Talk:Broadband

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[edit] Possible dup

Should this page be merged with Broadband Networks? The Broadband Networks article seems to be somewhat more broad, but although it's well-written I don't really know where it belongs. Can anyone help with this? Deco 02:20, 24 Mar 2005 (UTC)

[edit] Broadband, the Band

Broadband is the name of a post-punk band out of NYC. http://www.broadbandtheband.com/ We would need to create a new page for the band and provide a link to it from this page.

That depends; is the band notable? Veinor (talk to me) 04:26, 26 January 2007 (UTC)

[edit] Broadband Doubts - Clear With Ramamurthy DWL, Amijikarai

Dial up modem isnt broadband... who say than is broadband? The fact is than dial up is until 56 K and you cant talk while use internet. Cant transport 2 signals at same time.

Ever heard of Voip ? a functionality that allows you to make voice call over the Internet. This will then means, 2 mediums on 1 network in this case dail-up.... (Nabster , Florida University of Technology) —Preceding unsigned comment added by [[User:{{{1}}}|{{{1}}}]] ([[User talk:{{{1}}}|talk]] • [[Special:Contributions/{{{1}}}|contribs]])

But you aren't really sending two signals (analog voice and digital Internet) on one line. It's like having two separate drinks vs mixing them into a single glass. 205.206.207.250 04:30, 15 June 2007 (UTC)

Dial-up using a 56k modem is known as narrowband... —Preceding unsigned comment added by 82.46.6.13 (talk) 00:22, 2 May 2008 (UTC)

[edit] Definitions of "broadband" and "baseband"

I'm a comms engineer, and I've never seen "broadband" and "baseband" defined as in the Introduction section.

As far as I've seen, "broadband" refers only to the transmitted bandwidth, and doesn't in itself imply frequency-division multiplexing or duplexing (although of course these become easier the broader the bandwidth is).

I've never seen "baseband" defined as an antonym to "broadband"; instead, it's usually used to refer to signals centred around (or very near to) 0 Hz; all the definitions in the baseband article agree with this. "Baseband" doesn't imply anything about the bandwidth of a signal. "Baseband" is technically the opposite of "passband" (i.e. a signal that has been modulated onto a carrier significantly higher than the original bandwidth), and says nothing about whether multiplexing/duplexing has been used. For instance, the baseband signal for an OFDM system is multiplexed. As another example, ethernet is baseband, but clearly multiplexes users using CSMA/CD.

Could someone provide an authoritative technical reference that defines these terms the way they are defined in the article? Otherwise, some editing may have to be done... Oli Filth 11:50, 9 December 2006 (UTC)

[edit] Permission to Include External Link

Hi, I'd like to include the link below to the Broadband Knowledge Center at Computerworld.com - -

[edit] Physics Contexts

This article should mention somewhere the widespread use of the term "broadband" in Physics contexts, such as phenomena or sensors that detect a large swath of the electromagnetic spectrum, as well as bands of electron energy levels. Chrisbaird.ma

[edit] Clarification

All right, baseband is not the opposite of broadband any more than monorail is the opposite of railroad; the term opposite is not apt, and should be reworded to reflect two modes of networking that involve a single channel and multiple channels. But, although I am very old and frail, and have not read tech reference tomes for some years, I am sure that broadband back then did not imply anything directly concerning bandwidth except to the extent that whatever bandwidth the medium provided was divided among multiple channels. Many of the definitions and examples in the standing definition of broadband are confusing, nonsensical or incomprehensible; e.g., the business about a narrow bandwidth radio signal carrying Morse code and a higher bandwidth needed for voice or video. This sort of fuzzy thinking feeds the tragic misuse of broadband to mean "high-speed." The important distinction in the new definition is that broadband channels' signals are discrete and independent; this is not the case with Ethernet, which uses a single set of transmission protocols to support multiple nodes on a monolithic bus or star network; this is not multiplexing in the traditional sense of the term. If you can run a CATV signal on the same wire, then you're talking broadband; but you'll need a cable modem or router to split out the Ethernet packets for Ethernet nodes.

The article certainly leaves a lot to be desired (see my comments higher up this page); however, IMO your edits today made things worse. I will repeat the salient points I made further up, and add some more:
  • In traditional technical usage, "broadband" traditionally refers to a broad bandwidth, and is essentially a synonym for "wideband". "Broadband antenna", "broadband noise" and "broadband equalization" are three example usages.
  • Whilst broadband/wideband doesn't always lead to high-speed transmission, in simplistic terms, data capacity is proportional to bandwidth. Therefore, although "broadband" isn't a synonym for "high-speed", the two often go hand-in-hand.
  • "Baseband" has a relatively precise technical meaning; it refers to signalling methods centred at or close to 0 Hz (DC), such as Ethernet, as opposed to a modulation scheme that utilises a carrier significantly higher in frequency than the signal bandwidth, a "passband" system. "Baseband" may also refer to the signal processing that occurs in transmitters/receivers, where the high-frequency signal is represented as a signal that centred at or close to 0 Hz, before being modulated onto the carrier.
  • The term "baseband" doesn't necessarily imply anything about the number of (frequency) channels being used. Baseband OFDM systems exist; ADSL is a good example of this. OFDM works by splitting the data into mutiple parallel frequency channels.
  • Equally, "broadband" (by its traditional usage) implies nothing about the number of frequency channels or users; simply the bandwidth available.
  • Ethernet can quite easily be considered as a form of multiplexing (statistical multiplexing, to be more precise). Any standard definition of multiplexing is along the lines of "combining data from multiple users/sources via a shared medium".
  • By saying "discrete and independent", I guess the distinction you're aiming for is "frequency multiplexed", as in any multiplexing scheme, the sources will be discrete and independent.
However, after saying all this, I do concede that technical terms do sometimes get adopted for other uses, and that many people may understand "broadband" to mean "multiple signals at different frequencies that can be separated out".
Oli Filth 21:53, 8 June 2007 (UTC)

[edit] Disagree with Oli Filth

I fundamentally disagree. I came to this page to try and settle an argument about whether people are misusing the term broadband. I expected WP to be an authoritative source on such a technical topic, but I just ended up depressed about the future of the project.

Recently the term is often mis-used to refer to the bandwidth, but it's correct meaning is connected with multiplexed signals (traditionally in the frequency domain). The antonym is baseband where only one signal is transmitted in the medium.

I think it came to be mis-used because DSL and cable Internet are transmitted using frequency-division (i.e. "broadband" in the correct sense of the word), and people heard the term and assumed it meant "high speed". The word you're looking for is perhaps wideband.

Baseband OFDM systems surely don't exist, by definition. And ADSL is precicely not an example of baseband. The voice component on a phone pair is baseband and the DSL overlay frequency bins are broadband.

Right now, this article reads like two groups of people chipped in with text, some describing broadband and some wideband. It's one of the ugliest and technically-misleading articles I've read in a long time.

Of course, Oli graduated recently and my Cybernetics degree is over 20 years old (eeek). So my memory of this stuff is a bit rusty.

I went looking for cites and found these:

Not a selective list, either: basically the first few useful Google hits for the search term broadband baseband ... richi 00:21, 24 August 2007 (UTC)

Hi! Here are my thoughts (sorry for the length of this reply!):
  • As I've said previously, in comms engineering (certainly in the subset that I inhabit!), "broadband" is used in contexts that have nothing to do with multiplexed signals); the examples I gave were such as "broadband equalisation" and "broadband antenna".
  • Whether we regard "broadband" to be a synonym for "wideband" or "FDM", the traditional use of "baseband" is certainly not its antonym! Traditionally, "baseband" has a relatively precise technical definition; none of these definitions says anything about the number of channels (in this regard, I consider the Baseband article fairly accurate, except for the recently-added section at the end!). "Baseband communication" is, as far as I'm concerned, the antonym of "passband communication" (i.e. where the signal has been mixed up significantly, such as a radio transmission).
  • Although I can't prove it (without doing an exhaustive search of all available literature!), I would guess that the "misuse" of the terms actually occurred the other way around. Hypothesising, broadband systems (in the traditional sense) are capable of carrying multiple FDM channels, therefore "broadband" has come to mean "FDM". Equally, baseband systems (such as Ethernet) are generally not FDM, hence "baseband" has come to mean "not FDM", and therefore (very loosely) an antonym. In my opinion, this would be like saying that "car" is the antonym of "duck", because cars can't fly.
  • As a comms engineer, I would consider ADSL a baseband transmission scheme. Whilst it's true that it doesn't extend all the way down to DC, this is more a case of the low-frequency sub-channels being switched off (i.e. there is nothing to stop generation of sub-channels all the way down to DC). The general rule of thumb is "does the signal require mixing up to its centre frequency"; for ADSL the answer is no.
  • I'm afraid that I have to say that some of those references are pretty incoherent! e.g.:
    • "A baseband transmission is carried over a single wire using digital signaling... Broadband transmissions are analog transmissions."[1] All transmissions are analogue in that they use an analogue medium; it's the nature of the data being transmitted that determines whether it's a digital or analogue system.
    • "Broadband - A type of data transmission in which a single medium (wire) can carry several channels at once."[2] This definition would encompass all of TDM, FDM and CDM (and any other multiplexing scheme one could think of).
    • "Baseband - Bi-directional transmission ... Broadband - Unidirectional transmission"[3] - What does directionality (or duplexing) have to do with anything?
    • "Baseband - Signal travels over short distances ... Broadband - Signal can travel over long distances before being attenuated"[4] - What does propagation distance have to do with anything?
    • "the cable modem is using a broadband service, because it is connecting to a signal that is riding on the cable, rather than to the cable itself."[5] What is that supposed to mean?
Whilst I'm willing to concede that other uses for these terms have sprung up, and that we should probably give credence to these alternative definitions in the article, I think it's essential that we only include them once we've found a relatively coherent definition, and that we illustrate them in the proper context (i.e. that they are an offshoot of the traditional engineering "definitions", as fuzzy as those are), and only with proper references. In a nutshell, we have to distinguish between things that are merely characteristics of typical broadband systems, and things that are considered fundamental to the definition of the term. Oli Filth 12:10, 25 August 2007 (UTC)
I've dug a little deeper; a brief Google Scholar search turned up papers and patents from the 1940s that use the term "broadband", essentially in the sense that I contend it's used for [6]. Oli Filth 12:47, 26 August 2007 (UTC)
Also, the textbook "bible" for comms engineers, "Digital Communications" by J.G. Proakis, also uses "broadband" in this sense; this book has been around for some 25 years or so. Oli Filth 15:26, 27 August 2007 (UTC)

[edit] "Cable Broadband" vs ADSL

I removed the line from the introduction about Cable Broadband in relation to ADSL. It doesn't seem relevant to this section - maybe more suited to the article on broadband internet types. (I meant to add this comment to the edit summary, but accidentally hit Enter a bit too soon...) 4.249.45.242 15:35, 12 June 2007 (UTC)

[edit] See Also: Flat Rate

I deleted the See Also link to Flat Rate (which redirected to Flat Fee) as I cannot see any relevance to the article. There is a mention in Flat Fee about broadband internet pricing schemes, but the Broadband article is not specifically about internet access, and there is no other mention of pricing before the Flat Rate link. 4.249.45.242 15:46, 12 June 2007 (UTC)

[edit] Typo

Do you mean "... although much more than that can be achieved ... " in the first paragraph.

That's about what it means, but it's correct as stated. Dicklyon 06:13, 15 September 2007 (UTC)

[edit] HISTORY

THERES ABSOLUTELY NO HISTORY OF DSL IN THIS ARTICLE. NOT A SINGLE DATE —Preceding unsigned comment added by 24.188.17.249 (talk) 22:20, 23 February 2008 (UTC)

  • That would be because this article isn't about DSL ... richi (talk) 16:53, 25 February 2008 (UTC)