Telco Terms: Telecommunications Terms explained
Asymmetric digital subscriber line (ADSL) is a new modem technology that converts existing twisted-pair telephone lines into access paths for high-speed communications. ADSL can transmit more than 6 Mbps (Megabytes per second) to a subscriber — enough to provide Internet access, video-on-demand, and LAN access. In interactive mode it can transmit more than 640 kbps in both directions. This increases the existing access capacity by more than 50-fold enabling the transformation of the existing public network. No longer is it limited to voice, text, and low-resolution graphics. It promises to be a system that can provide multimedia (including full-motion video) to the entire country.
Bandwidth: The transmission capacity of an electronic line such as a communications network, computer bus or computer channel. It is expressed in bits per second, bytes per second or in Hertz (cycles per second). When expressed in Hertz, the frequency may be a greater number than the actual bits per second, because the bandwidth is the difference between the lowest and highest frequencies transmitted.
Broadband: High-speed transmission. The term is commonly used to refer to communications lines or services at T1 rates – 1.544 Mbps (Megabytes per second) – and above. However, the actual threshold of broadband is very subjective and may be below or well above T1, depending upon the situation. In every case, it involves transmitting at higher speeds than what has been common for some time.
CLEC: Competitive Local Exchange Carrier - a company that competes with the already established local telephone company by providing its own network and switching. The term distinguishes new or potential competitors from Incumbent Local Exchange Carriers (ILECs) and arises from the Telecommunications Act of 1996, which was intended to promote competition among both long-distance and local phone service providers.
Collocation: A market in which an ISP may provide rack space within its facility for customers to collocate their own servers for a multitude of applications that save their companies a moderate amount of money by not having to host everything at their respective offices.
DSL: Digital Subscriber Line – a technology that dramatically increases the digital capacity of ordinary telephone lines (the local loops) into the home or office. DSL speeds tied to the distance between the customer and the telco central office. The technology is geared to Internet access with its asymmetric versions (faster downstream than upstream) and short haul connections with symmetric versions (same rate coming and going).
ILEC: Incumbent Local Exchange Carriers, such as BellSouth, Sprint and Verizon.
ISDN: Integrated Services Digital Network – an international telecommunications standard for transmitting voice, video and data over digital lines running at 64 Kbps (kilobytes per second). The telephone companies commonly use a 64 Kbps channel for digitized, two-way voice conversations. ISDN service is available in most parts of the US.
UNE: Unbundled Network Elements - Physical or functional elements of a network that, under the Telecommunications Act of 1996, must be made available for CLECs and ICPs by the ILECs.