Misuse of the term 'Broadband'

[Floid]

Broadband (BB)
    Broadband (BB) is: (1) Transmission equipment and media that can support a wide range of electromagnetic frequencies. (2) Any voice communications channel having a bandwidth greater than a voice grade telecommunications channel; sometimes used synonymously with wideband. (3) Typically the technology of CATV (QV) transmission, as applied to data communications; It employs coaxial cable as the transmission medium and radio frequency carrier signals in the 50 MHz to 500 MHz range.
Broadband ISDN
    Broad band ISDN is the second generation of Integrated-Services Digital Network (ISDN) that provides transmission channels capable of supporting rates greater than the Primary ISDN rate.

From http://education.icn.siemens.com/doc/jobaids/glossary/test_B.htm, which is reasonable enough.  The common 'abusage' stems from (2), and a particular old Bell System technology/offering I can't find a proper reference to.  (Basically, if you needed to perform a long-haul telecast, or something else that wouldn't cram onto a voice circuit, you had to get time on a 'broadband' trunk or somesuch thing; literally something like a really long piece of coax with nobody else sharing it.)

Today... well, every 'broadband' service does probably signal in a swath 'wider' than a voice channel (which is only a few KHz), but the topologies are wholly different than what the telcos could imagine a decade ago.  (Cable and DSL only have to handle the 'last mile,' at which point everything is just packet-switched onto fiber.  The first try with ISDN, among other things, made the mistake of trying to route packets to the user's ISP -- which dramatically increased complexity in a big country like the US -- DSL 'sanely' just drops off some wires at the RT or CO, and makes the providers plug in their equipment there.  Cable's still allowed a quasi-monopoly, at least over here, so it's not a big deal for them.)

Note that everything in the real-world is analog, at least until you get to the quantum level.  Modern signaling techniques aren't simple voltage swings, but that's not what makes something 'digital;' 'digital' just implies a sort of noise-reduction technique, wherein you only concern yourself about extracting two states, in the hope that you can 'easily' detect/correct errors and do other nifty things.  If you look at what actually goes on inside a CD player (especially one with a "1-bit" DAC), it'll blow your mind.

[Floid]

Lo wrote:
I prefer the term "WideBand" but ...

Another one is "Digital Speakers!"  :lol:

There are actually USB speakers around (more common in the days just before AC97 broke out on everything), where the speaker housing contains a DAC and whatever associated USB peripheral junk makes it happen.

[Floid]

darksun9210 wrote:
ok. my basic understanding of "broadband"

broadband's basic specification is 2.2mb (megabit) download speed, as this is the minimum bandwidth required for a full stream, full motion video, digitaly compressed TV. the upload speed is based on the providers discretion.

This could be the legal/regulatory specification in a particular area, sure.

this is why providers are able to offer "business 2000" 2mb links and charge the earth, when it is using the same hardware as for the "home 500" 512kb link. its all capped in software at the providers end. just they want more cash for opening the taps a little more on your connection speed

In the US, they have to worry about bandwidth costs; not so much in terms of whether the capacity's available, but whether they'll be able to show a profit.  No idea how the money flies for the peering arrangements in the UK, but just as US telcos once flopped and wavered over the idea of supporting all the extra data traffic over fiber deployed with voice in mind, I get the impression BT isn't hot on the expense of upgrading... whatever needs upgrading.

thing that REALLY REALLY gets me, is, i want a nice fat 2mb link, even 512kb would be nice. and i see adverts for broadband every second advert, and i would gladly pay for it
/me waves money at BT
(maybe even quit smoking to afford it :lol:  :lol: )

but i too far from a broadband exchange to get a reliable adsl signal = not in a broadband area. i even had to shout at BT to turn up the gain on the phone link as my DIAL UP connection signal was too weak. :pissed: hey guys! ever heard of AMPS?  :pissed:  :pissed:  :pissed:  

How's the old analog Advanced Mobile Phone Service going to help?

Nah, seriously, the way SBC solved this (and generally all DSL-provisioning ILECs do here; I just had to keep track of SBC because they're my local carrier) is by deploying "RT"s.  The "Remote Terminal" is a big box on the side of the road that acts as a remote "Central Office;" pairs from the neighborhood terminate at it, and everything runs over new fiber or possibly high-speed copper back to the CO.  Apparently the idea is to drop one atop/next-to an old cable, so you can just splice all the customers on that cable in without anyone noticing.  (At my old residence, you could actually see the old copper cable to the CO chopped off at the ground, all its hundred pairs or so now visible and open to the weather.)

So in a sense, the RT is a giant copper-to-fiber (or whatever the telco uses for mid-haul networking) bridge, with room for DSLAMs and all else (so DSL users' data packets ride as data packets -- probably IP or PPP over ATM -- from the RT, and get routed to the various ILEC and CLEC backbones at the CO... I think.)*  It doesn't make sense to just amplify the pairs, because while that might work for voice, it'd be just as expensive to deploy low-noise amplifiers that'd work for both current DSL and whatever improvements are invented down the line... and probably a good bit more fiddly.

SBC in particular went on and on about how impossible things would be, then when the accountants' math worked out unveiled "Project PRONTO" (something you'd never hear of if you weren't a DSLReports user), and got majorities of area in their DSL-less states covered with RTs in about three years.  (You now get better service in those states than outside of them, since, of course, all the equipment is the same, just like Ma Bell.)  From what I hear of BT, they're playing some interesting 'petition' games to ensure they'll never have to deploy RTs anywhere that won't pay the cost for them.  (Guess the "universal service fee" here does count for something, as IIRC RTs do count as a voice provision for rural users, and SBC could dip into the fund to make it happen.)

I hear users in some areas of Jersey or Philly are screwed, because whoever is/was incumbent down there deployed RTs for voice just before DSL hit it big ("info superhighway" days), and strung juuuust enough fiber to replace their voice capacity, while all that equipment still has to depreciate... Oops.  Those could probably provision ISDN, but ISDN has a crazy stigma over here, and the telcos used to push back the costs of line provisioning (similar to those for DSL - clearing bridge taps and loading coils, getting rid of obsolete trunking systems in favor of RTs or copper straight to the CO) onto the early adopters -- meaning you could pay into the thousands just to have the line 'installed.'  (These days, 56k or 128k shared with voice just isn't compelling to most people, and it's probably cheaper for everyone to deploy that level of service over wireless!)

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*Dunno what the politics are for CLECs (and/or what the ILECs are required to provide to the CLECs)... it'd make sense to ride everything over ILEC fiber and sort it out with routing at the CO, but the CLECs might have to rack their own equipment in the RTs and lease capacity back to the CO (or run their own fiber to their office).  

[Floid]

AmigaFreak wrote:
Anyone used DSL before? My friend used to have it and it was horrible! horrible horrible horrible!

As noted above, the particular type of service I've got from SBC is kicking some a$$, though their billing is definitely getting more confusing than it needs to be lately (attention SBC accountants: If you want $60-$70 from me a month, just call the voice portion $30 and the DSL $30... I don't need voicemail!)...  I get 1.5mbit/s down, and supposedly they've just bumped it to 256 or 384kbits up, though there's PPP overhead on all of that.

DSL can get screwed up in about four ways; they can bugger up the lines (bad copper, unremoved bridge taps and other oddities, no RTs where they need RTs); they can deploy faulty or flaky modems (friends out in Qwest territory are onto their third ActionTec; the first Efficient models SBC deployed would die, apparently... as 90% of people get their hardware with the service, there's none of that competetive incentive to make things stop sucking quickly, and since it's a new technology, it took a while for people to figure out what 'normal' was supposed to be); they can screw up at the headend (encompassing all of crappy pricing, flaky routing, oversold bandwidth, poor maintenance procedures that kill people's connections needlessly)... and finally, Windows can be screwed up!  ('98, by default, will only get like 8k/s out of a high-latency/high-'bandwidth' link if you're lucky... check that TCP receive window!)

All those problems can equally befall cable, but the 'advantage' of cable is that, if they screw up on the physical end, chances are *all* their customers are going to notice... and it is a bit needless for some providers to deploy PPP when they could just let the DSLAM sort out plain ethernet frames.  (Apparently SBC does PPP because it's easier to use the same authentication on everything --  the service comes with a dialup account for backup/travel -- even though DSL, being physically-apportioned, doesn't really need authentication at all; they can just rip the proverbial wires out.)  Both DSL and cable technologies are really about as 'neat' as ethernet (if not moreso; after all, they handle plain old wiring 'magically'), and both should perform about as well (given the limitations of the wiring and topologies) when deployed right.

[Floid]

whabang wrote:

Oookaaay...
Well, the DSL-technologies use analogue lines to transfer data. AFAIK, it's possible because they use much higer frequencies than an ordinary modem. Don't quote me on that, though.

It's all just copper, whether it's in your printer cable or strung up down the street.  The voice service (using low frequencies on the lines) is as analog as it ever was, because DSL has nothing to do with the voice service*... Which is to say, 'very' from the handset, and not so much once you hit the ADCs at the modern digital switch or the RT.

*Until you throw out the voice service on the line, and switch to VoIP.  Of course, very few companies will dare provision "naked" DSL.

[Floid]

Lo wrote:
Wow, 'ol Floid knows his DSL, thanks for da info.. and digital speakers? ?

There are actually USB speakers around (more common in the days just before AC97 broke out on everything), where the speaker housing contains a DAC and whatever associated USB peripheral junk makes it happen.

It had to happen!  Aaarghh!  :pissed:  I am going to retire! (Wait, I am already retired and replaced by some satellites! Arrrgh!  :pissed: )

Not only that, they're obsolete already (as noted; the analog resurgence and the brief 'everyone needs a SBLive even though they'll never take advantage of it' fad killed them)... Here's a set based on the same drivers (pardon the pun) as my analog setup, though you can only find them in the closeout market these days.  (Actually, the same model number apparently came in a mini-DIN SPDIF? version, and heck if I know what's actually pictured in the thumbnail.  The reviewer obviously had the USB model, and missed the rubber feet that came in the box. )  The Griffin iMic, and some 'audiophile' products that are just the same thing in a fancier case... are, er, the same thing minus the speakers.

Who wants to be the one to hand sir_inferno a photocell and an audio amplifier?

[Floid]

that_punk_guy wrote:
....I'm confused, what's wrong with saying "CD-ROM"??

Absolutely nothing, as ROM itself stands only for "Read Only Memory" (though Phillips may or may not have used 'Read Only Media' in their lit, same difference) ... Presumably there's some protest as to the way the information is addressed (for instance, CD, whether -ROM, -R, -RW, or -DA, was never quite designed for random reads), and it's right we should remember that shiny laser-read LPs are not the only route we've found to data storage,* but nobody ever said read-only memory had to be directly accessible ... and there have probably been some competing technologies for blowing ROMs in silicon, as well.**

*Though the spiraling that makes CDs (and MOs!) a bit weak for random access in trade for density has now apparently snuck into hard drives... and there are various ways to trade it off such that you'll never notice in practice.

**I'm fairly certain there are, but I forget the names now.

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If I remember right, the whole DVD+/- fiasco hinges on both on-disk formats (+ supports Mt. Rainier, or the DVD equivalent, while - perhaps doesn't?) and differing dyes for the physical media, prerogative of the keiretsortiums backing each.  -RAMs were backed by a third party, came in caddies, and were incompatible with everything.  [IMHO, yet another reason not to get too attached to the 8-tracks in favor of whatever will obsolete them, but then, I'm just not kewl like that.]

[Floid]

iamaboringperson wrote:
BTW, the problem I have with the term 'CD-ROM' is that since CD's were released, THEY HAVE ALWAYS BEEN READ ONLY. Why append -ROM to CD? There is actually little difference.

'Read Only' is redundant!

ROM has always stood for Read Only Memory. When 'CD-ROM' was first used, the ROM part stood for Read Only Memory.

The -ROM part was apparently the idea of some marketing guru who had very limited computer knowledge, and was only used in one country for a while and then it spread world-wide.

I say 'CD', it's so much easier!

Well, the words "Compact Disc" themselves don't say much beyond "disc, relatively not-big."  "CD-ROM" is defined by a separate set of standards (Yellow Book) from CDDA (Red Book), and a redbook CD is poorly suited to acting as a data ROM because "-DA" didn't actually have to worry about bit-accuracy (more like probabilistic accuracy).*  So they did have to define some sort of new standard to, er, standardly use the medium defined in the Red Book for data... and since that standard was designed to allow CDs to function as bit-accurate Read-Only Memory, it deserves the name.

With Phillips as the arbiter of all things "CD," it's little different than Sony branding "MD Data."  A little redundant, but their prerogative, and without such specs there were no specs for using either medium for bit-accurate 'read-only' operations.  (In other words, whence previously you had 'recordings,' you could say the data specs raise the bar to 'memory' levels of tolerance.  Even the 'recording' technology probably performed a hell of a lot better than old drum memory, see below.)**

You're perfectly welcome to call it a "CD," you're just not being specific. ;-)  Phillips left the semantic door open wide enough to be able to release a "CD-Analogue" or "CD-Random Noise Generator" if they ever had the need, which was actually sort of smart.  (It was the '80s, after all- who could've foreseen the SmartMedia-to-floppy adapters, and on the same token, who would've predicted that there wouldn't possibly be something similar in the optical domain?  They were just out to create a shiny improvement on the LP, when they started...)

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*Of course, you *can* use a redbook CD with alternate error correction/error tolerance technologies; hipsters today are backing up old Atari and Commodore tapes to Red Book CDDA, and the noise tolerance to those low-bitrate encodings lets them function as well as they did from the original media; similarly, there are a couple ways to add error correction to the bitstream on the disk itself, and since Yellow Book was to some extent cobbled-up "after the fact," there are a few competing ways of doing it allowed.  You could come up with your own incompatible method, but then it wouldn't be a "CD-ROM."  :-o

**Actually, for all I know, bit-accurate duplication was part of the original MD spec, at least.  But barring the 'official' designations, neither Phillips or Sony would've given you any sort of guarantee on the sanctity of their designs for data operations.  Semantic wanking, but also what counts; you can't use something that "doesn't exist," though in turn I do think Yellow Book "took back" under Phillips' mantle a number of hacks that worked fine before anyone thought to worry.

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Now if you want to point out things-pathetic, it's disappointing to see Sony coming up with BS like "NetMD" after killing and burying the first "MD Data" spec.  Not only can they not manage to pretend things are somehow related or compatible (and they're not; they screwed up too badly at first), but the new branding doesn't even have anything to do with anything; it's as if Chrysler/GM/whoever were to start marketing a "fission car" because they think their latest 4-cylinder is just that good. :destroy: