Lucent Technologies MERLIN LEGEND Release 6.1 System Planning Manual page 106

MERLIN LEGENDCommunications System Release 6.1
System Planning 555-661-112
3 Lines/Trunks
Selecting Line/Trunk Options
Loop-Start Reliable Disconnect
Disconnect signals on incoming calls on loop-start trunks are classified as one of
the following:
Reliable. A disconnect signal is sent to the system by the local telephone
company shortly after a caller hangs up. Loop-start trunks must be reliable
for remote call forwarding and trunk-to-trunk transfer. Also, reliable
disconnect is strongly recommended for remote call transfers, and VMSs
such as MERLIN LEGEND Mail.
Unreliable. A disconnect signal is not sent by the local telephone company
on every call.
!
SecurityAlert:
Toll fraud can occur when loop-start lines/trunks are used with unreliable
disconnect. If the calling party stays on the line after the called party hangs
up, the central office will return a dial tone at the conclusion of the call
enabling the caller to place another call as if it were being placed from your
company.
Since the disconnect signal on most loop-start trunks is unreliable, the factory
setting for the disconnect signal is Unreliable.
Before you change the setting, check with the telephone company to determine
whether the disconnect signals for the loop-start trunks are reliable and to obtain
the length of the hold disconnect interval.
If you select Reliable disconnect, you can set the interval after which the line/trunk
is released as described in "Hold Disconnect Interval" later in this section.
Trunk-to-trunk transfer is programmed on a per-extension basis and should
remain disabled even if the loop-start trunk has reliable disconnect. See the
"Trunk-to-Trunk Transfer" section in Chapter 4.
Planning Form Instructions
At the top of Form 2c, under the Loop-Start Reliable Disconnect heading, choose
one of the following:
If the loop-start trunks have an unreliable disconnect signal, check the No
box (the factory setting).
If the loop-start trunks have a reliable disconnect signal, check Yes.
NOTE:
If the local telephone company uses a short hold disconnect interval,
do not specify a reliable disconnect signal. Also, to ensure proper
voice messaging operation, and for private network systems, the
system must have ground-start or loop-start trunks with reliable
disconnect.
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Issue 1
August 1998
Page 3-12
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