Broadband
Broadband in telecommunications is a term that refers to a signaling method that includes or handles a relatively wide range of frequencies, which may be divided into channels or frequency bins. Broadband is always a relative term, understood according to its context. The wider the bandwidth, greater is the information carrying capacity. In radio, for example, a very narrow-band signal will carry Morse code; a broader band will carry speech; a still broader band is required to carry music without losing the high audio frequencies required for realistic sound reproduction. A television antenna described as "normal" may be capable of receiving a certain range of channels; one described as "broadband" will receive more channels. In data communications a modem will transmit a bandwidth of 64 kilobits per seconds (kbit/s) over a telephone line; over the same telephone line a bandwidth of several megabits per second can be handled by ADSL, which is described as broadband (relative to a modem over a telephone line, although much less than can be achieved over a fibre optic circuit, for example).
Broadband in data communications can refer to Broadband Networks or Broadband internet and may have the same meaning as above, so that data transmission over a fiber optic cable would be referred to as broadband as compared to a telephone modem operating at 600 bits per second.
However, broadband in data communications is frequently used in a more technical sense to refer to data transmission where multiple pieces of data are sent simultaneously to increase the effective rate of transmission, regardless of actual data rate. In network engineering this term is used for methods where two or more signals share a medium.[citation needed]
The various forms of Digital Subscriber Line (DSL) services are broadband in the sense that digital information is sent over a high-bandwidth channel above the baseband voice channel on a single pair of wires.[citation needed]
A baseband transmission sends one type of signal using a medium's full bandwidth, as in 100BASE-T Ethernet. Ethernet, however, is the common interface to broadband modems such as DSL data links, and has a high data rate itself, so is sometimes referred to as broadband. Ethernet provisioned over cable modem is a common alternative to DSL
The Broadband Revolution
The International Telecommunications Union recently issued a press release announcing with joy the release of “the first set of global standards for Internet Protocol TV (IPTV).” A key sentence:
A combination of voice, Internet and video services over a single broadband link and from a single provider is foreseen as the ultimate goal of the broadband revolution.
Those of you who lived through ‘What Is Broadband Good For?’ with me last summer (first post here) know that the word “broadband” is a pet bugaboo of mine. It’s a word that answers a lot of policy questions in a particular way. It connotes (and denotes) a speeded, managed “service” that happens to use the Internet Protocol but is ultimately completely within the discretionary control of the network provider. So when the ITU talks about “the broadband revolution,” they mean (I think) the rise of these speeded, managed “services” provided by telephone companies. And the stated goal—made express in this press release—is to combine “services” over single broadband links and “from” a single provider. Revolutionary! Remarkably similar to cable television with a cellphone overlay.
I’m not going to say “I told you so,” but this is why the AT&T/BellSouth merger conditions a year ago were not unmixed great news. I said at the time (so I guess I am saying I told you so) that AT&T’s promise as part of that merger to keep its “wireline broadband Internet access service” neutral didn’t actually cover its planned IPTV service, which it calls its “AT&T Yahoo! High Speed Internet U-verse Enabled” service. That won’t be neutral—ever—unless things change rather dramatically in this country. I think consumers will be offered “internet” as *part* of their subscription to IPTV, IPTV will definitely affect “bandwidth management,” and “internet” won’t be what we thought it was.
