What is broadband

Broadband is the term frequently used to describe faster Internet capability when compared with traditional modem dial-up Internet access.

Networking.com provide a more technical definition:

"In general, broadband refers to telecommunication in which a wide band of frequencies is available to transmit information. Because a wide band of frequencies is available, information can be multiplexed and sent on many different frequencies or channels within the band concurrently, allowing more information to be transmitted in a given amount of time (much as more lanes on a highway allow more cars to travel on it at the same time). Related terms are wideband (a synonym), baseband (a one-channel band), and narrowband (sometimes meaning just wide enough to carry voice, or simply "not broadband," and sometimes meaning specifically between 50 cps and 64 Kpbs).

Various definers of broadband have assigned a minimum data rate to the term. Here are a few:

Newton's Telecom Dictionary: "...greater than a voice grade line of 3 KHz...some say [it should be at least] 20 KHz."
Jupiter Communications: at least 256 Kbps.
IBM Dictionary of Computing: A broadband channel is "6 MHz wide."
It is generally agreed that Digital Subscriber Line (DSL) and cable TV are broadband services in the downstream direction."

Broadband, or more simply, faster Internet connections can be delivered through a range of technologies. These include:

• xDSL
• Cable
• Radio/Microwave
• Satellite
• Wireless (optical)

Broadband tends to be more expensive than dial-up or narrowband, but check with the ISP. Most broadband access is unmetered. This means you pay a monthly unmetered or ‘flat’ rate to access the Internet at any time without any call charges. With no call fees to pay, you know what your monthly bill is going to be. However, there may be installation costs that are worth checking out before signing up. Worth considering for frequent users who want faster access to the Internet. Unmetered refers to the phone connection for the access, the amount of data downloaded or uploaded may be restricted by a bandwidth limit.

				Comparing broadband solutions

DSL vs. Cable

Cable modems are an alternative for broadband residential service but are generally not suitable for business-class broadband for the following reasons:

• Service: Most business locations are not serviced by cable and therefore can not be connected. In addition, cable service has been historically unreliable. Each time the "cable goes out" so does your Internet connectivity.
• Speed: The cable users are set up as a LAN or Local Area Network to share a single fiber connection among the hundreds (maybe even thousands) of subscribers. As more and more of your neighbors connect, your bandwidth or line speed diminishes proportionately. Cable companies typically can not guarantee a minimum available bandwidth. Once the initial speed has been determined and set at installation, your bandwidth never changes.
• Security: Being on a Local Area Network does not provide for a secure connection for electronic commerce. Your connected neighbors and competitors will be able to intercept your credit card or other sensitive, confidential company data using a device called a sniffer. DSL is a direct connection between your business and our equipment located in secure telephone central offices. The DSL line is never shared.

DSL vs. ISDN

DSL is actually a higher speed version of ISDN. ISDN although digital, still requires the connections to be "dialed". In addition, many telephone companies charge a base rate plus per-minute usage charges that can add to hundreds of dollars every month. ISDN uses up to two 64Kbps circuits (B-channels)for a maximum speed of 128Kbps. IDSL is very much like ISDN however it is always-on, does not have per-minute charges and combines the third ISDN circuit or "D-channel) for a fixed speed of 144Kbps in both directions. As IDSL utilizes the same circuit cards as ISDN, IDSL can be provided to customers that are on Digital Subscriber Loops (also called Digital Carrier or SLIC's).

DSL vs. T1

T1 data lines are the most common high speed data lines in use today. They are used to carry both data and digital multiplexed voice channels (24 toll grade voice channels per T1). DSL is capable of providing T1 speeds within a limited distance to the telephone company central office (C.O.) at a fraction of the T1 price. The cost of a T1 is very high due to special requirements that are placed on the cabling between the C.O. and the user. These requirements include the removal of all bridging and taps and the installation of repeaters along the cable. At longer distances, DSL can provide Fractional T1 speeds. DSL is clearly a lower cost alternative to a T1 circuit.

				Broadband Glossary

10BASE-T

The Institute of Electrical and Electronic Engineers (IEEE) specification for Ethernet over unshielded twisted pair cable at 10Mbps.

100BASE-T

The Institute of Electrical and Electronic Engineers (IEEE) specification for Ethernet over unshielded twisted pair cable at 100Mbps.

ADSL Asymmetric Digital Subscriber Line.

High speed technology utilizing existing phone lines to transmit data. Typical speeds are from 144Kbps to over 8Mbps currently.

ATM Asynchronous Transfer Mode.

High Bandwidth packet technology that uses 53 byte fixed sized cells to deliver data, voice and video.

ATU ADSL Transceiver Unit.

Equipment used for DSL technology. In the Central Office it is called ATU-C (central) and in the Customer locations it is called ATU-R (remote).

Backbone

A central very high speed fiber network that is used to connect smaller, independent networks.

Bandwidth

A term used to describe the number of bits that can move across a communications system in a given amount of time.

BPS Bits per second.

The number of bits passing a point every second. The rate of transmission for digital signals. Broadband Data transmissions of voice, data and video signals over a single medium at high speeds.

Exchange.

The building used by telephone companies to connect local users to their infrastructure.

CPE Customer Premises Equipment.

Terminating equipment supplied by carrier for use at customer site i.e. Modems, phones, routers.

DS3

Digital transmission at 45Mbps, usually operates on fiber optics. Equivalent to 30 T1 circuits.

DSL Digital Subscriber Line.

Technology that combines two way voice and data transmissions at very high speeds over normal phone lines.

DSLAM Digital Subscriber Line Access Multiplexer.

Equipment used in the telephone company Central Office to concentrate local DSL users onto a high capacity Backbone.

DSU Digital Service Unit.

Digital device at customer premises to facilitate xDSL service. Also known as a Modem or Router.

Ethernet

Term used to describe a baseband LAN specification originally designed by Xerox. IEEE 802.3 describes the current standards for this protocol.

Firewall

A secure gateway or virtual wall between two different computer networks that will prevent unauthorized use or access.

Fractional T1

A portion of a T1 circuit that has been divided into 24 separate 64Kbps channels. Actual size is a multiple of 64.

Frame Relay

A data communication technology based on packet switching of variable length frames that are protocol independent.

HDSL

High bit rate Digital Subscriber Line.

IDSL Integrated Digital Subscriber Line.

An ISDN based version of DSL operating at 144 Kbps.

ISDN Integrated Services Digital Network.

Public circuit switched network that combines voice and data into a single medium. Usually runs at 64K or 128K, predecessor to DSL technology.

ISP Internet Service Provider.

Company that provides connection to the Internet typically via a dial-up link

Kbps Kilo Bits Per Second.

A measure of time relating to telecommunications speeds. One kilobit is 1,024 bits of information, the higher the number the faster the transmission speed.

LAN Local Area Network.

A data communications networks of computers, printers, file servers, etc. in a local environment.

Local Loop Also called the "last mile".

The length of telephone wire from the local Exchange (or Central Office) to it's final termination at customer premises. Usually about 1-3 miles or less.

Mbps Mega Bits Per Second.

Like Kbps a measure of transmission rates. One Megabit equals 1,048,576 bits of information. 1.5Mbps is over 50 times faster than a 28.8 Kbps dial-up Modem.

NIC Network Interface Card.

The hardware that handles the protocol conversion between your computer and a connected network. Used in DSL service to talk to router.

POTS Plain Old Telephone Service.

As it sounds, your basic telephone service.

Repeater

Electronic device used to regenerate and enhance signal quality over long cable distances.

Router

Electronic device that transmits and receives data packets in a network.

SDSL

Symmetrical Digital Subscriber Line.

T1

Digital transmission at 1.544Mbps.

T3

Digital transmission at 45Mbps. Basically 30 T1 circuits.

TCP/IP Transmission Control Protocol/Internet Protocol.

Open communication protocol that allows computers with different operating systems to communicate with each other on the Internet.

VPN Virtual Private Network.

A network service that is provided over a public network that is secure and works like a private network.

WAN Wide Area Network.

A network with devices over a wide geographical area.

xDSL

Refers to all variations of the DSL family or technologies.