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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."
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 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.
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.