Service outage caused by
cutting or damaging fiber optic cable(s).
Cable Entrance Facility - CEF
entrance point for cables into the building, typically where conduits from
the street end. It usually has a framing structure
for the organization of splices and cables.
Name for Tellabs Cablespan 2300
equipment utilized by ELI for dialtone traffic. Comprised of two main parts - the HDT which is located in the HUB and
the RST which is located at the remote customer
location. Equipment muxes and demuxes traffic from the DS-0 level up
to the DS-1 or DS-3 level and then breaks it back
A completed switched communication (at
a specified bandwidth) between two stations on a
network. A call is originated by a "calling party",
"calling station" or "caller". The destination or
termination of a call is the "called
party", "called station(s)" or "destination
node" on the network.
Call Detail Record - CDR
record produced by Switches to track Call Type, Time, Duration, Facilities
used, Originator, Destination, etc. CDRs are
used for customer billing, rate determination, network monitoring, and facility capacity planning. CDRs
represent unrated calls (to be processed by
Rating) in contrast to Tolls, which are rated calls.
The period of time that
begins with Answer Supervision (destination off hook) and ends when
the call is terminated.
Call Processing Data - CPR
to SMS to define specific 800 service features, such as call routing by:
time of day, day of week, state of call
origination, load balancing, etc.
Call Routing Tree
A graphical display
of complex call routing decision logic.
A graphical display of computer
function Call sequence. Documents function usage. Used for change impact analysis.
(e.g. 1+, 0+, 800, etc.)
Called Station - Also known as Called Party Destination Node On The
The telephone number to which a
call is directed or terminated.
A telecommunication credit
card with an AuthCode for using a long distance carrier when the
customer is away from their home or office
Calling Station - Also known as Calling Party - Origination Node On
The telephone number or ANI
that initiates a call.
CAP - Competitive Access Provider
CAPC - Competitive Access Provider Capacity
The highest possible (reliable) transmission speed that can be carried on a
channel, circuit or piece of equipment.
Capacity may be expressed as raw speed or net throughput.
Card Issuer Identifier Code - CIID - (pronounced "sid")
A code issued with certain calling cards.
AT&T's CIID cards cannot be used by other interexchange carriers but can be used by LECs.
A telecommunications provider
which owns switch equipment.
A higher level circuit
(DS-1, DS-3, Transmission System, etc.) that has been designed to carry lower-level circuits (DS-0, DS-1).
Carrier Facility Assignment - CFA
identifier for the Telco network point where an IEC connects.
Carrier Identification Code - CIC
digit number used with Feature Groups B and D to access a particular IEC's
services from a local exchange line.
One or more CIC codes are assigned to each carrier. The ELI CIC is 802, so our customers would dial 1+ 0 + 802,
followed by 1 + area code and phone number he wants
Use of 800 service call
routing features to divide 800 calls between two or more IECs. Split
may be by % allocation, origination NPA, Time
of Day, etc.
A frame relay switch deployed
by ELI in multiple locations, to support the backbone network.
Cascade company in now owned by Ascend
Allow any ANI
(including undefined ANIs) to access a given carrier.
Any person or
organization that dials any CIC Code. (Not necessary to pre subscribe to the
CATV - Community Antenna TeleVision
community television system, served by cable and connected to a common (set
of ) antenna(s). 1994 Federal legislation may
allow them to compete with LECs for telephone service (on the Information Superhighway).
CBR - Constant Bit Rate
An ATM service
category which supports a constant or guaranteed rate to transport services
such as video or voice as well as circuit emulation,
which requires rigorous timing control and
CBUD - Call Before U Dig
Signs often seen
along fiber optic cable routes, which designate an operational management
system for protection of fiber facilities. May
have electronic geographic maps of states, counties
and city streets where the carrier has buried facilities, upon which
reported construction activities are automatically
mapped. Human technicians verify that the activities do not pose a
danger to the facilities, or dispatch on-site
technicians when facilities may be at risk.
CCITT - Consultant Committee on International Telephone and
An international organization which
develops standards and defines interfaces for telecommunications. (now known as ITU).
1) Common Channel Signaling - A method
of digitally transmitting call-setup and network
control data over a special network fully separate from the network
that carries the actual call.
2) In US
telecommunications traffic engineering, it means Hundred (C) Call Seconds,
and is a
unit of traffic quantity equivalent to
a phone call 100 seconds long.
CCS7 - Common Channel Signaling #7
signaling method in which a single channel conveys, by means of labeled
message, signaling information relating to a
multiplicity of circuits or calls and other information, such as that used
for network management.
1) Packet switching information
grouped in units of uniform size. Cells are fixed-length packets. (e.g. ATM 53-byte cells)
2) A small group acting as a unit in a larger organization (e.g. one of the
separate geographical areas covered by a radio
transceiver antenna in a multi-antenna cellular phone system, a spreadsheet cell, a biological cell, etc.).
Packet switching technique which
uses packets of fixed length, resulting in lower processing speeds. Also known as BISDN and ATM.
Cellular Service Type
Type 1 - ANI only
identifies the mobile cellular system, Type 2 - ANI identifies the mobile DN
placing the call, but does not necessarily
identify the true call point of origin, Roaming - Subscriber is "roaming" in another cellular network.
Roaming ANI identifies the mobile DN placing the call, but does not necessarily identify the true forwarded-call
Central Office - CO
One local Class 5
Switch with lines to customer locations. (Usually less than 100,000
telephone lines per Central Office.) COs are
usually owned and operated by LECs or BOCs. COs have
connections to Tandem (Class 4 Toll Offices) and often connect
directly to other COs and IECs like AT&T, MCI,
WorldCom, Sprint, etc. A CO is a major equipment center designed
to serve the communications traffic of a specific
geographic area. CO coordinates are used in mileage
calculations for local and interexchange service rates. A Non-Conforming CO
is one that does not (yet) support Equal Access.
Central Office Terminal - COT
used for multiplex/demultiplex and analog/digital conversion functions at
office end of the loop T-carrier
circuit. May be provisioned to provide line-powering or to interface with a DS-1 signal at the DSX.
A service that is functionally
similar to a customer-premise PBX, but provided by means of
equipment located in a Central Office, and uses
that equipment to route internal calls from one
extension to another, to route incoming phone calls directly to the
appropriate extension, to
handle direct dialing of
outbound calls, and to provide other PBX-like features.
CEPT - Conference on European Post and Telegraph
A European organization which develops
standards and defines interfaces for telecommunications.
CER - Cell Error Ratio
The ratio of erred
cells in a transmission in relation to the total cells sent in a
The measurement is taken over a time
interval and on an in service circuit.
CFA - Customer Facility Assignment
CGA - Carrier Group Alarm
alarm condition for a T1 or E1 multiplexer or DACS frame which results in
being taken out of service. Normally a
RED, YELLOW, or AIS condition.
A telecommunications path (pipe) of
a specific capacity (speed) between two locations in a
network. The smallest subdivision of a circuit
that provides a type of communication service;
usually a path with only one direction.
A multiplexer that merges 24
voice and/or data circuits into a single T1 (DS-1) digital
Channel Extension / Channel Networking (Service)
Interfaces that allow high-speed computers to
communicate with remote devices at local
speeds (over T1/T3 lines).
Channel Service Unit / Data Service Unit - CSU / DSU
Manages digital transmission, monitors signals for
problems. Responds to Central Office commands. It
performs many of the functions that modems do, but it does not have to
convert digital signals to/from analog, since the end
device and the underlying transmission facility are both digital.
(multiplexer, channelizer, etc.) required to provide a connection point for
one channel. For dedicated circuits, there is a
recurring charge rate element for each channel termination.
To subdivide (or break
out) a broadband transmission system into multiple communication channels.
CIR - Committed Information Rate
In a frame
relay network, each PVC is assigned a Committed Information Rate, measured
in bits per second. The CIR represents the
average capacity that the Port Connection should allocate to the PVC. This rate should be consistent with the
expected average traffic volume between the two sites that the PVC connects. The CIR that is assigned to a PVC
cannot exceed the speed of either the originating or terminating Port Connection.
A switched or dedicated
communications path with a specified bandwidth (transmission
Circuit Media Wire Cables
Two Wire (not
twisted), Twisted Pairs (Radio Frequency Interference Canceling), Shielded
Coaxial Cable, Terrestrial Microwave, Satellite
Microwave, Fiber Optic.
A switching method where
a dedicated path is set up between the transmitter and receiver. The
connection is transparent, meaning that the
switches do not try to interpret the data.
Two cities between which an IEC
offers long-distance service. When ordering a new dedicated
circuit or trunk group, "city pair"
NPA/NXXs are used to determine the switch location.
CLASS - Custom Local Area Signaling Service
A grouping of optional enhancements to basic local exchange telephone
service which employs
digital switching and
out-of-band network-control signaling to give subscribers the ability to
and selectively reject, forward, trace and
redial incoming calls.
Class 3 - IEC - Interexchange Carrier
Hierarchical interconnection for Class 4 and optional Class 5 Switches
Class 4 - Tandem Office - Toll Office
Interconnection for Class 5 Switches and long distance via Class 3 IECs.
Optional direct connection to higher volume Class
4 sites. A Class 4 may also serve as a Class 5 CO.
Class 5 - Central Office -End Office
Connection to local Customer Premise Equipment and local switching. Capacity
typically is up to
100,000 lines, 1 to 10 NXX.
Class of Service - COS
A special limitation
on what numbers can and cannot be called. International, 809, 809 + Canada, 48 contiguous states, etc.
Client/Server - C/S
A distributed computing
model in which clients request data and processing from servers. Servers usually have higher capacity than clients (but
not necessarily). Client/Server exploits less expensive hardware than host-based computing, but C/S
application design and resource management must be
more sophisticated. See Peer-To-Peer
CLEC - Competitive Local Exchange Carrier
CLLI (pronounced "silly") - Common Location Language
A unique identifier assigned to LEC
End Offices and Tandem (Class 4 switch) Toll Offices groups. The CLLI code is the designation for a central
office, or the area served by a central office and is a BellCore standard. Example: PTLDOR69CG0 The first four
digits designate the location (city); digits 5 & 6 are the state code, digits 7 & 8 are the CO
name, digits 9 through 11 specify equipment type. A "T" in the eleventh field would
identify the location as a Tandem office.
The end of a line (such as a
WATS 800 or foreign exchange line) from which all calls are directed to or from a single point. Private lines normally
have two closed ends.
CLR - Circuit Layout Record
means of displaying the path a circuit takes to get from one location to
another. Usually produced via a computer
software program, or hand drawn, and includes locations, equipment,
and facilities within the circuit path.
SCP 800 Number Translation
Database (To POTS)
Customer Owned and Maintained
Close Of Business (completed by
end of business day)
COCOT - Customer Owned Coin Operated Telephone
Private pay phones leased or owned by an individual,
private company or institution (not the local
CODEC - enCOde/DECode
A device that
converts (encodes) analog signals into a form for transmission on a digital
The digital signal is then decoded
back to analog at the receiving end of the transmission link.
Codecs allow voice and video transmission over
digital links. Codecs may also support signal
compression. (Contrast modem)
A coin-operated pay phone
with restricted access to some services (e.g. International calling).
Coin phones have subclasses of Public, Semi Public,
A call that is paid for by the
receiving/destination phone number. Requires approval/authorization
of the person being called.
The physical placement of
in-service customer telecommunications equipment at a carrier's central office, point of presence or other network
COM - Continuation of Message
used by the ATM Adaptation Layer to indicate that a particular ATM cell is a
continuation of a higher layer information packet
which has been segmented.
A carrier that holds itself
out as serving the public (or a segment thereof) indifferently (i.e.,
without regard to the identity of the customer
and without undue discrimination). Common carriers may vary rates based on special considerations and may
in fact serve only a small fraction of the
A system of
hardware and software connecting two end users.
Compression or expansion of
encoding levels to increase signal quality when digitizing an analog
Competitive Telecommunications Association - CompTel
An industry association of IECs that does not include
AT&T, MCI or Sprint, but does include most
medium-sized communications carriers. CompTel may also refer to one of the
Competitive Access Provider - CAP
other than a LEC, RBOC, or AT&T that is authorized to provide access
customers within the same market
A method of
encoding/decoding signals that allows transmission (or storage) of more
than the media would otherwise be
able to support. Both compression and decompression require
processing capacity, but with many products,
the time is not noticeable.
Computer Aided Design/Computer Aided Manufacturing -CAD/CAM
CAD - A computer application using software and
high-resolution graphics for drafting, design and
similar engineering functions.
Computer-controlled manufacturing. When CAD is connected with CAM it is
Computer Integrated Manufacturing. CIM allows efficient production of small
When CAD and CAM are distributed over a geographical
area, significant communication network capacity may
1. The relative arrangement,
options, or connection pattern of a system and its sub component
2. The process
of defining an appropriate set of collaborating hardware and software
objects to solve a particular problem.
1. A Point-To-Point Dedicated or
Switched communication path.
2. An ATM connection
consists of concatenation of ATM layer links in order to provide an
end-to-end information transfer capability to
A legally-binding agreement
between a vendor and a customer to provide Products, Services or
Features in a specified quantity and quality,
for a specified price, during a specified period of time.
The provision of
regulated service pursuant to individually negotiated contracts, instead of
Services and rates based
on contracts negotiated with individual customers, but theoretically
available to all customers. AT&T has filed
several hundred contract tariffs.
A repeater that also converts
from one media type to another, such as from fiber to copper, and often called a media adapter.
Coordinates Vertical and Horizontal (V&H)
Grid points used to determine straight-line
mileage between locations such as PoP, CO, etc.
Two or three digit codes used
for International calls outside of the North American Numbering Plan area codes. Dial: 011 + country code + city
code + local phone number) (e.g. "011 + 91 + 22 +123- 4567" 91 = India, 22 = Bombay)
CPCS - Common Part Convergence Sublayer
The portion of the convergence sublayer of an AAL that remains the
same regardless of the traffic type.
CPN - Calling Party Number
New acronym for
ANI that identifies the originating telephone number field in an SS7
Conduit, Raceway, Equipment Ducts,
and FACilitieS. Generic collective term for infrastructure used in cabling.
Cross-Aisle Tie Circuit
between physically separated distribution frames.
A point in a network where a
circuit is connected from one facility to another by cabling between
equipment such as DSX bays or distribution
frames; or, is accomplished via a software command
within a piece of equipment such as a DACS to
connect one circuit to another.
CS - Convergence Sublayer
procedures and functions that convert between ATM and non-ATM formats.
This describes the functions of the upper half of the
CSB - Client Support Bulletin
information to RespOrgs about NPA splits, etc.
CSPDN - Circuit Switched Public Data Network
Circuit oriented public network usually based
CSU -- Channel Service Unit.
A device used to connect a digital phone line coming in from the phone company to network access equipment located on the customer premises. A CSU may also be built into the network interface of the network access equipment.
An individual person or
organization that purchases (orders, requests, or may be billed for)
service. A customer may be related to an entity
that pays for products. For example, a subsidiary company may have its own customer identification even
though the parent company pays all charges. A billable customer may be someone that merely accepts an
operator service call or a casual customer that
dials a CIC code (like 10555) without presubscribing. A service provider or
an agent may act as (or on behalf of) a customer.
(Contrast with End User)
The local facility
where the circuit terminates.
Customer Premise Equipment - CPE
Communications equipment (such as PBX switches, origination/termination
adapters, multiplexers, modems, codecs,
telephones, computers, etc. - but not including carrier lines) at the
customer's location that connects to carriers'
Products and Services. CPE may be COAM or provided by the carrier. Primary CPE suppliers include: AT&T,
Northern Telcom, NEC, Phillips, Siemens, Erickson, etc.
Customer Record Information System - CRIS (pronounced
A system used by many
LECs to maintain customer records.
Classification of customer
that defines procedural rules and the availability of products, services,
features and options (e.g. residential,
commercial, reseller, carrier, etc.)
The exact date/time that a phone
number, circuit, etc. is scheduled to be (or was) moved from one implementation (carrier, etc.) to another.
(e.g. moving an 800 number from MCI to WorldCom).
"10"+CIC+" #" followed by an AuthCode for IntraLATA
Cycle - A recurring series of events
(e.g. Business Cycle, System Life Cycle, etc.)