Glossary: A
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- AAL
- See Asynchronous
Transfer Mode Adaption Layer
- Abbreviated Dialing
- A feature that permits the calling party to dial the
destination telephone number in fewer than normal digits.
Abbreviated Dialing numbers must be set up in advance of their use.
Speed Dialing is a typical example of Abbreviated Dialing.
- Access
- The method, time, circuit, or facility used to enter the network.
- Access Coordination
- The design, ordering, installation, preservice testing, turn-up
and maintenance on local access services.
- Access Line
- The circuit used to enter the communications network.
- Account Codes
- Also known as Project Codes or Bill-Back Codes. Account Codes
are additional digits dialed by the calling party that provide
information about the call. Typically used by hourly professionals
(accountants, lawyers, etc.) to track and bill clients, projects,
etc.
- ACD - Automatic Call
Distributor
- A system designed to evenly distribute heavy incoming call
traffic among multiple attendants.
- ACNA - Access Carrier Name
Abbreviation
- (e.g. LDDS WorldCom's ACNA is "WTL") There can be multiple CICs per ACNA.
- Address Mask
- A 32-bit long mask used to select an IP address for subnet
addressing. The mask selects the network portion of the IP address and
one or more bits of the local LAN address.
- Address Translation
- The process of converting external addresses into standardized
network addresses and vice versa. Facilities interconnection of multiple
networks which each have their own address plan.
- Agent
- A person or organization that acts on behalf of another. In the
telecommunications industry, Agents typically are independent
individuals or companies that market the services of a carrier as if
they were employees of that carrier.
- Aggregate Discount
- A discount applied to multiple services based on the total dollar
value of those services.
- Aggregator
- An independent entity that brings several subscribers together to
form a group that can obtain long-distance service at a reduced rate.
Subscribers are billed by the original IXC. The aggregator only
provides the initial set-up of the plan. He usually provides no service
after that. Different than a reseller.
- AIN - Advanced Intelligent
Network
- A dynamic database used in Signaling
System 7. It supports advanced features by dynamically
processing the call based upon trigger points throughout the call
handling process and feature components defined for the originating or
terminating number.
- AIOD - Automatic Identified
Outward Dialing
- An option on a PBX that specifies
the extension number, instead of the PBX
number on outward calls (for internal billing).
- AIS
- Alarm indication signal usually all ones--F11111111. Also known as a Blue Alarm
which signals that an upstream failure has occured.
- Alarm
- A real-time indication or a signal of an abnormal situation or
event. Usually includes a Priority or Severity Code.
- Alternate Access
- A form of local access where the provider is not the LEC, but is authorized or permitted to provide such service.
- Alternate Access Carriers
- Local exchange carriers in direct competition with the RBOCs.
Normally found only in the larger metropolitan areas. Examples are
Teleport and Metropolitan Fiber Systems.
- Alternate Mark Inversion
(AMI)
- A line code used for T-1 and E-1 lines that has a 12.5% ones
density minimum, and the one conditions of the signal alternate between
positive and negative polarity.
- Alternative
Operator Services
- Operator services provided by a company other than a LEC, RBOC or AT&T that is
authorized to provide such service.
- AMA Record
- Automatic Message Accounting - See CDR
- AMI - Alternate Mark Inversion
- A line code used for T-1 and E-1 lines that has a 12.5% ones
density minimum, and the one conditions of the signal alternate between
positive and negative polarity.
- Ancillary Charges
- Charges for supplementary services comprised of optional
features, which may consist of both non-recurring and monthly
charges.
- Ancillary Features
- Subordinate, supplementary, subcomponent characteristics and
capabilities. Marketing options of Products and Services.
- ANI - See Automatic Number Identification
- A telephone number.
- ANSI - American National Standards Institute
- A United States-based organization which develops standards and
defines interfaces for telecommunications.
- Answer Supervision
- The off-hook indication sent back to the originating end when
the called station answers.
- AOS
- See Area Of Service or
Alternative Operator
Service
- AP
- Access Provider
- Architecture
- The specifications of a system and how its subcomponents
interconnect, interact and cooperate. Architectures are often
described in multiple levels of abstraction from low-level physical
to higher-level logical application and end-user views.
- Area Code Routing
- Route calls based on the originating ANI NPA
(area code). See
NPA-NXX Routing.
- Area of Service -
AOS
- The geographical area supported by a communication service.
For 800 numbers, if AOS is "CC", it is using Complex Call routing.
- ARI
- Automatic Room Identification (Hotel/Motel room number)
- ARP - Address Resolution Protocol under TCP/IP
- Used to dynamically bind a high level IP address to a low-level
physical hardware address. ARP is limited to a single physical network
that supports hardware broadcasting.
- ASR - Access Service Request
- A document (or data transaction) sent to the
LEC to order the local access portion of a circuit.
- ASTA
- Areas of Service State (list)
- Asynchronous (i.e.
Not Synchronous)
- A form of concurrent input and output communication transmission
with no timing relationship between the two signals. Slower-speed
asynchronous transmission requires start and stop bits to avoid a
dependency on timing clocks (10 bits to send on 8-bit byte). (Contrast
with Synchronous)
- Asynchronous Transfer Mode - ATM
- An international ISDN high-speed,
high-volume, packet-switching transmission protocol standard. ATM uses
short, uniform, 53-byte cells to divide data into efficient, manageable
packets for ultrafast switching through a high-performance
communications network. The 53-byte cells contain 5-byte destination
address headers and 48 data bytes. ATM is the first packet-switched
technology designed from the ground up to support integrated voice,
video, and data communication applications. It is well-suited to
high-speed WAN transmission bursts. ATM
currently accommodates transmission speeds from 64 Kbps to 622 Mbps. ATM
may support gigabit speeds in the future.
- Asynchronous
Transfer Mode Adaptation Layer - AAL
- A series of protocols enabling
ATM to be made compatible with virtually all of the commonly
used standards for voice, data, image and video.
- ATM
- See Asynchronous Transfer
Mode
- (Most common usage of ATM within telecommunications)
- Attenuation
- A loss of signal strength in a lightwave, electrical or radio
signal usually related to the distance the signal must travel (e.g.
fiber optic transmission must be regenerated approx. every 30
miles). Fiber optic attenuation is caused by transparency of the
fiber, bending the fiber at too small of a radius, nicks in the
fiber, splices, poor fiber terminals, FOTs, etc. (See EDOA), Electrical attenuation is caused by the resistance
of the conductor, poor (corroded) connections, poor shielding,
induction, RFI, etc. Radio signal attenuation may be due to
atmospheric conditions, 1 spots, antenna design / positioning,
obstacles, etc.
- AuthCode - Authorization Code
- A number used for security purposes to gain access to an
Interexchange Carrier's network.
Authorization codes are inherently required for all Feature Group-A and Feature Group-B
Circuits without ANI reporting. Authorization
codes are also required for
Travel Service and Cut-Through capabilities on Feature
Group-D circuits.
- Automatic
Number Identification
- Originating Number
(1) The number associated with the
telephone station(s) from which switched calls are originated (or
terminated).
(2) A software feature associated with Feature Group D
(and optional on Feature Group B) circuits. ANI provides the
originating local telephone number of the calling party. This
information is transmitted as part of the digit stream in the
signalling protocol, and included in the Call Detail Record for
billing purposes.
(3) ANI may also be used to refer to any phone
number.
- Automatic
Ring Down (ARD)
- A private line connecting a station instrument in one location to a
station instrument in a distant location with automatic two-way
signaling. The automatic two-way signaling used on these circuits
causes the station instrument on one end of the circuit to ring when the
station instrument on the other end goes off-hook. This circuit is
sometimes called a "hot-line" because urgent communications are
typically associated with this service. ARD circuits are commonly used
in the financial industry. May also have one way signaling. Station
"A" rings Station "B" when Station "A" goes off hook, but Station "B"
cannot ring Station "A".