The Med's BT Abbreviation Guide
The following is a list of abbrevations and their descriptions, the file
is
not finished in any respects and I shall be updating it in the future..
at
the moment, in only deals with the System X switch (`SYS-X') because i
don`t
have enough infomation on AXE10 to compile much about that.
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AAR Automatic Alternative Routing.
AAS S-X Automatic Announcment Subsystem. Not used in trunk exchanges
because it is done by the SIS in a trunk exchange. In a local
exchange it provides the recorded announcements (`Voice Guidance')
whilst the DS3 provides the tones.
ACP Access Control Pair.
AEQ Automatic Announcement Equiptment.
AIR Alarm Interface Controller
AJG Analogue Junctions Group.
ALE Analogue Local Exchange
APT Alarm Port.
ARAB TXE Alarm Reset And Busy
ARR Automatic Re-Routing.
ARU TXE Alarm Reporting Unit
ASU Advanced Services Unit - FNET (Feature Net).
ATE Automatic Telephone Exchange.
AUS S-X Access Utility Subsystem.
AXS Auxiliary Supervisor
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CAB Cable Box, the green things at the end of each road.. with
everyone's lines in.
CAS S-X Call Accounting Subsystem. Uses the caller infomation to charge
the subscriber for a call and then increments the callers record
table. (the record table is a software version of the subscribers
meter)
CPS S-X Call Processing Subsystem
CCR Concentrator.
CCS Call Connect System.
CCU Colocated Concentrator Unit.
CCR Concentrator
CCX Concentrator Extra Parameter
CNI Calling Number Interception.
COMFORTE COMputers FOR Telephone Exchanges.
COW Clerk Of Work
CPS S-X Call Processing Subsystem. The functions of the CPS in the local
exchange is the same as it would be on a trunk exchange. It has
overall control over any call. It registers the state of line
from the subscriber (busy/free etc..), Stores class of Service
(0out going barred, incoming barred etc..), controls the star
facilities, controls time outs and communicates with other
software such as the call accounting subsystem.
CSB Central Site Processor
CSO Contract Supervising Officer.
CSO Centralized Service Observation
CSS Customer Services And Systems.
CUG Closed User Group.
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DAM S-X Alarm Monitor
DCD Data Compiler/Decompiler.
DCD LOOP The process of Decompiling data and feeding the output in as the
input to the compiler.
DCCE S-X Digital Cell Center. This is an exchange that :
a) Provides service to its own customers and act as parent for
RCUs.
b) Act as a parent for analogue exchanges, terminating analogue
line plant and performing call charge as required.
c) Concentrate and foward traffic to the DMSU for parented
Analogue Local Exchanges (ALE) without their own DMSU links.
d) Switch Tandem Traffic Between other DLSUs.
DDC District Data Center
DDT Digital Line Termination
DDSN Digitally Derived Services Network. (0800, 0891 etc...)
DJSU S-X Digital Junction Switching Unit. This is a switching unit in a
high telephone density local network which performs a tandem
switching function, but has no customer connections.
DLS S-X Digital Local Switching Unit. General term for Digital Local
Processor Exhchange. It provides service for it's customers.
It can also provide other facilities dependaent on it's role as
either a DCCE or DLE.
DLE Digital Local Exchange. This is a DLSU which may host RCUs as in
a) for DCCEs and also act as a parent for those ALEs which will
be replaced by RSUs parented upon the DLE as in b) and c) of
DCCEs.
DLT Digital Line Termination
DMS100 Digital Multiplexor Switch, make by AT&T Bell, and used in England
as an International Gateway Exchange.
DMSU S-X Digital Main Switching Unit. Provides a fully interconencted Trunk
Network. Each DMSU catchment area will compromise of several old
GSC areas. The DMSU will switch traffic bother between and within
the catchment area.
DMU Dialled Meter Unit.
DN Directory Number
DPC Destination Point Code
DPLE Digital Principle Local Exchange. Main exchange for an area.
DS3 Digital Subscribers Switching Subsystem. This is in principle the
same as the RCU yet it is situated inside the exchange - both are
usually called subscontractors. It is used to connect subscribers
to the local exchange. They are connected via PCM links.
DSG District Support Group (BT District Staf)
DSS S-X Digital Switch Subsystem. The DSS carries out all the switching
functions on a System X exchange - Trunk or local.
DSSS S-X Digital Subscribers Switching Subsystem. See DS3.
DSW D-Switch
DWI Display Work Instructions - A common found trash.
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EBP Exchange Based Processor
ECTE Exchange Terminal Computer Equiptment
ERS Emergency Repair Service
EL Exchange Log
EN Equipment Number
END Exchange name documentation
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FNET FeatureNet.
FMR FaultMan's Ringback. Dial the FMR (3 digit starting with 1 -
generally 17x) number and replace handset, upon ringback the
service should provide a quick analysis of any problems.
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GP Global Profile
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HTD Hardware trial period.
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I/C Incoming
IDDF Intermediate Digital Distribution Frame
ISDN Intergrated Services Digital Network.
ISIS Inland Services Infomation System. ISIS is basically a book and
manual service. Within ISIS it is possible to find infomation
through indexing. Coding is AAA/BBB/Cxxx. AAA = Discipline,
BBB = Main Subject, C = Tertiary Function/Specialism,
xxx = document number.
AAA - listing approx 30 disciplines eg, Personal, Transmission,
Operator Services, Customer Services etc..
BBB - Listing approx 150 main subjects within the respective
disiplines eg Employment, Optical Fibre systems, Operating
procedures etc..
C - Listing approx 500 functions of specialisms within their
respective main subjects. E.g Recruitment, Planning &
Implentation etc..
EXAMPLE = CSS/CCS/C010.. installation practice for mini master 3
ISOS In Service Operational Support (Manufactures Staff). The ISOS
would be called in when an urgent problem needs a higher level of
support, or if a major service failure occours they can be called
in quicker than the PSG.
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JAX S-X Junction Circuit Auxiliary
JCA S-X Junction Circuit Auxiliary
JGX S-X Junction General Purpose Auxiliary
JSW S-X Junction Q Switch
JUN S-X Junction Subscriber
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LAN Local Area Network
LAP Local Access Point
LCG Line Controller Group
LCN Line Controller Number
LID LAN Interface Device
LLE Large Local Exchange.
LNE Subscriber Line
LNO London Network Operations
LPT Local Control Point Port
LUN Line Unit
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MAIU Meter Alarm & Interface Unit
MCO Maintenance Clearence Officer. OMU worked responsible for making
sure all tasks and routines have been carried out.
MCS S-X Maintenance Control Subsystem. Carries out maintenance functions.
MDF Main Distribution Frame
MED Possibly the best H^P group in the world. :)
MEER Miscellaneous Electronic Equiptment Rack
MFX MF4 Test Auxiliary Board
MLE Medium Local Exchange.
MMI Man-Machine Interface
MMIS Man-Machine Interface Subsystem. The MMIS allows engineers to
control and manage the exchange through VDT's etc..
MML Man-Machine Language
MOJ Metering Over Junction
MPCS Multi Party Connection Subsystem. The MPCS allows 3>10 subscribers
to be connected together at the same time.
MPR Microprocessor
MRA Malfunction Reporting Alarm
MSS Management Statistic Subsystem. Keeps records of the junction
routes in the local exchange and keeps traffic records for DS3s
and RCUs under it's control and also for the AAS.
MTS S-X Message Transmission Subsystem. Terminal part of CCS (not to be
confused with CSS) link. It transmits and recieves messages sent
between distanct CPSs (Call Processing Subsystems) and carriers
out error checks on messages and re-transmits if necessary.
MTS(MsgFor)The MTS message format is : - Error Check, Message, Routing
label,
header. The header contains the message number incase a resend is
needed, the routing label includes the OPC (Originating Point
Code) which identifys the originating exchange and the
Destination Point Code (DPE) which identifies the destination
exchange. The message tells CPS what it has to do and the error
check obviously checks the message for errors.
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NAC Number Area Code
NIC Network Interlock Code
NSS Network Synchronisaton Facility
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O&M S-X Operations & Maintenance, look out for these (big!) folders
in a
sys-x exchange.
O/G Outgoing
OIM Operation & Maintenance
OCB Outgoing Calls Barred
OMC Operations & Maintenance Center. BT policy requires this, collects
data from exchanges and monitors data for presentation for the
OMC staff (Traffic, Sales, Operation & Maintenance Unit. (OMU) )
OMU Operation and Maintenance Unit. Room where engineers moniter the
performance of the exchanges, and recieve data collected my the
OMC. There is one or more connected to each OMC. OMU staff can
send data to the OMC to control the exchanges conneted to it.
OOS Out Of Service
OUC Organisational Unit Code
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PABX Private Automatic Branch Exchange
PACE Plessey Automatic Commisioning Equiptment
PATE4 Print Analysis - TXE4
PBX Private Branch Exchange
PCM Pulse Code Modulation
PCM links A maximum of 30 channel PCM systems coontect to the DSS which
gives 240 speech channels (8x30) which are available to 2048
subscribers.
PCS Subscriber's Private Circuit
PDN Private Data Network
PFT Pass Fail Thresholds
PLEXUS/SDF Computer center with both ICL and PLEXUS systems
PRAT Primary rate access terminal
POE Path Of Entry
TPOE Translation Point Of Entry
PSG Product Support Group (BT Headquarters Staff). PSGs can be called
in if there is a problem on site. They give the authority for any
emergency design modifications carried out without authority
having being gained in advance.
PSN Packet Switched Network
PSTN Public Switched Telephone Network - The standard telephone service
PSU Power Supply Unit
PUS2 The Central Processor which provideds the processing power and
storage facilites for all other subsystems.
PXSM Pre-Extension Site meeting
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QSU Q-Switch
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RAD Resistance Adjustment
RALP Remote Alarm lamp panel.
RATES Remote Access Test Equiptment System.
RCC Remote Concentrator Centre. Point with many RCU's.
REMT Remote.
RMCC S-X Remote Multi-Concentrator Unit. Two or more subscribers connected
in a RCC.
RCU Remote Concentrator Units. These must be connected to the DLSU and
are considered as part of the DLSU to which they are connected.
The RCU is situated away from the Telecom building in a more
convienient place and it is the apparatus that divides the lines
and gives them their equiptment numbers. If there is no
connection between the RSU and the exchange then customers may
still call numbers controlled by the RSU but not outside. Charge
Handling is handled at the TE so if there is no connection to
the TE there is no call charge. Telecom uses a standard two RCUs
for security reasons.
RFA Ringer Fuse Alarm
RTU Remote Terminal Unit
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SAC Service Address Code
SADIE TXE Subscriber Automatic DIsconnect Equitment. Used to place
subscribers apparatus TOS (Temporalily Out Of Service).
SALT Subscribers Automatic Line Testing. For System X and Y exchanges.
The code for this is generally 175 and has the same job as the
FaultsMans Ringback but is more advanced with increased options
after the ringback.
SBR S-X ENS Exchange Subscriber
SDP System data page
SPM Customer's Private Meter
SPU S-X Speech Interworking Unit.
SIS S-X Signalling Interworking Subsystem. Used as an interface between
a
System-X exchange and analogue exchanges. It convers analogue to
30 channel PCM for connection to the DSS. In like local exchange,
unlike to trunk exchange it does not send tones or annoucments -
the AAS does.
SIU Slide-In-Unit
STX Substitution Auxiliary
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TAC S-X Test Access Console
TCC Through Connected Circuit .
TE Telephone Exchange/Terminating Equipment.
TID Terminal Identity.
THW DSSS Test Highway
TKO TrunK Offering
TNC S-X Test Network Controller.
TNET Tymnet
TNS S-X Test Network Subsystem. The TNS controls the accessing of and
testing of all digital and analogue junctions and subcriber lines.
It uses SIS to access analogue junction lines, DSS to access
digital junctions and DS3 tto access subscribers lines.
TOC Type Of Circuit Digits
TOS Temporalily Out of Service
TNC Test Network Controller
TNO Test Network Operations
TPN Telephony Process Number
TSVC Telephone Service and Vechicle Centre
TXD #'s A method of labeling types of exchange by number that forms part
of the exchange's Network Nodal Identity which appears on all
documents specific to the particular exchange.
TXD NO EXCHANGE
3 RCU (System X)
5 UXD5
6-9 DLSU (System X)
13 DMSU
14 DJSU
30 OSSU
31 OCHC
53 RSU (AXE 10 (System Y))
56-59 DLSU (AXE 10 (System Y))
80-86 OMC
TXE Telephone eXchange Electronic.. most commonly in the form of a
TXE4, or TXE4A (cost reduced).
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UID User Identity
UM Unit Manager. The UM is responsible for the service given by the
TXD exchanges in his OMC area and the organisation of staff.
UXC Utilities Card
UXD5 Digital Exchange developed from the CDSS1 (Monarch) PABX.
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VMB Voice Mailbox
VRS Voice Response System. Allows remote testing of subscriber's
line gived number and code. There are possibly other
systems under the heading VMS because it's not exactly
very use specific.
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WMS Work Manager System. Used by BT engineers to download their
infomation for jobs of the day. Generally used via a portable
field terminal and acostic coupler. It is accessable from any
termination point in England.
WN Worldwide Networks
WNI Worldwide Networks Intstruction
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XD ExDirectory.
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