Network end users to pull down 2 gigabytes a day, continuously?

Joe Abley jabley at
Sun Jan 7 20:07:45 UTC 2007

On 7-Jan-2007, at 15:17, Brandon Butterworth wrote:

>> The only time that costs increase is when I download
>> data from outside of BT's network because the increased
>> traffic reaquires larger circuits or more circuits, etc.
> Incorrect, DSLAM backhaul costs regardless of where the traffic
> comes from. ISPs pay for that, it costs more than transit

Setting aside the issue of what particular ISPs today have to pay,  
the real cost of sending data, best-effort over an existing network  
which has spare capacity and which is already supported and managed  
is surely zero.

If I acquire content while I'm sleeping, during a low dip in my ISP's  
usage profile, the chances good that are nobody incurs more costs  
that month than if I had decided not to acquire it. (For example, you  
might imagine an RSS feed with BitTorrent enclosures, which requires  
no human presence to trigger the downloads.)

If I acquire content the same time as many other people, since what  
I'm watching is some coordinated, streaming event, then it seems far  
more likely that the popularity of the content will lead to network  
congestion, or push up a peak on an interface somewhere which will  
lead to a requirement for a circuit upgrade, or affect a 95%ile  
transit cost, or something.

If asynchronous delivery of content is as free as I think it is, and  
synchronous delivery of content is as expensive as I suspect it might  
be, it follows that there ought to be more of the former than the  
latter going on.

If it turned out that there was several orders of magnitude more  
content being shifted around the Internet in a "download when you are  
able; watch later" fashion than there is content being streamed to  
viewers in real-time I would be thoroughly unsurprised.


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