Glossary
Glossary
ADSL Asymmetric Digital Subscriber Line; High speed Internet access that works over a regular phone line. Downstream speeds average 1.54 mbps, and upstream speeds range from 256 kbps 512 kbps. ADSL is typically used in residential areas.
Bandwidth The amount of data transmitted in a given amount of time; usually measured in bits per second, kilobits per second, and megabits per second.
Bit A single unit of data, either a one or a zero. In the world of broadband, bits are used to refer to the amount of transmitted data. A kilobit (kb) is approximately 1000 bits. A megabit (Mb) is approximately 1,000,000 bits.
Bottleneck Occurs when data passes through a port at a slower speed than the actual data transmission.
Broadband / high speed Generally referred to as an internet connection faster then 128 kbps. Dial-up at best is 56 kbps, so just over twice as fast as Dial-up and you are entering broadband territory.
Byte 8 bits. A kilobyte (KB) is approximately 1000 bytes. A megabyte (MB) is approximately 1,000,000 bytes. Bytes are usually used to refer to the size of files stored on a computer's hard drive.
Cable modem A modem that connects to your cable TV line in order to give you high speed access to the Internet.
CO (Central Office) A circuit switch where the phone lines in a geographical area come together, usually housed in a small building.
Coaxial Cable A type of cable that can carry large amounts of bandwidth over long distances. Cable TV and cable modem service both utilize this cable.
DHCP Short for Dynamic Host Configuration Protocol, a protocol for assigning dynamic IP addresses to devices on a network. With dynamic addressing, a device can have a different IP address every time it connects to the network. In some systems, the device's IP address can even change while it is still connected.
Dialup A term used to refer to Internet access using a phone modem. Usually, the user dials a telephone number using the computer in order to connect to the Internet. The maximum bandwidth of a dialup connection is 56 kbps.
DSL Short for Digital Subscriber Line, DSL technologies use sophisticated modulation schemes to send data over the copper wire used for your phone connection and is considered high speed or broadband Internet access.
DSLAM (Digital Subscriber Line Access Multiplexer) A device located in the Central Office switch that enables it for xDSL capabilities.
Downstream or Download Speed Data flowing from the Internet to your computer (Surfing the net, getting E-mail, downloading a file).
Encrypted Data (computerized information) is scrambled in order to prevent unauthorized access.
Ethernet A protocol developed in the 1970's that supports LAN's (Local Area Networks). Ethernet is capable of 10 mbps data transmissions, and "fast ethernet" is capable of 100 mbps.
Gigabit (Gb) (1) when used to describe data storage, 1,024 megabits (2) When used to describe data transfer rates, it refers to 10 to the 9th power (1,000,000,000) bits
Gigabyte (GB) 2 to the 30th power (1,073,741,824) bytes. One gigabyte is equal to 1,024 megabytes. Gigabyte is often shortened to GB.
Headend router The device, located at a cable provider, that manages all of the cable modems in a geographical area. The headend router has a direct connection to an Internet backbone.
IDSL ISDN Digital Subscriber Line; Combination of ISDN and DSL. Provides a 144 kbps connection.
Internet Backbone A company that owns large amounts of bandwidth. The bandwidth is leased to ISP's or telephone companies, which allows them to supply consumers with access to the Internet.
IP Address A unique numerical address for every computer that is connected to the Internet. If a computer has a static IP address, its IP address is always the same. If a computer has a dynamic IP address, its IP address is assigned by the ISP whenever the computer logs on. A static IP address is required to run a web server.
IP Assignment IP assignment is how your computer gets an IP address from your Internet Service Provider, DHCP, Static IP, or PPPoE are generally used.
ISDN (Integrated Services Digital Network) A digital signal that travels over existing copper phone lines. ISDN works in channels. Each B (Bearer) channel is capable of 64 kbps. BRI lines (Basic Rate Interface) consist of 2 B channels for a maximum Internet connection speed of 128k. PRI lines (Primary Rate Interface) consist of 23 B channels, also known as a T1 line. BRI's are used in residential areas, and PRI's are used for business.
ISP (Internet Service Provider) A company providing Internet access to consumers and businesses.
Kilobit (Kb) 1,024 bits for technical purposes, transfer rates are measured in kilobits per second, abbreviated as Kbps, and count a kilo as 1,000 bits.
Kilobyte (KB) Kilobyte is 1,024 bytes, but it is often used loosely as a synonym for 1,000 bytes. Data transfer rates are measured in kilobytes per second, abbreviated as KBps, and count a kilo as 1,000 bytes.
LAN (Local Area Network) A group of computers sharing resources (files, printer, Internet access). Usually, LAN's are set up using Ethernet cards and cable.
Latency Latency is also referred to as ping time, it is the time it will take a single packet of data to travel to a remote server, and return. Latency improves in proportion to line speed, (and faster speeds provide more bandwidth). Although, with a sufficiently small packet, the ping time is more a function of the number of hops between you and the remote server, congestion on the way, and so on. On a modem, ping time to your first hop (usually your ISP modem rack), is no better than 100ms (1/10th of a second). With larger packets, say, 2K, this could be around 1000ms (1 second) or more. Players of any internet interactive games know that latency is a key factor in deciding which game to join and how well it will play.
Loop Qualification Check A test that the telephone company can perform to see how far a customer is (in wire feet) from the Central Office switch.
Megabit (Mb) (1) when used to describe data storage, 1,024 kilobits (2) When used to describe data transfer rates, it refers to one million bits. Transfer rates are often measured in megabits per second, abbreviated as Mbps.
Megabyte (MB) (1) When used to describe data storage, 1,048,576 (2 to the 20th power) bytes Megabyte is frequently abbreviated as MB. (2) When used to describe data transfer rates, as in MBps, it refers to one million bytes.
Monthly download limits This is a limit, generally in Gigabytes to how much information you can receive from the internet. Websites, email, everything you see on your screen is part of your download limit.
Network A group of two or more computer systems linked together. There are many types of computer networks, including:
Local-area networks (LANs) - The computers are geographically close together (that is, in the same building).
Wide-area networks (WANs) - The computers are farther apart and are connected by telephone lines or radio waves.
Campus-area networks (CANs) - The computers are within a limited geographic area, such as a campus or military base.
Metropolitan-area networks (MANs) - A data network designed for a town or city.
Home-area networks (HANs) - A network contained within a user's home that connects a person's digital devices.
Network Card An internal card on a computer which allows the computer to be connected to a network. Also known as 10Base-T card, Network Interface Card (NIC), or Ethernet card.
Personal Web space Some Internet Service Providers allow you to host a small website from their servers. Typically this is not allowed to be commercial websites, but a website none the less.
Point to Point (P2P) We use this term for any connection that is from one point to another, such as a T1, DS3, and OC3 etc. These are typically used for business connections and are generally more expensive then residential services.
PPPoE Short for Point-to-Point Protocol over Ethernet, PPPoE relies on two widely accepted standards: PPP and Ethernet. PPPoE is a protocol that allows users to log on and off from their high speed or broadband internet connection.
Proprietary Equipment that does not conform to a standard. Proprietary computer equipment will typically only communicate with equipment of the same brand/type. SDSL
SDSL Symmetric Digital Subscriber Line - High speed Internet access that works over a regular phone line. Downstream and upstream speeds are equal and can be anywhere from 160 kbps - 1.54 mbps. SDSL can be used in business or residential areas.
Satellite It is possible to get Internet access via low level orbiting satellites, like those that provide TV services. You get a Satellite connection for your internet service, but you also need a dial-up modem to use the service. To view websites or send email you need to send a request to that server to send you the information and to send information you typically need to use dial-up service with a satellite Internet service and is considered high speed or broadband Internet access. Latency is also very high.
Serial Port The 9 or 25 pin ports on PC's that are used for connecting external devices to the computer, such as modems; also known as COM ports.
Static IP An address on your network that never changes. Static IP Addresses are obtained from ISP's.
Tier 1 Connection A direct connection to the Internet Backbone. Most ISP’s go through a Tier 2 carrier which increases latency and slows your reaction time. db3 broadband is on a Tier 1 connection.
Upstream or Upload Speed Data flowing from your computer to the Internet (sending E-mail, uploading a file).
USB (Universal Serial Bus) A way of connecting devices to a computer. One USB controller (2 ports) can support up to 127 devices. USB can transmit data up to 12 megabits per second, and it is a true plug and play interface. Windows 98 Second Edition and Macintosh OS 8.5.3 both support USB.
VDSL Very High Bit Rate DSL; Customers must be within 4,500 feet of the CO. Provides data rates of 13 - 52 mbps downstream and 1.5 - 2 mbps upstream.
WISP (Wireless Internet Service Provider) A company that provides Internet access with a wireless connection to your home or building.
Wireless It is possible to get Internet access via wireless options, think of a cordless phone or a cell phone. It works the same way and is considered high speed or broadband Internet access.
xDSL (Digital Subscriber Line) A term used to generalize all of the different types of DSL.