The following glossary of telecommunications terms may be helpful when researching telephone equipment service providers. Analog — a transmission method that employs continuous electrical signals that vary in amplitude or frequency. Traditional telephone service uses analog technology. Automated Attendant — a system that greets callers with a recorded message, and instructs them to enter various numbers from their phones to get information or to route calls to specific extensions. Bandwidth — frequency range that can be accommodated by a transmission line. The bandwidth determines the rate at which data can be transmitted. A bigger bandwidth will increase the amount of traffic your connection can accommodate. Broadband Technology — uses data wires that have greater capacity for transmission and therefore can handle more traffic. Bundling — grouping various telecommunications services as a package to reduce expenses associated with delivering services. CAT 3, CAT 5 — standards for wiring within an office or residence. CAT 3 (Category 3) is adequate for most telephone applications. CAT 5e is the accepted minimum for data wiring.  CAT6 is a gigabit capable cabling system for future applications. CLEC (Competitive Local Exchange Carrier) — company competing with the established local telephone company by providing its own network or switching or both. Dedicated Service — provides data and voice communications over a circuit that is used for a single purpose. DID — direct inward dial phone number. This allows an outside caller to dial directly to an individual user’s telephone handset. Digital — method of representing information using "1" and "0" numbers. DSL (Digital Subscriber Line) — a broadband access technology that allows transmission at bandwidths several times higher than permitted by conventional analog modems. DSS — direct station select A button on a phone system endpoint used to directly dial a person or extension associated with that button. Hunting — calls to a particular number may be arranged so that when a line is busy, the call will search a group of lines in a specified sequence until an available line is found. Hunt Group — the group of lines, or stations used for a hunting sequence. IP Telephony — method used to send voice traffic across a data network, also known as VoIP or Voice over IP. Voice signals are broken down into packets and reassembled at the receiving end. This eliminates the need for separate voice and data networks by converging all traffic on one network. ISDN (Integrated Services Digital Network) — high speed digital service that offers simultaneous voice and data transmission over the same channel. LAN (Local Area Network) — Data sharing network created within the confines of a local area, such as a building or a group of buildings that consists of data equipment, cable and computers. Least-Cost Routing — automatically chooses the least expensive long-distance carrier for a call. This feature is usually not available on key or hybrid systems. PSTN — Public Switched Telephone Network The regular, copper wire telephone system used for voice calls. SMDR — SMDR is a telephone call tracking and reporting system that automatically divides phone bills by department, and lists the name of each caller. Soft PBX — the term used to describe a software application that provides server based telephony. Performing similar functions to a hardware PBX, Soft PBXs offer a range of PBX functions, voicemail and integration with other server based applications such as Unified Messaging and contact management systems. Switch — a system used to control routing of transmission signals entering and leaving a central office. T-1 — private line digital transmission service providing fast transmission capability for voice and data. TAPI — Telephone Application Program Interface Developed by Microsoft, 1st and 3rd party TAPI are the standard interfaces for CTI applications. Unified Messaging — Unified Messaging (UM) systems provide one centralized mailbox for email, voice and fax messages. All message types can be viewed, replied to, saved or deleted in the same Inbox using a familiar message management system such as Microsoft Outlook or Lotus Notes. VoIP (Voice over IP) — the transmission of voice traffic over a wide area network or the Internet using the IP signaling standard (Also known as IP Telephony). WAN (Wide Area Network) — Any Internet or network that covers an area larger than a single building or site. Wireless Wide Area Network — Companies with more than one building on a campus or in close proximity in a city can use “Wi-Fi” technology – or higher frequency, high-speed radio technologies – to build wireless “bridges” between sites.  This bridge can allow for wireless phone communication between the buildings.