Broadband access - Definition and Overview

Broadband Internet access, often shortened to "broadband Internet" or just "broadband" is a high data-transmission rate Internet connection. DSL and cable modem, both popular consumer broadband technologies, are typically capable of transmitting 512 kilobits per second (kbit/s) or more, approximately nine times the speed of a modem using a standard digital telephone line.

Overview

Broadband Internet access became a rapidly developing market in many areas in the early 2000s; one study found that broadband Internet usage in the United States grew from 6% in June 2000 to over 30% in 2003.[1] (http://www.pewinternet.org/PPF/r/106/report_display.asp) Modern broadband implementations are three to five times faster than those available at the time of introduction (such as ISDN and 56K) while costing less than ISDN and slightly more than 56K.

In general, any connection to the customer of 512 kbit/s (0.5 Mb/s) or more is considered broadband Internet. The FCC definition of broadband is 200 kbit/s (0.2 Mb/s) in one direction, and advanced broadband is at least 200 kbit/s in both directions. There is no specific bitrate defined by the industry, however, and "broadband" can mean lower-bitrate transmission methods. Some Internet Service Providers (ISPs) use this to advantage, in marketing lower-bitrate connections as broadband.

Technology and promotion

Broadband is often called high-speed Internet, because it usually has a high rate of data transmission. The actual transmission speed may be relatively slow, depending on the method used; for instance, analog modems over 600bps are technically broadband.

Domestic broadband Internet connections are typically implemented via a cable modems, or ADSL. Other technologies include bi-directional satellite satmodems and power line communication modems which use the electric grid to provide Internet access. The typical broadband connection to date, whether cable or xDSL, is configured by the ISP to run at bit rates from 350-500 kbit/s. The full rate connection for a typical cable service might be as high as 10 Mb/s; for ADSL, 2 to 6 Mb/s, limited by how long the subscriber loop is (shorter loops resulting in higher speed). In some countries broadband services operate at over 1 Mbit/s for connections to private residences. Commercial users can usually obtain higher data rates for higher subscription fees.

In practice, the advertised bandwidth is not always reliably available to the customer; ISPs often allow a greater number of subscribers than their backbone connection can handle, under the assumption that most users will not be using their full connection capacity very frequently. This aggregation strategy works more often than not, so users can typically burst to their full bandwidth most of the time; however, peer-to-peer file sharing systems, often requiring extended durations of high bandwidth, stress these assumptions, and can cause major problems for ISPs who have excessively overbooked their capacity. For more on this topic, see network traffic engineering.

As takeup for this introductory products increases, telcos are starting to offer higher bit rate services. For existing connections, this most of the time simply involves reconfiguring the existing equipment at each end of the connection.

Newer technologies for twisted pair phone lines such as VDSL and pushing fiber optic connections closer to the subscriber in both telephone and cable plants are opening up the possibility of higher performance for streaming data, such as audio and video streams. There are now many streaming audio services, and several streaming video services. Broadband Internet access also facilitates the use of file sharing software.

In a few of the many areas not served by cable or ADSL, community organizations have begun to install Wi-Fi networks.

The data rates on most broadband services still do not suffice to provide good quality video, as MPEG-2 quality video requires about 6 Mbit/s for good results. Adequate video for some purposes becomes possible at lower data rates, with rates of 768 kbit/s and 384 kbit/s used for some video conferencing applications. The MPEG-4 format delivers high-quality video at 2 Mbit/s, at the high end of cable modem and ADSL performance. The Ogg Tarkin format is intended to deliver similar performance.

On August 13, 2004 the ISP Wanadoo were told by the Advertising Standards Authority to change the way that they advertised their 512 kbit/s broadband service in Britain, removing the words "full speed" which rival companies claimed was misleading people into thinking it was the fastest available service. In a similar way, on April 9, 2003 the Advertising Standards Authority ruled against ISP NTL, saying that NTL's 128 kbit/s cable modem service must not be marketed as "broadband".

The competition between the major broadband Internet providers in Canada has recently caused frequent increases in the available bandwidth provided to home users. As of May 2004, a standard broadband Internet package provides 3.0 Mbit/s downstream and 300 kbit/s upstream rates for both cable- and DSL-based services. Some residential service providers (such as Cogeco (http://www.cogeco.ca/) or Rogers (http://www.rogers.com)) offer speeds of 5 Mbit/s or higher.

In Ireland, the telephone monopoly Eircom resisted the introduction of broadband because they were making so much money from per-minute billing on 56K dialup. A consumer pressure group, IrelandOffline, was set up which was successful in convincing the government to force Eircom to introduce flat-rate dialup billing. This set the stage for the introduction of true broadband services by other ISPs (and then Eircom). Because Eircom had not invested in modern telecommunications infrastructure, however, most localities in rural Ireland are unable to get DSL over copper. The Group Data Scheme Society, an Irish cooperative, has organised to help local communities set up their own internet networks whether with wireless or other technologies.

In Sweden household broadband is mainly available through cable and xDSL, but in many places also through copper Ethernet LAN networked via fibre MANs connecting buildings. Symmetric broadband Internet access of 100 Mbit/s is available for USD 54 a month, as of november 2004.

As the bandwidth delivered to end-users increases, the market expects that video on demand services streamed over the Internet will become more popular, though at the present time such services generally require specialised networks.

Increased bandwidth has already made an impact on newsgroups: postings to groups such as alt.binaries.* have grown from JPEG images to entire CD and DVD images. According to NTL, the level of traffic on their network increased from a daily inbound news feed of 150 gigabytes of data per day and 1 terabyte of data out each day in 2001 to 500 gigabytes of data inbound and over 4 terabytes out each day in 2002.

External links

• Broadband Industry Structure (http://www.sims.berkeley.edu/~bigyale/BroadbandIndustryStructure.ppt) - PowerPoint presentation about broadband business models, technology and pricing.
• Broadband Fact Sheets (http://www.fact-sheets.com/internet-technology/broadband/) - Gives an overview of the different broadband connections available to consumers.