ATT DEFINITY Communications System Generic 3 Instructions Manual

Network Services
Issue  3   March 1996
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Electronic Tandem Network (ETN)
An Electronic Tandem Network (ETN) is a hierarchical network of privately owned 
trunk and switching facilities that can provide a cost-effective alternative to toll 
calling between locations. An ETN consists of tandem switches, the intertandem 
tie trunks that interconnect them, the access or bypass tie trunks from a tandem 
switch to a main switch, and the capa bility to control call routing over these 
facilities. A...

Functional Description
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Refer to the System Parameters table In Appendix A for the node limitations of 
each system type.
An attribute of a DCS configuration that  distinguishes it from other networks is 
that it appears as a single switch with respect to certain features. This provides 
simplified dialing procedures between locations, as well as the convenience of 
using some of the system’s features between locations. DCS is particularly useful 
if there is frequent...

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Issue  3   March 1996
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Figure 2-6. Typical Distributed Communications System
Some voice features have transparency in a DCS configuration. The following 
voice features have unique aspects in a DCS environment and are d esc rib e d in 
detail in this book.
nDCS Alphanumeric Display for Terminals
nDCS Attendant Call Waiting (described under DCS Call Waiting)
nDCS Attendant Control of Trunk Group Ac cess
nDCS Attendant Direct Trunk Group Selection
nDCS Attendant Display
nDCS Automatic...

Functional Description
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nDCS Call Forward ing All Calls
nDCS Call Waiting — Termination (described under DCS Call Waiting)
nDCS Distinctive Ringing
nDCS Leave Word Calling
nDCS Multi-Appearance Conference/Transfer
nDCS Priority Calling (described under DCS Call Waiting)
nDCS Trunk Group Busy/Warning Indication.
nEnhanced DCS (described under Enhanced DCS).
Abbreviated Dialing and Last Numb er Dialed also have transparency in a DCS 
configuration. These features o perate the same...

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Issue  3   March 1996
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remote systems. DCS Call Coverage provides transparenc y across systems for 
the Call Coverage feature.
Main/Satellite/Tributary
Figure 2-7 shows a Main/Satellite/Tributary configuration. It can function 
independently or serve as an ETN access arrangement. For a Main/Satellite 
configuration, attendant positions and public network trunk facilities are 
concentrated at the Main, and calls to or from satellite locations pass through the 
Main. To a caller...

Functional Description
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Trunking
Trunking is the use of communications links to interconnect two switching 
systems, such as connecting the switch to a local central office or to another 
switch. These links, called trunks, can be grouped together in Trunk Groups 
when all the trunks in the group perform the same function. This g rouping 
simplifies administration since the required service characteristics (parameters) 
are assigned to the group rather than to each trunk....

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— a Private Branch Exc hange  (PBX)
— an ETN switc h
— an EPSCS or Common Control Switching Arrangement (CCSA) 
office
— MEGACOM Service (AT&T unbanded long distance service.)
nWATS —Provides access to a portion of the DDD network via d e dicated 
trunks to a WATS serving office.  Each WATS trunk terminates as a WATS 
line in the WATS serving office.  The trunks used are always one-way 
outgoing. Outgoing WATS calls to various geographic areas are ma de on 
an...

Functional Description
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nImmediate Start — No start dial signals are used. On outgoing  calls, the 
system waits at least 80 milliseconds (a configurable amount of time) after 
sending the seizure signal b efore sending the digits required at the d istant 
switch. This gives the distant switch enough time to attach a digit receiver 
to the call.
nWink Start — A momentary signal (wink) is sent to the distant switc h when 
the trunk is ready to receive digits.
nDelay Dial — A...

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‘‘answered’’ when answer supervision is returned from the far end or when 
answer supervision time-out expires. Also, if there is a trunk incoming from one of 
the previously listed offices on a call of this type, then answer supervision is sent 
to that office. An incoming call to a Direct Department Calling (DDC) or Uniform 
Call Distribution (UCD) recorded delay announcement is deemed ‘‘answered’’ 
when the calling party is connected to the announcement....

Functional Description
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System Management
System Management provides the capabilities to control and maintain the system 
and also provides system usage reports to help determine if the system is being 
used as intended. In short, System Management allows the System Manager to 
establish the system, monitor its use, and make additions and/or changes as 
necessary. System management d evices are the Generic 3 Management 
Terminal (G3-MT) or the Generic 3 Management Adjunct...