Glossary of Terms
A-B C-D E-F G-H I-J K-L M-N O-P Q-R S-T U-V W-X Y-Z
Admission
Admission of ordinary shares to trading on AIM, becoming effective in accordance with Rule 6 of the AIM Rules.
AOR
Address of Record. Generally refers to the telephone line. Users might relate an extension to an AOR.
ARPU
Average Revenue Per User.
BLA
Bridged (or Bridge) Line Appearance. A copy of another user’s Call Appearances enabled by PBX and IP call control platforms. Also referred to as SCA or Shared Call Appearance.
BLF
Busy Lamp Field. A device that shows which phones in a system are in use, ringing, or on hold.
CAGR
Compound Annual Growth Rate.
CAPEX
CAPital EXpenditure.
CatX
Category of Performance. Determines LAN cabling carrier capacity. The higher the number, the higher the capacity.
Cat3
Cabling of either 22 or 24 gauge. Can support applications up to 16 MHz carrier frequency. Applications include POTS, ISDN, T-1, and 10Base-T Ethernet. Has insufficient bandwidth to carry VoIP traffic.
Cat5
LAN cabling which is available in varying gauges. Can support applications up to 100 MHz carrier frequency. Applications include 10/100Base-T Ethernet, and 155 Mbps ATM LANS. Cat5e (enhanced) is commonly installed for LAN connectivity, and has enough bandwidth to carry both voice and data traffic.
Centrex
A centralized telephone service provided by a telephone company, where a portion of the telephone exchange switch capacity is used to provide the equivalent of a PBX service for the customer.
CPE
Customer Premises Equipment. Terminal equipment connected to the telephone network and residing on the customer’s premises. Termed CTE – Connected Telecommunications Equipment – in Europe.
CSU/DSU
Channel Service Unit/Data Service Unit. A customer-premise device that terminates a digital channel.
DHCP
Dynamic Host Configuration Protocol. A TCP/IP protocol that enables PCs to get temporary or permanent IP addresses from centrally administered servers.
Dial Plan
Rules that establish the expected number and pattern of digits for a telephone number.
DND
Do Not Disturb. A handset feature enabled by a PBX or IP call control platform that prevents incoming calls from ringing through to the user’s phone.
DSL
Digital Subscriber Line. High speed Internet connection over regular telephone lines.
DTMF
Dual Tone Multi Frequency. The technology that generates a combination of two tones, one high frequency and one low, when dialing a touchtone or push button phone.
Everybody Wins
Search citel.com for everybody wins (all lower case) and see what happens.
FTP
File Transfer Protocol. A TCP/IP protocol that is commonly used to access Internet-linked file archives around the world.
FXO
Foreign Exchange Office. In VoIP, FXO signifies a port or line on the handset or call control platform that connects to the PSTN.
G.711
Algorithm designed to transmit voice at digital bit rate 64 Kbps (no compression).
G.726
Algorithm designed to transmit voice at digital bit rates 32 and 24 kbps. Also transmits less commonly at 40 or 16 kbps.
G.729
Widely supported new voice algorithm. Transmits, codes, and decodes voice at 8 Kbps (high compression).
GUI
Graphical User Interface. A generic name for any computer interface that substitutes graphics for characters.
HTML
HyperText Markup Language. The software language used to create World Wide Web pages.
IAD
Integrated Access Device.
IP
Internet Protocol. A standard-describing software that keeps track of the Internet’s addresses for different nodes, routes outgoing messages, and recognizes incoming messages. See TCP/IP.
IP PBX
Internet Protocol Private Branch eXchange. A customer-premise call control server that routes voice traffic. Connects via Ethernet LAN and sends voice in IP packets.
ISP
Internet Service Provider. A vendor who provides access for customers to the Internet and the World Wide Web. Almost all Hosted VoIP Service Providers are also Internet Service Providers. Hosted VoIP SPs may also be referred to as a TSP (Telephone Service Provider) or ITSP (Internet Telephone Service Provider).
LAN
Local Area Network. A communications network, most commonly Ethernet, connecting devices inside a building or campus.
LCD
Liquid Crystal Display. Common technology used in flat-panel computer monitors, televisions, and some phones.
LED
Light emitting diode. Commonly used for calculators and computer devices.
MAC
Moves, Adds, and Changes. Also short for Media Access Control address, a unique identifier attached to most network adapters. Of course, Mac is also short for Macintosh, the best computers in the world, made by Apple, Inc.
OPEX
OPerating EXpenditure.
PBX
Private Branch eXchange. A circuit switched telephony server. PBXs are premise-based hardware that serve a single enterprise or office. PBXs often use proprietary digital-line protocols, although some are analog-based.
Placing
The raising of funds through institutional investors and other investors.
PoE
Power Over Ethernet. A standard (802.3af) that powers IP phones via the LAN cabling instead of a wall outlet.
POTS
Plain Old Telephone Service. The basic service supplying standard single line telephones, telephone lines, and access to the PSTN.
Protocol
Rules controlling data flow in a communication system.
PSTN
Public Switched Telephone Network. This is the telephone network based on copper wire that carries analog and digital voice traffic. The phone company’s traditional system of completing a call.
PSU
Power Supply Unit. Any integrated or external module or connector that supplies power to a device.
QoS
Quality of Service. There are two QoS definitions that apply to enterprise telephony. First, QoS is a control mechanism that prioritizes data and voice traffic. QoS capabilities are built into some routers and switches or can be delivered via unique devices. Next, QoS is a set of standards for subscriber voice quality, including clarity, volume, echo, delay, etc. Enterprises with digital networks monitor their established standards by setting and reviewing error conditions.
RJ
Registered Jacks. Telephone and data plugs registered with the FCC.
RJ-11
A six conductor modular jack, typically wired for four conductors. It is the jack on home phone lines, and is the most common telephone jack in the world.
RJ-21x
25-pair Amphenol-type connector, commonly connecting Key systems and PBXs.
RJ-45
The common term for 8P8C modular plugs and jacks with eight conductors, crimped to Cat5e or Cat6 cable and used in Ethernet.
ROI
Return On Investment.
Router
An interface between two networks. Routers buffer and forward data packets across a network.
RS-232
A set of standards for communicating between computers, terminals, and modems.
SCA
Shared Call Appearance. See BLA.
SIP
Session Initial Protocol. An standards-based telecommunications protocol that sets up phone calls, multimedia conferencing, instant messaging, and other types of real-time communications on the Internet. SIP can be used with TCP, UDP and other transports.
SIP trunking
A technology that enables point-to-point Voice over IP connections.
SLA
Service Level Agreement. An agreement between a user and a service provider, defining the nature of the service provided and establishing a set of metrics to measure the level of service provided.
SME
Small to Medium-sized Enterprise. Also referred to as SMB (Small to Medium-sized Business).
SNMP
Simple Network Management Protocol. The most common method of managing networks.
SOHO
Small Office/Home Office.
Switch
For telecommunications purposes, a switch is a device that looks at the destination address of voice data and opens or closes circuits and selects paths.
TAM
Total Addressable Market.
TCO
Total Cost of Ownership.
TCP/IP
Transmission Control Protocol/Internet Protocol. Together, these two are the protocol used to make connections on the Internet, as well as across many other networks.
TDM
Time Division Multiplex. A technique for transmitting a number of separate data and voice signals simultaneously over one communications medium.
Telnet
A program that allows connections to other computers on the Internet. Used for remote configuration and management.
TVA
Telephone VoIP Adapter. Enables digital and analog handsets to operate on an IP telephony platform.
UPS
Uninterruptible Power Supply. A device that supplies clean, consistent power to a phone system or computer when the power company source shuts down or is inconsistent.
URL
Universal Resource Locator. Another term for Internet address.
UTP
Unshielded Twisted Pair. The most common type of copper telephone wiring. An inexpensive alternative to coaxial cable and fiber-optic cable in small deployments. STP or Shielded Twisted Pair is the same type of wiring, enclosed in a shield that functions as a ground.
VAR
Value Added Reseller. Typically an organization that packages standard products with software solutions for a specific industry.
VoIP
Voice over Internet Protocol. The aggregate protocols and technology of encoding a voice call that allows the call to be transmitted along with data over a network. Such data network may be the Internet or a corporate Intranet.
VPN
Virtual Private Network. A network that uses the Internet but has security features limiting access to authorized users.
WAN
Wide Area Network. A public network that extends beyond the office or campus.
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