How fast is Internet traffic growing?

It depends on whose numbers you like. Andrew Odlyzko claims it’s up 50-60% over last year, a slower rate of growth than we’ve seen in recent years. Odlyzko’s method is flawed, however, as he only looks at public data, and there is good reason to believed that more and more traffic is moving off the public Internet and its public exchange points to private peering centers. Nemertes collects at least some data on private exchanges and claims a growth rate somewhere between 50-100%.

The rate of growth matters to the ongoing debates about Internet regulation. If Odlyzko is right, the rate of growth is lower than the rate at which Moore’s Law makes digital parts faster and cheaper, so no problem, routine replacement of equipment will keep up with demand (leaving out the analog costs that aren’t reduced by Moore’s Law.) If Nemertes is right, user demand outstrips Moore’s Law and additional investment is needed in network infrastructure. Increased investment needs to be covered by government subsidies or by the extraction of additional value from the networks by their owner/operators. Subsidy isn’t going to happen while the economy teeters on the edge of collapse, so the high growth conclusion argues against regulations designed to preserve the legacy service model. It’s a vital question.

A couple of new data points emerged this week. Switch and Data, operator of PAIX public exchange points in Palo Alto and New York, says its traffic grew 112% last year:

International networks are making the decision to peer in the United States to reduce transit time between countries and accelerate the performance of U.S. and other global websites in their home markets. This is important due to the explosive growth of Web 2.0 with its bandwidth intensive websites for social networking, rich digital content, and business software applications. Exchanging traffic directly between content and end user networks also significantly reduces Internet transit expense which has been a rapidly growing cost for companies as their traffic volumes soar.

At the Switch and Data New York peering center, traffic was up an astonishing 295%.

Combining these numbers with what we know about the Content Delivery Networks that deliver as much as half of the Internet’s traffic, I think we can reasonably conclude that comprehensive measurement of Internet traffic would support the theory that traffic still grows at an increasing rate. One side effect of the increased use of CDNs and private peering is less certainty about the overall state of Internet traffic. Studies confined to public data are less and less useful, as many researchers have been saying for years.

At any rate, there’s considerable uncertainty about this question at the moment, which argues that the Internet needs a Nate Silver to pierce the fog of conflicting polls.

Cross-posted at CircleID.

4 thoughts on “How fast is Internet traffic growing?”

  1. What do you think of Kenjiro Cho’s study in Japan? His study has been done at 6 of the major ISP’s in Japan every year for multiple years. It doesn’t show the increase in traffic growth that you reference.

  2. Do you have a citation to something in the last two years? All of Cho’s published work that I’ve seen doesn’t cover the period under discussion and is colored by the fact that Japan has had FTTH longer and more extensively than we have in the US.

    He does say this: “From this result, it would be misleading to simply rely on data from IXes to estimate and understand nation-wide traffic, because a considerable amount of traffic is exchanged by private peering.” – The Impact and Implications of the Growth in Residential User-to-User Traffic, Cho et. al., SIGCOMM’06, September 11–15, 2006, Pisa, Italy.

    That’s a direct indictment of Odlyzko’s method.

  3. Whatever methodologies these folks are using, they very likely don’t have the sort of immediate results that we get from our direct experience as an ISP. We saw a 30% growth in bandwidth demand in the past quarter as more and more users began to consume online video. (P2P usage has grown for other providers, but hardly at all for us because we prohibit it on residential connections.) Worse still, we’ve customers threaten to leave if their online video was not perfectly smooth and free of halts and stops — yet they were unwilling to pay more for the additional bandwidth that was consumed when multiple members of their household attempted to stream those videos at once. ISPs were squeezed before; we’re really geting hammered now.

  4. We have a new paper on Japanese residential traffic to appear in ACM
    CoNEXT2008.

    Kenjiro Cho, Kensuke Fukuda, Hiroshi Esaki and Akira Kato.
    Observing Slow Crustal Movement in Residential User Traffic.
    To appear in ACM CoNEXT2008. Madrid, Spain. December 2008.

    http://www.iijlab.net/~kjc/papers/kjc-conext2008.pdf

    abstract:
    It is often argued that rapidly increasing video content along with
    the penetration of high-speed access is leading to explosive growth
    in the Internet traffic. Contrary to this popular claim, technically
    solid reports show only modest traffic growth worldwide. This paper
    sheds light on the causes of the apparently slow growth trends by
    analyzing commercial residential traffic in Japan where the fiber
    access rate is much higher than other countries. We first report that
    Japanese residential traffic also has modest growth rates using
    aggregated measurements from six ISPs. Then, we investigate
    residential per-customer traffic in one ISP by comparing traffic in
    2005 and 2008, before and after the advent of YouTube and other
    similar services. Although at first glance a small segment of
    peer-to-peer users still dictate the overall volume, they are slightly
    decreasing in population and volume share. Meanwhile, the rest of the
    users are steadily moving towards rich media content with increased
    diversity. Surely, a huge amount of online data and abundant headroom
    in access capacity can conceivably lead to a massive traffic growth at
    some point in the future. The observed trends, however, suggest that
    video content is unlikely to disastrously overflow the Internet, at
    least not anytime soon.

    -Kenjiro

Leave a Reply

Your email address will not be published. Required fields are marked *