Avaya Communication Manager Administrator's Manual page 434

Managing Data Calls
Administered Connection
Dropping Administered Connections
An AC remains active until one of the following occurs:
•
The AC is changed, disabled, or removed.
•
The time-of-day requirements of a scheduled AC are no longer satisfied.
•
One of the endpoints drops the connection. This could be because of user action (in the case of a
data endpoint), maintenance activity resulting from an endpoint failure, busying out of the
endpoint, or handshake failure. If the endpoints are incompatible, the connection is successful
until handshake failure occurs.
NOTE:
An AC between access endpoints remains connected even if the attached access
equipment fails to handshake.
•
An interruption (for example, facility failure) occurs between the endpoints.
If an AC drops because it was disabled/removed or is no longer due to be active, no action is taken. If an
AC drops because of changed AC attributes, an immediate attempt is made to establish the connection
with the changed attributes if it is still due to be active. Existing entries in the error/alarm log are resolved
if they no longer apply. If handshake failure resulted in the dropping of the connection, in the case of an
AC involving at least one data endpoint, no action is taken for that AC until the change
administered-connection command is executed.
Administered Connections failure: Auto
Restoration and Fast Retry
When an active AC drops prematurely, you must invoke either auto restoration or fast retry to determine
whether auto restoration is attempted for an active AC.
If you option AC for auto restoration and the connection was routed over SDDN trunks, auto restoration
is attempted. During restoration, connections are maintained between the server and both endpoints. In
addition to allowing the active session to be maintained, AC also provides a high level of security by
prohibiting other connections from intervening in active sessions. Auto restoration generally completes
before the 60-second endpoint holdover interval. If auto restoration is successful, the call might be
maintained (no guarantee). The restoration is transparent to the user with the exception of a temporary
disruption of service while restoration is in progress. A successful restoration is reflected by the restored
state on the status AC screen. Although the restoration was successful, the data session may not have
been preserved.
If auto restoration is not active or if the AC is not routed over SDDN trunks, Communication Manager
immediately attempts to reestablish the connection (fast retry). Communication Manager also attempts a
retry if the originating endpoint initiated the drop. With fast retry, connections are not maintained on both
ends. Fast Retry is not attempted for an AC that was last established via fast retry, unless the AC is active
for at least two minutes.
If auto restoration or fast retry fails to restore or reestablish the connection, the call drops and the AC
goes into retry mode. Retry attempts continue, at the administered retry interval, as long as the AC is due
to be active.
434 Administrator's Guide for Avaya Communication Manager
November 2003