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How Broad is Broadband?
Photon01 writes "The Register reports that UK ISP NTL have lost, in a ruling that their advertisement of their 128k broadband service as 'High Speed Broadband Internet' is misleading.
This is despite it clearly meeting the technical definitions of broadband internet.
Apparently 128k broadband is not broad enough." My first cable modem was only 256k. It wasn't blazingly fast but after being stuck on dialup it was heaven, and I imagine 128k wouldn't be so bad for a single household.
This is what comes of marketting departments taking a technical term and redefining it. The opposite of broadband is not narrowband, but baseband (eg the defunct V.35).
What can be done to stop sales and marketting (and politicians) from diluting perfectly good technical terms.
13.21 Gbps OC-255
10 Gbps OC-192
4.976 Gbps OC-96
2.488 Gbps OC-48, STS-48
1.866 Gbps OC-36
1.244 Gbps OC-24
933.12 Mbps OC-18
622.08 Mbps OC-12, STS-12
466.56 Mbps OC-9
155.52 Mbps OC-3, STS-3
100 Mbps CDDI, FDDI, Fast Ethernet, Category 5 cable
51.84 Mbps OC-1, STS-1
44.736 Mbps T-3, DS-3 North America
34.368 Mbps E-3 Europe
20 Mbps Category 4 cable
16 Mbps Fast Token Ring LANs
10 Mbps Thin Ethernet, category 3 cable, cable modem
8.448 Mbps E-2 Europe
6.312 Mbps T-2, DS-2 North America
6.144 Mbps Standard ADSL downstream
4 Mbps Token Ring LANs
3.152 Mbps DS-1c
2.048 Mbps E-1, DS-1 Europe
1.544 Mbps ADSL, T-1, DS-1 North America
128 Kbps ISDN
64 Kbps DS-0, pulse code modulation
56 Kbps 56flex, U.S. Robotics x2 modems,
33.6 Kbps 56flex, x2 modem communications rate
28.8 Kbps V.34, Rockwell V.Fast Class modems
20 Kbps Level 1 cable, minimum cable data speed
14.4 Kbps V.32bis modem, V.17 fax
9600 bps modem speed circa early 1990s
2400 bps modem speed circa 1980s
Units of Measurement
bit = smallest unit of digital information, i.e. ones & zeros
byte = a set of bits
bps = bits per second
Kbps = kilobits per second =1000 bits per second
Mbps = Million bits per second =1,000,000 bits per second
Gbps = Gigabits per second = 1,000,000,000 (one billion) bits per second
Tbps = Terabits per second = 1,000,000,000,000 (one trillion) bits per second
(Network speed is mesured in 1000 units, memory and storage space in 1024 units)
2 definitions found
:
:
From WordNet (r) 1.7
broadband
adj 1: of or relating to or being a communications network in which
the bandwidth can be divided and shared by multiple
simultaneous signals (as for voice or data or video)
2: responding to or operating at a wide band of frequencies; "a
broadband antenna" [syn: wideband]
From The Free On-line Dictionary of Computing (09 FEB 02)
broadband
A transmission medium capable of supporting a
wide range of frequencies, typically from audio up to video
frequencies. It can carry multiple signals by dividing the
total capacity of the medium into multiple, independent
bandwidth channels, where each channel operates only on a
specific range of frequencies.
See also baseband.
(1995-05-09)
It's not how much you have have, it's how you use it.
Broadband means it's a communications channel divided into multiple chunks. Each person on a cablemodem connection uses a different freqency range on the same cable, that makes the cable broadband. The opposite of broadband is baseband, that's where the base comes from in 100BaseT.
If you divide a 2400 baud modem among several users in that way, it can be called broadband too even though each user only have a few hundred bps.
Jason
ProfQuotes
Bandwidth makes zero differences when determining if a system is "broadband" or not.
Broadband only refers to the transmission method, not the throughput. All that "broadband" means is that multiple, independant network carriers are multiplexed onto a single wire. That's the definition of "broadband". Your other option is
"baseband".
Anyone who argues that ADSL isn't broadband is either ignorant of the meaning of the word, or ignorant of the technical details of DSL.
by Mike Buddha -- Someday the mountain might get him, but the law never will.
If you're connecting via an ethernet port, it ain't broadband, my friend. Ethernet is a baseband network. Your school may be connected to the Internet via a broadband connection, but if you're using ethernet, you're using baseband.
by Mike Buddha -- Someday the mountain might get him, but the law never will.
It's not clear how this term became associated with DSL. Early on, DSL was referred to as "data over voice". (This came from the old "data under voice" system, which sent very low data rate signals for alarms and such over lines also carrying voice, using a frequency band somewhere below 100Hz.) Both of those terms are now obsolete.
DSL has no DC component (you can put it through a capacitor and it works just fine) so technically, it is "broadband". But that has nothing to do with the data rate.
From a regulatory standpoint, what we need is this: It is deceptive advertising to advertise an "up to" speed without showing, with equal or greater prominence, a guaranteed minimum speed. This rule should apply generally to any advertising that specifies some numeric measure of goodness.
Gbit Ethernet doesn't function over Cat-5(e), as Cat-5 maxes out at 100Mhz full-duplex and Cat-5e maxes out at 350Mhz full-duplex. For full-speed Gbit Ethernet over copper you need Cat-6.
Another one I see that he left out is ATM - which works at the same speed as an OC-3 (155.52 Mbit/s). Still... a pretty complete listing, over-all.
/dev/random
However, for reaching further from the CO, it is possible to do IDSL. It is 144k/144k symmetric, and is often marketed as a "business" class service. Therefore it has a business SLA, and often comes with a router and multiple static IP's. For example one major ISP sells it with a /29
I am involved in the videogames industry. In this generation of consoles, there has been a lot of controversy on the definition of broadband, since there's not a standard on the requirements for any given game and there's not a clear way for the user and the developer to know if they are met beforehand.
This causes a big problem for everybody. Developers have an inherent need to limit their bandwidth requirements and perform a lot of tests to reduce network problems, and it can really influence gameplay design; technical support and marketing can be a headache for the publisher and the experience for the user can be very frustrating if there is a simple latency problem, even if the bandwidth is high.
Every "broadband" user in this case says: "but I have broadband! Why can't I play?". Latency and bandwidth are very complex things to explain, and many factors can affect the videogame experience negatively. (number of hops, type of interface, firewalls, NATs, network traffic, just to name a few)
I performed extensive tests with the Dreamcast, the PS2, the GameCube and the Xbox, I can say not many games really require more than a 64K connection, but in many cases, while even the bandwidth of a 56K modem could suffice, a specific game may have a problem with the latency associated. That's why some games are labeled as "broadband only". Of course, it doesn't guarantee the connection will meet the game's requirements, but it minimizes the problem somewhat.
As it is, we used to have a better way of classifying the connection speed on dial-up modems. The diversity on interfaces and protocols (xDSL, Cable, WLAN, etc.) just render the term "broadband" useless.
I remember Ken Kutaragi (Playstation's main designer) saying something in a conference a couple years ago that went along the lines: "you call 1.5 Megabits/sec 'broadband'? But that's about the speed of a CDROM!" I wish Kutaragi extended the analogy to latency using CDROM seek and access time too.
We need a better way to refer to a modern Internet connection, period.
- Otaku no naka no otaku, otaking da!!!
Last time I heard, a n(yi)bble was 4 bits. Has something changed in the last fifteen years? (And yes, there is some precedent to say that it varies, but 4 bits is the most common usage...)
--ZS
-- sigs cause cancer.
It's whether 128k can be described as high speed broadband. It can't. 512k is normal broadband, 128k is their low cost, low speed broadband option and I welcome the fact that it exists but it certainly is not high speed broadband.
Government of the people, by corporate executives, for corporate profits.
Technology does. Broadband is a kind of link that can do multiple things. Like DSL, there is both data and voice riding over the same wire, just in seperate bands. This is as opposed to technology called baseband, where the whole bandwidth of teh link is used for one task. Ethernet would be an example of baseband. It is perfectly possable to have really slow broadband (like say DSL with only 64k upstream) or really fast baseband (like 10Gb ethernet).
The reason why broadband is an exciting technology to the home user is that you can get data over an existing technology like cable or phone lines. Since it travels in a seperate band, it doesn't interfere with your existing service, and since it is part of the same link, there is no requirement to run an additonal connection to your house.
However it has no bearing on speed. My external link is broadband, but only 640kbit/sec. My internal links are all baseband, and old technology at that, but still run at 100mbit/sec.
IDSL is an interesting case. IDSL is broadband. ISDN isn't.
How is this so? The various DSLs work by what is essentially an RF process, in the same way that cable modems, television channels, etc. do.
The opposite of broadband, baseband, is represented by things like 10BaseT (note the word 'base') and refers to a non-modulated signal.
As an aside, there was an early cable modem standard known as 10Broad36, from memory, which was 10 megabits with (I think) a 36 or 3.6GHz carrier signal. That's what the 'base' in 10BaseX, 100BaseX and 1000Base-XX means.
So, it's technically possible to have a really slow (IDSL) broadband connection, yet have a really fast (1000Base-ZX, good for up to 70KM over 1510nm single mode fibre) baseband connection.
Although, with the introduction of (D)WDM-style multiplexing, where several fibres can be modulated over one piece of fibre, the WDM part of the backhaul would still technically be broadband, as the various wavelengths are multiplexed onto one really clean piece of single-mode fibre at many slightly (I think they vary by about 100MHz in either direction, and the standard units are good for about 1.6GHz variance) different wavelengths.
Broadband is a meaningless term, although these days it appears to have been redefined to mean 'anything faster than 64k or so', in much the same way that hacker now means 'evil computer guy in a black hat and an Anthrax t-shirt.'
Disclaimer: i'm a network engineer, not an EE, so I've been deliberately vague about exactly how RF modulation and such actually work.
You're doing it wrong.
Latency.
An interesting term.
You're most likely getting less latency on your ISDN than people do on their various *DSLs because of the crap way that almost every ILEC implements the CMUX->3rd party ISP transition.
ISDN's theoretical minimum SRTT is ~30ms (15ms end to end.) This will vary based on your distance from the switch, and the router you're calling's distance from its switch, and the number of switches in the middle. Remember, ISDN is circuit switched, so once you've established a Q.931 call you 'own' that 64 kilobits of bandwidth until you hang it up. There's no contention (unless the router at the other end is being hammered by something and its CPU is peaking, but that's not a physical constraint.)
DSL is usually sold by LECs to ISPs in the form of an ATM circuit that plugs into an L2TP LNS (concentrator.) A PPPoE/PPPoA connection is then established between the subscriber and the LEC's DSLAM, which then, acting as an LAC (l2tp client) forwards the circuit through the ATM network into the ISP's LNS.
The issue here is analogous, but not identical, to the 'engaged signal' problem which dial ISPs had (and still have.) You only purchase so much capacity from your LEC. When the subscriber:capacity ration exceeds 1:1, you will inevitably get contention. In the circuit-switched world of dial, this results in busy signals. In the cell-switched DSL/ATM world, this results in contention for backhaul bandwidth, which causes an increase in ping times. In theory (assuming zero contention,) any DSL will be much faster than ISDN.
I'll give you some (real world) examples. On my home, majorly oversubscribed, ADSL line (which is currently unladen,) a traceroute yields this:
traceroute to 203.24.47.212 (203.24.47.212), 30 hops max, 38 byte packets
1 172.18.0.254 0.548 ms 0.231 ms 0.225 ms
2 202.59.108.248 1.092 ms 0.754 ms 6.590 ms
3 202.59.104.1 51.111 ms 41.659 ms 89.890 ms
The first 2 hops are the internal and external firewalls, respectively (yes, I am sad.) The third hop is the LNS at my ISP who shall remain nameless but is easily identifiable with a whois @whois.apnic.net.
The 2 megabit SDSL connection I've got at work, into our own equipment (I work at a small company who owns its own SDSL infrastructure, essentially a LEC in their own right,) the traceroute yields this.
traceroute to 203.24.47.212 (203.24.47.212), 30 hops max, 40 byte packets
1 203.x.y.1 0.805 ms 0.856 ms 0.705 ms
2 203.x.z.1 1.577 ms 1.298 ms 1.184 ms
3 10.144.0.13 2.583 ms 2.682 ms 2.084 ms
4 203.x.a.97 3.097 ms 1.989 ms 2.064 ms
Where, again, 203.x.y.1 (I don't plan to identify where I work in this post, because that path is fraught with danger) is the switch which separates the engineering subnet from management, wireless, and phone (which is almost invariably at 85% utilisation due to the broadcast nature of 3com NBXes). 203.x.z.1 is the SDSL router (a flowpoint 2200 if you're interested), and 10.144.0.13 is the DSLAM. There is no backhaul ATM network in this scenario because we don't have resellers.
Finally, off a friend's ISDN connection:
traceroute to 203.89.25.72 (203.89.25.72), 30 hops max, 40 byte packets
1 203.13.113.105 0.996 ms 0.855 ms 0.870 ms
2 203.13.114.255 30.416 ms 31.422 ms 30.518 ms
This network is less complex. 203.13.114.255 is the ISDN router at the ISP end. The link is unused at the moment as he's in the process of transitioning everything to an ADSL connection (oh, the irony.)
The reason your pings go to shit in a game is because you're trying to stuff too much data down your 64k line, and the buffer in your modem/router is filling up. As this happens, it takes extra time for each packet to get from the end of the queue to the start thereof. Your pings go to crap and you get kicked off the server.
Bandwidth and latency have an interesting relationship.
You're doing it wrong.
---- Den ene knappen er powerknapp, den andre er Bender voice knapp "Bite My Shiny Metal Ass"
> My ADSL connection is 8Mb/s (1MB/s). Can that be defined as broadband?
I dunno, my car is forest green. Can it then be concidered fast?
That makes about as much sense as what your asking.
Being ADSL, yes it is broadband.
It doesnt matter if you could only send 3 or 4 bytes per second, or gigabits per second, its still ADSL and thus still broadband.
The best way to ask is, is anything else served over this carrier other than IP data? In the case with DSL, its phone service. In the case of a cable modem, its TV signal. Same with satellite.
Dialup is not, because your not running both data AND phone over the phone wire. You are indeed only running phone service over that wire, because modems require phone service.
ADSL does not run OVER the phone network. It runs along next to it.
In DSLs case actually, DSL only exists between your house and the central office your service comes out of. Once it hits the CO, it turns into something else (Usually ATM, possibly just a DS3) and from there goes to your ISP. The ISP no doubt has a DS(1-3-etc) based network to their upstream and so on.
According to a letter I got today (I've got a 600k subscription), NTL are going to scrap their 128k service and replace it with a 160k one.
That's interesting enough, but what is more interesting is that my friend (who has the 128k) service tested the speed of his line and it was actually running at 250k!
This was presumably so 128k customers would tell all their friends how great NTL is, but the net result is that the speed 'rise' is actually a decrease (because I bet it'll start running at its real speed now)!
(And of course they're putting the price up too.)