This section describes the visibility of a switchover to an
application at each stack level.
Note that the platform can be configured either in Parallel
Engine mode (Active/Active) or in compatible mode (Active/Hot-Standby)
and this may have an effect on the behavior during a switchover.
TCAP API |
 |
Failure of one of the active SS7 stacks is transparent to
the application since the remaining active stacks handle the new
incoming and outgoing messages.This behavior is independent of whether
the platform is in Parallel Engine mode (Active/Active) or compatible
mode (Active/Hot-Standby). It is also independent of whether the
level 3 is MTP3 or M3UA.If one of the active SS7 Stacks handling
the traffic fails, all the TCAP transactions currently being handled
by this stack are aborted, and the TCAP users are notified through
a TC_P_ABORT primitive for each transaction lost. The TCAP user
must reset its local timers and state-machines.
SCCP API |
|
If the application calls the API during a switchover it receives
an API_BUSY message.The application should continue to process normally
(by calling the post-select handler function).This behavior is independent
of whether the platform is in Parallel Engine mode (Active/Active)
or compatible mode (Active/Hot-Standby). It is also independent
of whether the level 3 is MTP3 or M3UA.
MTP3, ISUP,
and TUP APIs |
|
On Top
of an MTP3 Level 3
If the application calls the API during a switchover it receives
an API_BUSY message.The application should continue to process normally
(by calling the post-select handler function).This behavior is independent
of whether the platform is in Parallel Engine mode (Active/Active)
or compatible mode (Active/Hot-Standby).For ISUP and TUP, if one
of the active SS7 Stacks handling the traffic fails, all the call
setups being handled by this stack are aborted.
On Top
of an M3UA Level 3
Failure of one of the active SS7 stacks is transparent to
the user since the remaining active stacks handle the new incoming
and outgoing messages.This behavior is independent of whether the
platform is in Parallel Engine mode (Active/Active) or compatible
mode (Active/Hot-Standby).
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