Network Fragmentation And Auto Fallback - Avaya G250 Maintenance Manual

Table 26: H.248 Link Recovery feature/adjunct interactions (continued)
Feature or adjunct
IP phone shared control
feature
Multiple Level Precedence and
Preemption (MLPP)
No-hold conference
H.323/SIP trunks
Administered connections

Network Fragmentation and Auto Fallback

A likely outcome to an H.248 link recovery scenario is that a network of media gateways and IP
endpoints, initially registered to the primary MGC, may now be registered to a number of
different LSPs in the network. This can be very disruptive in that network capability may be
highly compromised. Resources at various points in the network may be available in only limited
quantities, or not at all.
Description
The MGC does not allow an IP Softphone that is
sharing control of an IP phone to re-register until
the IP phone has re-registered. The MGC
allows an IP Softphone that is sharing control of
a DCP phone to re-register only after the DCP
phone is in service. The IP Softphone is
updated with the MGC's knowledge of the DCP
phone's current button state.
The MGC treats calls that are in a connection
preserved state as routine calls, but is also able
to preempt a connection preserved call when
MLPP is enabled.
The no-hold conference feature allows a user to
initiate and complete a conference call while still
talking to the person on the original call. This
feature does not put a party on soft-hold and no
dial tone or ringing is heard. The original
participants in a call that has invoked the
no-hold conference feature to add in a new
party remain on the call during Connection
Preservation. The new party being dialed using
the no-hold conference feature is dropped
during Connection Preservation.
In general, H.323 and SIP trunks are dropped
when the signalling channel is lost, meaning
that calls on those trunks cannot be preserved.
The new MGC reconstructs administered
connections. Any error message generated due
to the new MGC trying to bring up an
administered connection that is already up are
ignored.
System resets
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