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Dutch ISP Demos Symmetric 100Mbps DOCSIS3
Mark.JUK writes "CAI Harderwijk, a DOCSIS 3.0 based Cable Modem operator in the Netherlands, has apparently managed to achieve a world first by demonstrating symmetric broadband internet access speeds of 100Mbps. The tiny Dutch operator is home to just over 16000 customers and was already planning a switch onto Fibre-to-the-Home (FTTH) technology, although this may now be delayed. The test itself is important because cable operators are still, perhaps unfairly, seen by some as being inferior to fully fibre optic-based broadband services. In reality, cable operators are, for the most part, continuing to keep pace."
Carbon-based life-forms using silicon-based computing systems with copper-based communication lines. We need to break these bonds.
Torrent trackers have popped up all over the Netherlands from home 100Mbps users
It's Symmetric 100Mbps over Cable. And a sizeable number already have 100Mbps (like with UPC Fiber) but that still is asymmetric. Yes that is news.
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The notable words are "Cable operator" and "symmetric". A cable operator showed that they are able to deliver 100/100 Mbps speeds (as opposed to the 100/10, which is much more common) and generally tries to debunk the idea that cable operators are (becoming) inferior when it comes to ISPs. No "Groundbreaking news" there but I still think that TFA was a decent way to spend one minute of my life.
It's not DSL, it's cable, so using coax cables instead of telephone lines. I don't know what that means for speed vs. distance though. For your information: "CAI" is Dutch for "central antenna installation". Those cables have been laid to deliver TV signals.
Secondly "laying FTTH" of course is nice, but it's also mighty expensive and disruptive to break open all the streets and dig trenches to everyone's home. These CAI cables are there already, so why not continue to use them? Just like what DSL is basically doing with telephone lines.
When building new homes of course nowadays they should put an optical fibre in the trenches that they dig already for telephone, cable TV, water pipes, power lines, etc. Then it's a relative cheap upgrade. But for existing homes this is definitely the cheaper option.
One coax cable has a usable bandwidth of about 1GHz. All users connected to the same cable share this bandwidth. Depending on the signal-to-noise ratio, encodings, forward error correction, different effective channel capacities can be realized. In practice it's going to be about 7bits/s/Hz, so the total capacity of a coax cable is no more than 7Gbps, which of course isn't all available for internet access because people still want cable TV. At most 35 dedicated symmetric 100Mbps connections can be supplied by one coax cable, fewer if you consider technical limitations and split usage with cable TV. Hundreds of customers are typically connected to the same cable.
The main difference between DSL and DOCSIS cable is that DSL is your personal connection. No one is sharing it. DOCSIS cable line is shared between those on the same line, so if you have active warez people in your neighbourhood or someone hosting an active server of some kind, expect much lower speeds and higher latency then advertised.
Second difference, which has been largely negated lately is latency. DSL offers slightly lower latency by advantage of design.
Tradeoff is that DSL only uses one really shitty quality copper pair, that limits distance and maximum speed far more severely then cable's coaxial. This is exacerbated by the fact that many phone lines are from times before CAT3 home cabling, which is a realistic requirement to reach even ADSL2 level of speeds, causing end user speeds to be below 10mbps even over 24mbps ADSL2+ connection.
And yet no provider is going to stand for more than a couple of people actually operating at that speed more than a few hours a month. Lines are congested; transit isn't free. Internet access is being mis-sold just like everything else today: on the basis of a few upfront figures but ignoring the ongoing experience.
(Only yesterday I was confirming once again that there is no point upgrading my 10-year-old printer and CRT, while another dead mid-range LCD gets dismantled for parts after five years of life.)
This is the technology the Australian Coalition party is suggesting is equivalent/good enough compared to FTTH. If this is the first live deployment of it, I would want to know distances involved to get these speeds, and how many bonded pairs are required - and if these pairs are installed in Australian DOCSIS setups.
Also, no-one seems to feel that a symmetrical connection is valuable, focus is on download speed and upload speed a footnote. As a business operator with off-site backups, as well as transferring raw video content to be processed in other offices, upload speed is critical to me.
Latency yes... that was (is?) an issue... I recall from 10, 15 years ago when ADSL was no more than about 1 Mbit, cable would blast it away at about 5 Mbit. Down that is; up has always been a fraction of that only.
Me downloading stuff was happy about the speed compared to ADSL lines.
Gamers however complained cable is too slow - they care more about latency than raw throughput.
And indeed cable is a shared medium but I never really had a problem with that. May be luck.
I don't know about Harderwijk, but in the places where I've lived in NL there would be a tube from the house to the street, limiting the trenches to the actual street. There would be no trenches on your property.
Regardless, you're right. FTTH is (at this moment) unjustifiably expensive and disruptive when an alternative like this is available.
The test itself is important because cable operators are still, perhaps unfairly, seen by some as being inferior to fully fibre optic-based broadband services
Of course cable *is* (technologically) inferior to fiber. There's no doubt about it. 100Mbps would be trivial on fiber, heck 1Gbps would be trivial on fiber. The only advantage of cable is that it's already there, whereas for FTTH the vast majority of households will have to wait for a long time until they are connected.
I remember when cable TV came to my parents' home (roughly 25 years ago). Fantastic for me and my sister, more TV channels to watch! Anyway part of the installation was digging a trench to the house. I don't think they would ever use the existing pipes such as the sewage pipe.
It could be that this cable is in a tube by itself with room to get another cable through, I really wouldn't know.
Not all cable is a shared medium. Depends on the network. Some, like the old StjärnTV/Chello installations in Sweden, use a star topology rather than ring/loop.
Latency may once have been an issue. I ping to AMS-IX from Groningen (Netherlands) in less than 10 ms. Usually some 5-7 ms. I use a Ziggo connection (former @Home) and have never been so satisfied with performance. Only my previous ISP could match speed and latency. That was the university using ethernet and fiber connected to the educational backbone.
Cable DOCSIS 3 technology can achieve 160/100 mbps to a node, which is shared between 64, 128, or even more users, depending on how cheap/small the cable company is. For comparison's sake, Verizon's FIOS uses a Passive Optical Network (PON) to share 1 or 2.4 gbps among 32 users, depending on how aged the equipment is. Currently Verizon is testing XGPON, which will allow them to deliver 10 gbps to 32 users. This will make 1 gbps connections the standard. There is no competition between cable and fiber.
With high speed Internet, at one point it might be simpler to download zip with all relevant films ever made then to download it one by one. Lets assume there is 100 quality films created each year. For one movie in reasonable quality, you need 1GB. Assuming most people are interested in last 50 years of film industry and only few pieces older then that, you get something like 5TB zip file. Now, lets assume this 100Mbps line works on average with 60% avg. speed, it means 8 days to download "movie" file. So, still plenty room for improvement. We need something to download it overnight.
839*929
I think the fast speeds being offered now by the cable ISPs here is to proof to our government they don't need to invest in fiber networks and let the market take care of itself
What fast speeds. 10Mbit up is NOT enough... maybe for the coming 1 or 2 years but after that it's probably no longer enough.... and that 10Mbit up I only get when I take the most expensive subscription. I want a symmetric connection.
CAI Harderwijk is just a small provider with probably a relatively new network. UPC and Ziggo all have networks that are largely more than 20 years old with all the age problems included. Theoretically they will be able to do the same, practically not...
In the neighbourhood where I live, there will be fiber next year and I predict a marginalization for UPC in the coming years around here...They just won't be able to keep up...
In my opinion I can't see why consumers need higher speeds than this, I never reach the max speed because the sending end doesn't, exept using usenet.
Luckily not everyone is as shortsighted as you are...
And when using usenet my single SATA drive can hardly keep up.
Check your hardware, copying files from my home server goes with a speed that's at least 500 Mbit... Let me guess your internal network is only 100Mbit...
DSL proponents like to point out the shared nature of cable, but forget that all internet connections get shared at some point. Its just a question of the location where this first happens.
Cable users are, in practice, experiencing higher bandwidth than DSL users. The assumption from the DSL camp is that sharing closer to home is a downside for the end user, but the evidence seems to suggest otherwise..
Could it be that Cable networks are forced to structure themselves better due to their nature? That the immediate sharing is actually a downside for the provider (cost inefficiency) instead of the end user (service inefficiency?)
In short, doesnt DSL allow the provider to get away with using less equipment, and so they do, and you get less bandwidth because of it?
"His name was James Damore."
In the end we will end up with fiber, but not necessarily because of the obvious reasons. In Negroponte's book "Being Digital" he writes about the Chinese destroying the network because of theft of the copper. So the Chinese had to use fiber because copper based network became very expensive in numerous ways. I don't say the Dutch or citizens of any other country will steal the copper, but if there is so much speculation in the commodities prices might become so high fiber will become most attractive. I am Dutch. Just before the dot com boom I moved to a rented flat. This new flat had fiber everywhere and not yet cable. Then the dot com bubble exploded and neither the cabling, telephone or fiber company wanted to do further investments on their networks. I ended up living above a fiber network which wasn't finished and no cable, so I had to resort to my old 56K dailup modem, while most people had cable or adsl. I remember the price of downloading a debian iso image. My telephone cost where often around 800 euro's that time. Ofcourse I moved again shortly. But I still hear that on my old flat they don't have fiber, though they do have cable.
Comcast filters 100mbps cable speed news from its customers...
who prays for Satan? Who in 18 centuries has had the humanity to pray for the 1 sinner that needed it most? ~Mark Twain
Nope, CAI cable in the Netherlands is typically just the green cable in the ground with no further protection. On occasion they get torn up but by regulation they have to be put in at at least 80cm depth.
It is common when connecting new houses that the folks doing electricity, gas, cable and phone lines etc. time it so that all the stuff gets put into the ground at the same time though. Lot less hassle for everyone concerned, most of all the customer.
People replying to my sig annoy me. That's why I change it all the time.
The thing is with cable with 10 people on it, if 9 of them are downloading, fat chance of you checking your email.
With ADSL, the backhaul is more than likely far faster than the individual connections added together, so no speed degration for anyone.
Its all about where the bottleneck is, and 99% of cases its the bit closest to the users.
Why ? Can you not design a concentrator that shapes traffic intelligently, based on MAC addresses ? TCP will bring itself down usually.
Religion is what happens when nature strikes and groupthink goes wrong.
Having people think that they NEED FTTH is laughable at best. Really, take a moment and think of home many people you know that would actually utilize that pipe. Now think about how many people you know actually utilize all of a coax pipe even with a 10mbps xfer. 100mbps is pretty sweet, I can still remember upgrading my 14.4 modem to a 28.8. But if you think about it the only people that would actually use the full potential of that pipe are a few college kids sharing a place with all their xboxes hooked up while d/l the next crappy album by some band to put on their ipod.
That "Shitty quality copper pair" is Cat6 and feeds nearly every Major circuit in the country. Yes, if your how was built in the 50's it's possible that you have some really old copper, but most people have stuff that's relatively new. The problem with DSL AND cable modems is the willingness of ISPs to oversell the connection.
You seem to be assuming that there's no congestion control on the cable. In practice, if 9 people are downloading and you try to get your email then they will all be throttled back a tiny bit, won't notice, and you'll think your connection is fine. Most cable ISPs (outside the USA) resegment if a part of their network is being congested.
I am TheRaven on Soylent News
Keep pace with who? Another monopoly I am unware of? I'm pretty sure my ISP would deny the existence of DOCSIS 3 if I asked them about it, let alone this strange thing you call symmetry.
The thing is with cable with 10 people on it, if 9 of them are downloading, fat chance of you checking your email.
Got any citations for this?
You seem to think that if the provider offers 10Mbit, that thats all the cable line will carry, that 2 people downloading only get 5Mbit each..
Wrong.
"His name was James Damore."
The main difference between DSL and DOCSIS cable is that DSL is your personal connection. No one is sharing it. DOCSIS cable line is shared between those on the same line, so if you have active warez people in your neighbourhood or someone hosting an active server of some kind, expect much lower speeds and higher latency then advertised.
Second difference, which has been largely negated lately is latency. DSL offers slightly lower latency by advantage of design.
Tradeoff is that DSL only uses one really shitty quality copper pair, that limits distance and maximum speed far more severely then cable's coaxial. This is exacerbated by the fact that many phone lines are from times before CAT3 home cabling, which is a realistic requirement to reach even ADSL2 level of speeds, causing end user speeds to be below 10mbps even over 24mbps ADSL2+ connection.
This is VERY wrong.
#1. DSL is shared just like cable, just at a slightly different point. Several DSL customers connect to the same node and from there, they are given times slices. example. My brother has aDSL, he has ~20 people on his local node and he had an 80ms ping to his first hop. Yes, his ISP that is just down the road is an 80ms jump. If he had this dedicated connection you talked about, it would be impossible to have anything much more than 1ms to his ISP.
#2. even FTTH has local choke points. You don't connect directly to your ISP, you connect to a local node. Your local node is shared by many many people.
#3. Cable uses CDMA. You can have several people per channel talking at the same time. You share a local physical coax loop with a few of your immediate neighbors. This coax loop has a crap ton of bandwidth. You then connect from this coax loop to your local node, this node is shared by several loops.
The *only* difference between cable and other techs is that the connection between you and your node is shared, but your node to ISP is still fiber and has the same limitations of all the other techs.
My trace route to Chicago is about 700 miles long which is a 3ms ping at the speed of light in a vacuum. I get a 15-18ms pings to Chicago from my ISP , during peak hours I might add, and my ISP has over 2 million internet customers over that link.
**EVERY** consumer internet solution is shared bandwidth. That's the entire business model. The only question is which side of what router does everything get smashed together at. You used to hear DSL advertising that they weren't shared bandwidth, you don't anymore (at least in the US) because it's not true.
Wanted to add a few more things.
Obviously FTTH and FTTC is better than cable, but it's mostly better on the reduced noise on the line. DOCSIS tech is really good, but if there is something wrong with your coax, it can sometimes be hard to diagnose the issue. With fiber, there is much reduced chance of having intermittent issues and it's more likely to just not work. I would rather my connection completely fail so my ISP can fix it, than have a problem go away when my ISP shows up to fix the unknown problem.. gahh, i hate that
Most of cables bad rep comes from DOCSIS 1. v1 used time slices along with channels. This meant you may get good connection to your local node during off hours, but on peak hours you'd have to compete for time slices. Time slices suck horribly and scale badly.
DOCSIS 3.0 doesn't use time slices anymore and 2.0 it was optional. When using CDMA with 2.0/3.0, you get a pseduo-dedicated connection. Yes, your share the same line with your neighbors, *but* that don't allocate your bandwidth in any shape or form. When more people on the line does do is add noise. There will be an upper limit to the amount of people that can use a single line due to additional noise, but CDMA is quite resiliant.
An interesting note is that DOCSIS will scale to 1gbit on coax in future versions, it's already been announced.
recap.
#1. you get pseduo-dedicated bandwidth with CDMA enabled 2.0 and 3.0 docsis
#2. a 100gbit fiber connection to your ISP won't help at all if your ISP has too many customers and not enough bandwidth to the internet
#3. the different between fiber/cable/dsl is more an exercise of theory as a practical implementation from your ISP is the biggest issue.
#4. there are many choke points on any network, it just depends on your ISP to decide where yours is
#5. fiber rocks.
One of the things I hate about cable Internet is that, in the Netherlands (and probably elsewhere as well), consumers always seem to be given dynamic IP addresses. So, I called up CAI Harderwijk, a non-profit organization incidentally, to ask them directly about this. Apparently, they are indeed a cable operator (not an ISP), so they said this issue was always up to the various ISPs that make use of their infrastructure. Nevertheless, I asked why, in their opinion, do cable ISPs in general not offer fixed addresses? Well, they do, apparently, since this is also possible with previous DOCSIS versions, but its a privilege that is usually reserved for business customers. Most cable ISPs consider it unnecessarily expensive to provide all customers with fixed IP addresses.
Otherwise, CAI Harderwijk now have a thoroughly modern infrastructure. For instance, they can remotely control the availability of their services to individual clients. This is as opposed to UPC (the only available cable ISP in and around Amsterdam), who still have to arrange their client connections locally and manually. The latter method has the added disadvantage that a small percentage of cable customers will always enjoy services for which they do not pay -- something that is impossible to avoid due to the scale and the administration involved. CAI Harderwijk does not have this problem; an advantage that they can now pass on to their ISP customers.
It is true, that fiber has more theoretical bandwidth. Light operates up in the 100s of THz range. However making use of all that potential bandwidth isn't as easy as one might hope, particularly in a passive network. Remember that FTTH is NOT fiber like you find in a data center. It is not a point-to-point, active network. It is a passive optical network. That is a point-to-multipoint setup where you have multiple people connected using passive optical splitters and you are sharing bandwidth.
Well this implies a whole bunch of things. One is like I said bandwidth sharing with others (as happens with cable), another is that while WDM is used, it is only used to put downstream, upstream and video on one fiber. There aren't multiple channels for DS and US at this point. Also the technology for the signaling isn't as fast as you might hope. While gigabit stuff is coming online in some places and 10G is in development, most of it is BPON which is OC-3 to OC-12 speeds (155-622mb). Not bad at all, but not as fast as you might think, and not outside of what DOCSIS 3 can do. Currently at my place I'm on a network with a total of 152mb/sec of potential bandwidth with the number of channels in use (4) and more can be added.
Don't get me wrong, fiber has more bandwidth potential and there's no question on that. However cable is not as bad as you think, nor is the fiber technology you get to your house as advanced as you might wish.
Cable still holds its own quite well, especially when you compare speeds to what is useful. While geeks love to gush over bandwidth numbers for their own sake, you have to ask how much really matters. How much really makes a difference in a browsing experience for a normal user, on the net right now. Well that depends on how fast servers will hand things out, what kind of bandwidth things like video need, and so on. Well turns you that 20mbit is pretty much "good enough for anyone." Around there you stop noticing much improvement with higher speeds. Sites just won't send you the data much faster, it is enough to stream even very high quality HD video, there just isn't much improvement at present moving to something faster.
I've gone from 20mbit to 50mbit (and actually more like 100mbit in reality because they are not choosing to limit my modem at this time) and the improvement is extremely minor. Browsing the web is no different (nor is it any different at work on a gig network out to a good deal of bandwidth), I wait on ad serving sites to respond or the browser to render, if anything. It is instant in most cases. Files don't really download any faster form most places, they just won't give a single user more bandwidth. Steam does get faster downloads, if their servers aren't loaded, but that's about all. Any video streams immediately and well, including the high bandwidth HD stuff form places like VUDU. I like my faster net, because it is cool, but in terms of user experience it really is a wash.
Fiber is the ultimate way to go, but there is no need to rush on it. Cable really does have a lot of life left to it.
>>>I recall from 10, 15 years ago when ADSL was no more than about 1 Mbit,
Yeah well ADSL is now 100 Mbit/s with a just-released 200 Mbit/s standard being rolled out. Unfortunately you have to live in Korea or Japan to get it. :-| Still the technology exists to enable DSL to match Cable speeds, and it's a dedicated phone line not a shared neighborhood coax cable, so the user gets what is advertised.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
This is VERY wrong.
#1. DSL is shared just like cable, just at a slightly different point. Several DSL customers connect to the same node and from there, they are given times slices.
It's unclear what you call a 'node'. If you mean a local exchange then yes obviously a lot of people are going to connect to it. However each ISP usually has their own DSLAMs there and the customer's line plugs directly into the ISPs DSLAM. Then upstream of the DSLAM of course every thing travels on a single 'cable'. However that is normally a fiber optic line with far more bandwidth than the DSL lines that connect to it so it's no issue. There are still cases where the DSL plugs into a competitor's DSLAM and where the traffic is then transmitted to your ISP, at cost to the ISP, via fiber optic lines. However, at least in France, that's less than something like 10% of the lines and is being eliminated as fast as possible (remember the 'at cost' part).
example. My brother has aDSL, he has ~20 people on his local node and he had an 80ms ping to his first hop. Yes, his ISP that is just down the road is an 80ms jump. If he had this dedicated connection you talked about, it would be impossible to have anything much more than 1ms to his ISP.
The extra latency you see is mostly created by the DSL error correction algorithms. Some ISPs (e.g. Free in France) let you choose the level of error correction on your DSL line which lets you adjust the tradeoffs between bandwidth, latency and packet loss.
The *only* difference between cable and other techs is that the connection between you and your node is shared, but your node to ISP is still fiber and has the same limitations of all the other techs.
That's a significant difference. With cable the choke point is where it is hardest to fix: the last mile. With fiber the choke point is where it is trivial to fix: between the local exchange and the rest of the Internet.
Case in point: some poster mentioned 'still' getting 5-6Mbps during peak hours out of 50Mbps theoretical. I have ADSL and I still get 12Mbps during peak hours which is the maximum my line supports given its length. So either his ISP really skimped on upstream bandwidth, or more likely his choke point is still in the last mile cable connection.
Cable is basically always star with regards to multiple houses. Reason is that cable companies need to be able to charge per house, connect and disconnect services per house. If it was looped through all places, well then they'd lose any ability to do that.
What you also discover is that for a lot of reasons, cable Internet being one of them, they've built out the fiber part of their network quite far. The cable network isn't all coax and hasn't been forever. It is called a HFC, Hybrid Fiber Coax, network because that is what it is. So you find that because of that, they can and do segment it down pretty far. Yes you'll share with other places, but probably somewhere in the 32-128 realm, which is the same you get with a FTTH PON connection.
Also with DOCSIS 3 they can separate users out even more. DOCSIS 3 allows for multiple channels to be used for data (that is how it gets its speed). Well they can have even more channels than a single person gets. So each user gets, say, 4 channels (152mbits) on their modem. However they have a total of 16 channels for a segment. They then stagger what channels users are on so there's less sharing going on.
Don't get me wrong, FTTH has the capacity to be faster in the long run, fiber optics just has more theoretical bandwidth because of that whole Shannon's Law thing. However cable can work very well, and does when providers want it to.
I shouldn't have started my rebuttal with "This is VERY wrong".
I'm sorry.. :*(
I should've stated something more like "DSL being "dedicated" is a common misconception" or something.
Wrong, because even DOCSIS 2.0 supports 38 megabits/second. However, users are NEVER sold this full amount. They're sold a much lower cap.
For example, my Time Warner service is capped at 5 megabits/second. (The modem itself enforces this cap, probably modern headends double-check to make sure the modem has not been tampered with.) So it takes nearly 8 simultaneous full-downstream users before anyone sees evidence that their line is shared. For upstream, I have a cap of 512 kbps if I recall correctly. This means it'll take approximately 50 users saturating their upstream before I see any evidence of sharing of the 27 megabits/sec upstream channel.
The cable providers can pretty easily throw extra channels at the problem, splitting the load even more.
However, where the cable providers have underspent on infrastructure is their backhaul (e.g. their connection to the Internet). At this point they have the same problems as DSL users.
retrorocket.o not found, launch anyway?
Well, at 100Mbps you're using enough channels that it's unlikely that there are more channels open on the local segment for data unless the cable operator has moved to exclusively using switched digital video.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Good job exploding the DSL vs cable myth. The tired old mantra is just repeated mindlessly as if the repeater understood a single thing about the issues involved. Everything depends on the particulars of each case.
>>>DSL proponents like to point out the shared nature of cable, but forget that all internet connections get shared at some point
If the DSLAM is being fed with a 10 Gbit/s fiber line, then no, there won't be any slowdown even if all your DSL neighbors decide to bittorrent at the same time. A coaxial cable can carry about 5 Gbit/s... minus about 2400 Mbit/s for television and on-demand channels... leaving just ~2.5 Gbit/s for your neighborhood. i.e. Less bandwidth.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
Cat6 has NEVER been used for POTS line in the US, those are all going to be CAT3, and further even if they *were* Cat6 that wouldn't get you 100Mbps past a couple hundred meters, the only way to achieve those kinds of speeds is to do fiber to the curb or at most a remote shelf very near the house.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
It's fairly obvious that ANY internet connection is shared at some point. Hell, one of the main attractive points of using IP was how well it performed on shared connections.
Point was that, the point where you share your connection with other people on DSL is on DSLAM, which can both QoS people who such too much, as well as being connected with far more bandwith then last mile, typically making it impossible to congest by a single, or even several users. Essentially your copper pair going from DSLAM to your house is YOURS. No one is sharing it.
With cable, your last mile is shared, which means that your only means of not letting one or several users raping the line is to QoS the last mile, by slowing people down. The cable opening at your house is SHARED with other people.
This is a VERY significant difference. Obviously, as someone else already pointed out, there are places that use star topology for cable. Those are extremely rare however, because the amount of bandwith wasted is pretty epic in proportions to standard circle.
Now you can try to kill the point by pointing out the pointless "but it's shared on another level!". But you'll be missing the main point on purpose just to split hairs.
Er, we also need medical services. It is arguable that society should provide food, water, shelter, and medical services at some level to everyone at no direct cost[*]. If it doesn't do that, it is questionable what the value of society is in moral terms. I don't think there has ever been a governmental jurisdiction in the world which has done this, however. I guess the best is yet to come :)
[*] Yes, tiresome libertarian extremists, I am aware that nothing is without cost. I am talking about point of provision charges.
Let me just chip in. I'm a Freenaute too, but i moved from Poland having a UPC (docsis 2, then docsis3) connection. The difference is astounding. Using ADSL2+, the top i can get is 28MB/s, but realistically nobody gets more than 12MB/s (on average) because of the distance to the DSLAM, which tends to be 1km-2kms. I get 10. Is there a way to fix that? No, because Cat3 can't carry frequencies above 2Mhz at that distance.
For comparison, i get 50MB/s back in PL without the line ever breaking a sweat, and if i wanted to i can upgrade to 100MB/s (i haven't since i don't have a router *at home* that can handle the traffic) on a whim. And why? Because with a copper shielded cable the cable doesn't experience interference, and the width of *one channel* is more the total bandwith of one ADSL line.
I really get that for an ISP, Free is trying really hard to make ADSL suck less (by not using PPP for example, all the extras), but from personal experience Docsis > ADSL any time.
DOCSIS 2.0 supports 30Mb/s upstream PER CHANNEL, and either 42 or 55Mb/s downstream PER CHANNEL. The channels aren't shared between users that I know of.
For example, my Comcast is capped at 16Mb/s (my choice, they also offer 25, 30 and 50Mb service), and my upstream will peak at 30Mb/s in short bursts (First 10MB or so) then settle back to 10Mb/s. A year ago I had completely uncapped service and was able to download at the full 42Mb/s rate (although I could swear it was 52-55Mb/s), and I saturated the line for a week with no issues, no slowdowns, and my neighbors were completely unaffected.
You totally missed the GP's point (although he didn't state it very clearly.)
With most DSL setups, if you do a tcpdump on the interface connected to your DSL modem, you only see your machine's traffic. With DOCSIS setups, you see all the traffic from your neighbors' machines, as well.
I think everyone here realizes that at some point upstream your traffic is aggregated with your neighbors' traffic.
DSL is a bit different because of the dslam, but Fiber and Cable is nearly the same.
Fiber lines have a dedicated line to the local node, the local node is shared by others and connects to the ISP via fiber. Cable has as shared connection to the node, but the node is connected to the ISP via a fiber link also.
Case in point: Some posters in other forums for my cable ISP claim that they get their 60mbps during peak hours and their power boost even hits ~120mbps.
The issue isn't too many customers on the same COAX, but too many customers on the same node. If a Node has a 1gb fiber link and you have 100 customers, each with a 60mb connection, you're node is going to be overwhelmed. If you think changing the connection between the user and the node is going to make the connection from the node to ISP faster, I'd like to take what you're taking.
"today you have your own dedicated frequencies until the central hub in your area (AKA your personal connection). just like with ADSL."
That is entirely false. Layer 2 in a DOCSIS plant is shared fully amongst every cable modem locked on a given channel. Downstream access is scheduled by the CMTS entirely, while upstream access is requested by cable modems, and scheduled by the CMTS.
Additionally, the idea that shielded conductors somehow make distance trivial is absurd. DOCSIS cable plants are HFC, with fiber pushed as far out as possible. So far out, in fact, that many DOCSIS operators see PON as a natural evolution in their last mile. This isn't done just because fiber is super cool, or because yellow looks better than black. It's done because as soon as you transition to copper, the signal quality goes to absolute crap. In the main neighborhood copper loop after the last fiber node in an HFC plant, you lose as much signal intensity over a dozen feet as you do in a mile of off-the-shelf single mode optical fiber.
Fiber can be slow if they overload a node to. The issue isn't the connection from the customer to the node, but from the node to the ISP.
Since the difference between fiber and cable is customer to the node and that isn't the issue, then there is no major difference with current sub 1gb speeds.
Put 100 customers with 60mbit on a node with a 1gbit connection and ANY tech is going to have bandwidth issues.
I would still rather have fiber just because there are fewer "random" issues and issues are easier to fix, but cable works just fine if the ISP implements it correctly.
There are other forums on the internet that I watch for info about my ISP so I can stay on top of their offerings and upgrades. MANY customers claim that their 60mbit connections get 60mbit at peak hours and even burst up to 120mbit using power boost.
My ISP isn't magical in anyway, they just don't overload their nodes.
In the past year, my worst ping to Chicago has been 22ms. During off peak, I get 15ms and peak is closer to 19ms. I get 0-2ms jitter on average, 2ms jitter during peak.
I have always gotten my 16mbit speed. During peak hours, I may have to download from multiple sources to reach 16mbit, but that's not my ISP, that's the web site. I can maintain 16mbit down while playing FPS games with an in-game 20ms ping.
I really want the 60mbit package, but going from $40/month to $99/month is a bit out of my price range. The 25mbit is $55 though.. eyeing that up.
I may be an exception, but that's not an exception in technology, I'm an exception in how my ISP doesn't overload their nodes.
Again, cable isn't inherently much worse. If you have a good cable, with no nicks and no bad physical connectors, cable should be the same as fiber. Where they differ is fiber is easier to have a good line and easier to diagnose if the came is bad.
Channels are shared between users - 1.0/1.1 used TDMA, 2.0/3.0 use either TDMA or S-CDMA.
However, as I mentioned in my post, as user count goes up, providers can throw more channels at the problem.
e.g. if you wanted to give 5 Mbps without any potential for slowdown within the cable network (not counting overselling of your backhaul), you could assign 7 users per channel. 8 users per channel would have a slight bit of sharing, but negligible.
DOCSIS 3.0 supports bonding of multiple channels.
My guess is that as you increase your caps towards the maximum capability of DOCSIS 2.0, you are more and more likely to see sharing effects. However, you're even more likely to see evidence of the backhaul being oversold long before that with most cable providers.
retrorocket.o not found, launch anyway?
That's absurd. The entire distinction between DOCSIS and FTTH is in the last mile, because they're last mile technologies. You can't just pass the last mile distinctions off as being trivial, when they're the only distinctions to be made. 56k modems on DS0s have dedicated lines to the CO, and that CO likely does optical transport deeper into the network. Does that make them "nearly the same" as DOCSIS and FTTH as well?
The thing is with cable with 10 people on it, if 9 of them are downloading, fat chance of you checking your email. With ADSL, the backhaul is more than likely far faster than the individual connections added together, so no speed degration for anyone.
DOCSIS 3.0 is very different from ethernet - most importantly it's strictly time multiplexed. And slice allocation is such that you will be able to read your email just fine while your neighbors download and/or upload. There is no collision domain. So while it's "shared" it's not a free-for-all where the one with the most TCP connections wins. Fire up more connections and they just compete for your existing allocation. You're the only one who won't be able to check your email.
The same basic metric applies: the degree to which POP capacity is oversold. DSL is always oversold, and no the link from the CO/POP is not infinite, in fact an entire suburban neighborhood might be on a single 22M link. The main difference is that cable has a whole lot more bandwidth to go around and is less oversold. It also does traffic shaping closer to the customer.
That is not entirely true, you have a personal cable, but the DSLAM unit in the telephone operators building is shared mostly with 100/50/20/10 other subscribers, only the most expensive business DSL subscriptions come with a 1:1 congestion.
Each channel individually can do up to 42.66 Mbps downstream (U.S. DOCSIS) all on its own. It isnt hard to imagine ALL provider having at least 12 free channels, which equates to 512Mbps of downstream capacity.
This is why its hard to believe the grandparents claim that 9 users downloading at the same time can prevent you from getting your email.
"His name was James Damore."
My thought was 9 users x2 channels (full speed downloads) = 18 channels plus a few for uploads which is AFAIK more than most providers will have set aside for data unless they have moved to SDV.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
If the DSLAM is being fed with a 10 Gbit/s fiber line, then no, there won't be any slowdown even if all your DSL neighbors decide to bittorrent at the same time.
You begin with an If.... and then limit the equation to only your neighbors.... and only want to follow the link back to the DSLAM, ignoring the BRAS that many DSLAMS converge on.
To put this as succinctly as possible. The BRAS needs to be able to handle every user of every DSLAM it connects to. We are talking about massive areas of coverage all going to a single point.
Evidence of the problem is that DSL users complain about prime time bandwidth just as much as Cable users. It doesnt mean anything that the bottleneck isnt the DSLAM, which is all you have talked about.
"His name was James Damore."
For TV I prefer my satellite dish and we are waiting for legislation to force the cable owners to allow other ISP's access.
The cable ISP's are notorious for their lack of service and totally clueless help desks, until they match good ol' xs4all.nl I'm not tempted and stay on VDSL with 40/3Mbits/sec and especially shell access.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
"laying FTTH" of course is nice, but it's also mighty expensive and disruptive to break open all the streets and dig trenches to everyone's home.
Most recent developments already have underground conduits. It shouldn't require more than targeted digging where each individual feed branches from the main. Not cheap, but I would think it's better than tearing up a whole street.
Most older developments have phone poles. They're not ideal, but it's doable to run fiber along them, and less expensive than digging to boot.
At the very least we should mandate that fiber runs be included in the infrastructure of any new developments, if that isn't already the case. I know my home was built just over a decade ago during the dot com era, and some homes down the road were build less than three years ago, but none of us have fiber... maybe things have changed since then.
https://www.eff.org/https-everywhere
Interesting.
(1) I've never experienced any kind of slowdown on my DSL line, whereas I have seen it on my neighbors' cable lines. My DSL runs at peak speed all the time.
(2) "bras" is a most excellent name. ;-)
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
I see. We are probably just very lucky out here then that Comcast isn't overselling their local capacity by enough to affect us.
BTW, I do believe that I swapped out my modem for a DOCSIS 3.0 one not too long ago as I think they said that was required for a 50Mb/s connect. I just didn't have to swap it back to the older modem when I downgraded back to 16Mb/s.
Currently where I am, they consider 16Mb/s down, 5Mb/s up as the entry level. Noone has lower than that. All older connections got bumped up to that as it became available, with options for 20,25,30, 50Mb and supposidly 100Mbs as well.
No, I mentioned 5-6 MB/s out of a 50Mb/s theoretical max.... B=Byte, b=bit....
Geez, and this is a geek site...
Most older developments have phone poles. They're not ideal, but it's doable to run fiber along them, and less expensive than digging to boot.
Many places outside of the USA (like The Netherlands what this story is about) keep all their cables underground, except high voltage power lines. Actually all of Europe does this, except in the mountains where the ground is too rocky to dig. It costs more to set up, but much more reliable and no ugly poles all over the place.
The issue isn't too many customers on the same COAX, but too many customers on the same node. If a Node has a 1gb fiber link and you have 100 customers, each with a 60mb connection, you're node is going to be overwhelmed. If you think changing the connection between the user and the node is going to make the connection from the node to ISP faster, I'd like to take what you're taking.
That really reminds me of all the discussions saying DSL was useless because already with 0.056Mbps modems the bottleneck was the connection between the local exchange and the ISP. Yet here I am maxing out my 12Mbps (>200x faster) ADSL connection anytime I want. I guess they must have upgraded the connection between the local exchange and the rest of the network. Why you think they will never do that again is beyond me.
No, I mentioned 5-6 MB/s out of a 50Mb/s theoretical max.... B=Byte, b=bit....
Geez, and this is a geek site...
Oh sure use inconsistent units and then blame it on others when they miss a case difference.
so the user gets what is advertised.
ROFLMAO
Firstly the advertised speed for DSL is generally the speed on a "perfect" line. Unless you have a FTTP setup or similar scenario where all copper lines are very short speeds are often much lower than advertised.
Secondly while there may not be contention on the local loop there is almost certain to be contention somewhere either in the ADSL backend network or in the network that joins it to the internet.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Each channel individually can do up to 42.66 Mbps downstream (U.S. DOCSIS) all on its own. It isnt hard to imagine ALL provider having at least 12 free channels, which equates to 512Mbps of downstream capacity.
This is why its hard to believe the grandparents claim that 9 users downloading at the same time can prevent you from getting your email.
Adding to that is CDMA. A CMDA phone can handle hundreds to thousands of users on the same channel at the same time.
Now, cable doesn't have all the interference from air. In my case, about 20-30 users on my node. 8-12 channels, each at ~42mbps each. Toss in CDMA and you can easily have several gigabits of bandwidth.
I'm not going to have an major benefit using fiber until my ISP starts offering 200mb+ connections. Even then, DOCSIS 4.0 will come out which promises 1gb of bandwidth per user, assuming your cable operator doesn't over subscribe and your node/ISP can handle it.
I would LOVE un-capped bandwidth for local connections though.
I would *prefer* fiber, but going to fiber will give me no extra bandwidth or noticeably reduced latency.