR on the backup registrar. It moves all subscriptions to
the backup proxy.
• When the primary is functional again, registration and
subscriptions are moved back to the primary
proxy/registrar.
• All invite, register and subscribe requests are sent
through the primary outbound proxy first.
• If the primary proxy fails, the phone performs registration
and subscriptions through the backup outbound proxy.
• When the primary proxy comes back online, the
registrations and subscriptions are performed again
through the primary outbound proxy.
Global SIP Settings
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