Network end users to pull down 2 gigabytes a day, continuously?
tme at multicasttech.com
Mon Jan 8 12:03:46 UTC 2007
On Jan 8, 2007, at 2:34 AM, Sean Donelan wrote:
> On Sun, 7 Jan 2007, Joe Abley wrote:
>> 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.
> As long as the additional traffic doesn't exceed the existing
> But what happens when 5% of the paying subscribers use 95% of the
> existing capacity, and then the other 95% of the subscribers
> complain about poor performance? What is the real cost to the ISP
> needing to upgrade the
> network to handle the additional traffic being generated by 5% of the
> subscribers when there isn't "spare" capacity?
>> 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.)
> The reason why many universities buy rate-shaping devices is dorm
> users don't restrain their application usage to only off-peak
> hours, which may or may not be related to sleeping hours. If peer-
> to-peer applications restrained their network usage during periods
> of peak network usage so it didn't result in complaints from other
> users, it would probably have a better reputation.
Do not count on demand being geographically localized or limited to
certain times of day. The audience for streaming is world-wide (for
an example, see
for a few hour slice in the early evening EST on a Sunday - note,
BTW, that this is for English language content). The roughly equal
distribution to the US and the EU is entirely normal; typically the
peak-to-trough bandwidth usage variation during a day is less than a
factor of 2, and frequently it disappears all together.
>> 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.
> Depends on when and where the replication of the content is taking
> Broadcasting is a very efficient way to distribute the same content
> to large numbers of people, even when some people may watch it
> later. You can broadcast either streaming or file downloads. You
> can also unicast either streaming or file downloads. Unicast tends
> to be less efficient to distribute the same content to large
> numbers of people. Then there is lots of events in the middle.
> Some content is only of interest to a some people.
> Streaming vs download and broadcast vs unicast. There are lots of
> combinations. One way is not necessarily the best way for every
> situation. Sometimes store-and-forward e-mail is useful, other times
> instant messenger communications is useful. Things may change over
> time. For example, USENET has mostly stopped being a widely
> flooded through every ISP and large institution, and is now
> accessed on demand by users from a few large aggregators.
> Distribution methods aren't mutually exclusive.
>> 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.
> If you limit yourself to the Internet, you exclude a lot of content
> being shifted around and consumed in the world. The World Cup or
> Superbowl are still much bigger events than Internet-only events.
> television shows with even bottom ratings are still more popular
> than most Internet content. The Internet is good for
> narrowcasting, but its
> still working on mass audience events.
> "Asynchronous receivers" are more expensive and usually more
> than "synchronous receivers." Not everyone owns a computer or
> spends a
> several hundred dollars for a DVR. If you already own a computer,
> you might consider it "free." But how many people want to buy a
> computer for each television set? In the USA, Congress debated
> whether it should
> spend $40 per digital receiver so people wouldn't lose their over
> the air broadcasting.
> Gadgets that interest 5% of the population versus reaching 95% of
> the population may have different trade-offs.
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