Lucent Technologies 8.2 User Manual

Page of 1707
DEFINITY ECS Release 8.2
Administrator’s Guide  
555-233-506  
Issue 1
April 2000
Features and technical reference 
1559
Transfer — Outgoing Trunk to Outgoing Trunk 
20
Interactions
DCS Trunk Turnaround
OTTOTT increases the set of cases in which DCS Trunk Turnaround may 
be accepted. However, use of OTTOTT in combination with a DCS 
network is strongly discouraged. The following algorithm describes the 
DCS Trunk Turnaround request process.
a. If any party on the call receives a local-dial, busy, intercept, or 
reorder tone, deny turnaround.
b. If any remaining party is an answered station or attendant, accept 
turnaround.
c. If any remaining party is on an incoming trunk, accept turnaround. 
For the purposes of this check, an outgoing DCS trunk that has been 
turned around an odd number of times via a DCS trunk turnaround 
is considered an incoming trunk with disconnect supervision. 
Similarly, an incoming DCS trunk that has been turned around an 
odd number of times is considered an outgoing trunk.
d. If any remaining party is an outgoing trunk administered for 
OTTOTT that has received answer supervision, accept turnaround.
e. If any remaining party is an outgoing DCS trunk, forward the 
turnaround request.
f. Otherwise, deny turnaround.
Incoming Disconnect Supervision
Outside of the U.S., incoming disconnect supervision is a switch capability 
that restricts transfers or conferences for certain incoming trunks. In the 
U.S., all incoming trunks are assumed to provide disconnect supervision. In 
some countries this assumption is not valid, so administer whether or not an 
incoming trunk provides disconnect supervision for each trunk group.
Personal Central Office Lines
Transfer of personal CO lines (PCOLs) is not subject to the normal 
restrictions applied to transfer of other trunks. These transfers are allowed 
since the PCOL appearance remains on one or more stations as a feature 
button. System users must be aware that the DROP button cannot be used 
to disconnect the transferred-to party from the call. Hence, if an outgoing 
PCOL is transferred to an outgoing trunk and neither of the trunks can 
supply a disconnect signal, the two trunks lock up.
QSIG Global Networking
If either call is over an ISDN-PRI trunk administered with Supplementary 
Service Protocol b (QSIG), additional call information may display.