Quote:
Originally Posted by Horizon
Would it be accurate to say that 16 channels or 800mb is the maximum download capacity available in any one area? And potentially using the most extreme example, that 800mb has to serve the following:
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Depends on the area, not all areas have 16 channels, some may have more, some may have less. They stared with as low as 3 per area and have been adding more as and when required. AFAIK most should have at least 8 by now but that's not necessarily the case.
There's no hard limit that says they cannot deliver more than 16 channels through one node either.
Should also point out your extreme example is indeed an extreme example, uptake, population density, node size, and cabinet size all vary widely, one cabinet does not always equal one node, and finally, 3.6Mb per customer isn't actually all that bad.
Not long ago ISPs were selling to a contention ratio of about 50:1, meaning a "Up to 24Mbps" ADSL customer could be allocated only 0.5Mbps (or less). I recall once hearing of a certain ISP only allocating sufficient bandwidth for 64Kbps per customer at peak time. Consumer ISPs have always been overselling to those sorts of levels, on the basis that most people will not be using most their speed most of the time. That's how consumer broadband ended up being so cheap.
---------- Post added at 18:57 ---------- Previous post was at 18:48 ----------
Quote:
Originally Posted by MaverickJesus
Out of interest, what do you see as a 'sensible' configuration? Keeping in mind reasonable financial constraints, of course.
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IMO 50:1 contention ratios are just fine, especially on faster lines. Back where I used to work, we had around 2,200 student residences sharing 1000Mbps of capacity. And that never went above 30% load. Course, that was 2006...
Last I recall the average consumer used something around 50GB a month or less. On an average connection speed of 12Mbps, that's about 1.2% the capacity of their line. Assuming usage was evenly distributed throughout the month (which it isn't) then you'd only need 144 kbps per customer for everyone to get full speed. Even on VM where average speeds are over double that, 3.6Mbps is still over ten times the bare minimum in worst case scenario, supposedly. Which really isn't that bad.