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Archives for 2007

Comcast and Net Neutrality

October 24, 2007 by

The revelation that Comcast is degrading BitTorrent traffic has spawned many blog posts on how the Comcast incident bolsters the blogger’s position on net neutrality – whatever that position happens to be. Here is my contribution to the genre. Mine is different from all the others because … um … well … because my position on net neutrality is correct, that’s why.

Let’s start by looking at Comcast’s incentives. Besides being an ISP, Comcast is in the cable TV business. BitTorrent is an efficient way to deliver video content to large numbers of consumers – which makes BitTorrent a natural competitor to cable TV. BitTorrent isn’t a major rival yet, but it might plausibly develop into one. Which means that Comcast has an incentive to degrade BitTorrent’s performance and reliability, even when BitTorrent isn’t in any way straining Comcast’s network.

So why is Comcast degrading BitTorrent? Comcast won’t say. They won’t even admit what they’re doing, let alone offer a rationale for it, so we’re left to speculate. The technical details of Comcast’s blocking are only partially understood, but what we do know seems hard to square with claims that Comcast is using the most effective means to optimize some resource in their network.

Now pretend that you’re the net neutrality czar, with authority to punish ISPs for harmful interference with neutrality, and you have to decide whether to punish Comcast. You’re suspicious of Comcast, because you can see their incentive to bolster their cable-TV monopoly power, and because their actions don’t look like a good match for the legitimate network management goals that they claim motivate their behavior. But networks are complicated, and there are many things you don’t know about what’s happening inside Comcast’s network, so you can’t be sure they’re just trying to undermine BitTorrent. And of course it’s possible that they have mixed motives, needing to manage their network but choosing a method that had the extra bonus feature of hurting BitTorrent. You can ask them to justify their actions, but you can expect to get a lawyerly, self-serving answer, and to expend great effort separating truth from spin in that answer.

Are you confident that you, as net neutrality czar, would make the right decision? Are you confident that your successor as net neutrality czar, who would be chosen by the usual political process, would also make the right decision?

Even without a regulatory czar, wheels are turning to punish Comcast for what they’ve done. Customers are unhappy and are putting pressure on Comcast. If they deceived their customers, they’ll face lawsuits. We don’t know yet how things will come out, but it seems likely Comcast will regret their actions, and especially their lack of transparency.

All of which – surprise surprise – confirms my position on net neutrality: there is a risk of harmful behavior by ISPs, but writing and enforcing neutrality regulation is harder than it looks, and non-regulatory forces may constrain ISPs enough.

Filed Under: Broadband Tagged With: , ,

Comcast Blocks Some Traffic, Won't Explain Itself

October 23, 2007 by

Comcast’s apparent policy of blocking some BitTorrent traffic, which has been discussed on tech sites [example] for months, has now broken out into the mainstream press. Comcast is making things worse by refusing to talk plainly about what they are doing and why. (This is an improvement over Comcast’s previously reported denials, which now appear to be inconsistent with the facts.)

To the extent that Comcast has explained itself, its story seems to be that it is slowing traffic from heavy users in order to keep the network moving smoothly. This would be a reasonable thing for Comcast to do (if they were open about it) – but it’s not quite what they’re actually doing.

For starters, Comcast’s measures are not aimed at heavy users but rather at users of certain protocols such as BitTorrent. And not even all users of BitTorrent are targeted, but only those who use BitTorrent in a particular way: uploading a file to non-Comcast users while not simultaneously downloading parts of the same file. (In BitTorrent jargon, this is called “seeding”.) To get an idea of how odd this is, consider that an uploader who is experiencing blocking can apparently avoid the blocking by adding some download traffic.

It would likely be easier for Comcast to simply measure how much traffic each user is generating and drop the heaviest users’ packets, or just to discard packets at random (a tactic that falls most heavily on those who send and receive the most packets).

Beyond its choice of what to block, Comcast is using an unusual and nonstandard form of blocking.

There are well-established mechanisms for dealing with traffic congestion on the Internet. Networks are supposed to respond to congestion by dropping packets; endpoint computers notice that their packets are being dropped and respond by slowing their transmissions, thus relieving the congestion. The idea sounds simple, but getting the details right, so that the endpoints slow down just enough but not too much, and the network responds quickly to changes in traffic level but doesn’t overreact, required some very clever, subtle engineering.

What Comcast is doing instead is to cut off connections by sending forged TCP Reset packets to the endpoints. Reset packets are supposed to be used by one endpoint to tell the other endpoint that an unexplained, unrecoverable error has occurred and therefore communication cannot continue. Comcast’s equipment (apparently made by a company called Sandvine) seems to send both endpoints a Reset packet, purporting to come from the other endpoint, which causes both endpoints to break the connection. Doing this is a violation of the TCP protocol, which has at least two ill effects: it bypasses TCP’s well-engineered mechanisms for handling congestion, and it erodes the usefulness of Reset packets as true indicators of error.

People have apparently figured out already how to defeat this blocking, and presumably it won’t be long before BitTorrent clients incorporate anti-blocking measures.

It looks like Comcast is paying the price for trying to outsmart their customers.

Filed Under: Uncategorized Tagged With: , ,

The ease of applying for a home loan

October 19, 2007 by

I’m currently in the process of purchasing a new house. I called up a well-known national bank and said I wanted a mortgage. In the space of 30 minutes, I was pre-approved, had my rates locked in, and so forth. Pretty much the only identifying information I had to provide was the employer, salary, and social security number for myself and my wife, as well as some basic stats on our investment portfolio. Interestingly, the agent said that for people in my situation (sterling credit, paying more than 20% of the down payment out of our own pocket), they believe I’m highly unlikely to ever default on the loan. As a result, they do not need me to go the trouble of documenting my income or assets beyond what I told them over the phone. They’ll take my word for it.

(In an earlier post, I discussed my name and social security number having been stolen from where they had been kept in Ohio. Ohio gave me a free subscription to Debix, which claims to be able to intercept requests to read my credit report, calling my cell phone to ask for my permission. Why not? I signed up. Well, my cell phone never buzzed with any sort of call from Debix. Their service, whatever it does, had no effect here.)

Obviously, there’s a lot more to finalizing a loan and completing the purchase of a home than there is to getting approved for a loan and locking a rate. Nonetheless, it’s striking how little personal information I had to divulge to get this far into the game. Could somebody who knew my social security number use this mechanism to borrow money against my good credit and run away to a Carribean island with the proceeds? I would have to hope that there’s some kind of mechanism further down the pipeline to catch such fraud, but it’s not too hard to imagine ways to game this system, given what I’ve observed so far.

Needless to say, once this home purchase is complete, I’ll be freezing my credit report. Let’s just hope the freezing mechanism is more useful than Debix’s notification system.

(Sidebar: an $18 charge appeared on my credit card last month for a car rental agency that I’ve never used, claiming to have a “swipe” of my credit card. I challenged it, so now the anti-fraud division is allegedly attempting to recover the signed charge slip from the car rental agency. The mortgage agent, mentioned above, saw a note in my credit report on this and asked me if I had “challenged my bank”. I explained the circumstances and all was well. However, it’s interesting to note that the “challenge”, as it apparently appears in my credit report, doesn’t have any indication as to what’s being challenged or how significant it might be. Again, the agent basically took my word for it.)

Filed Under: Uncategorized Tagged With: ,

Radiohead Album Available for Free, But Fileshared Anyway

October 18, 2007 by

The band Radiohead is trying an interesting experiment, offering its new album In Rainbows for download and letting each customer decide how much to pay. You can name a price of zero and download the album for free, if you want, or you can pay whatever price you think is fair.

Now Andy Greenberg at Forbes is reporting that despite Radiohead’s free-if-you-choose offer, many users are downloading the album from P2P systems rather than getting it from the band’s site. Some commentators find this surprising, but in fact it should have been predictable.

Why are some people getting In Rainbows from P2P rather than the band’s site? Probably because they find P2P easier to use.

Radiohead’s site makes you click and click to get the music. First you have to click through a nearly content-free splash screen. Then you click through another splash screen telling you things you probably already knew. Then you click an “ORDER” button, and click away a dialog box telling you something you already knew. Then after some headscratching, you realize you need to click the “VIEW BASKET” button, which takes you to a form asking you to name your price, in U.K. currency. (They link you to a third-party site, offering a large collection of currency-conversion tools – several more clicks to find the one you want.) After choosing your price, you click “PAY NOW”, at which point you get to stare at a “You are currently in a queue” screen for a while, after which you set up an daccount enter some personal information (including your email address and mobile phone number) and agree to some terms of service (which are benign, but it’s more time and more clicks to verify that). Finally, you get to download the music.

It’s easy to see why somebody might prefer a P2P download. Leaving aside legal issues – and let’s face it, many people do – the moral argument against unauthorized P2P downloading seems pretty weak in this case, where downloaders aren’t depriving the band (or anyone else) of revenue.

This is an interesting natural experiment that tells us something about why people use P2P. If people normally choose P2P over authorized channels because P2P is cheaper, we would expect customers to shift toward the authorized channel when it offers a zero price. But if people choose P2P for convenience, then we’d expect a shift toward more P2P use for this album, because people have fewer moral qualms about P2P downloading this album than they would for a normal album. The clunkiness of Radiohead’s site improves the experiment by sharpening the ease-of-use factor.

It’s too early to tell how the experiment will come out, but news reports so far indicate that the ease-of-use factor is probably more important than some pundits think. This is yet more evidence that had the record industry embraced easy-to-use Internet music technologies early on, things would be very different now.

[UPDATE (Oct 21, 2007): Bill Zeller documents how technical issues completely prevent a large number of users from legally downloading In Rainbows from Radiohead’s site.]

Filed Under: Other Topics Tagged With: ,

Grokster Case Lumbers On; Judge To Issue Permanent Injunction

October 17, 2007 by

Remember the Grokster case? In which the Supreme Court found the filesharing companies Grokster and StreamCast liable for indirect copyright infringement, for “inducing” infringement by their users? You might have thought that case ended back in 2005. But it’s still going on, and the original judge just issued an interesting ruling. (Jason Schultz has a two part summary of the ruling.)

The issue now before the judge is what relief to grant the copyright-owner plaintiffs against StreamCast, which is the only defendant still standing. It’s apparently a given that the judge will eventually assess monetary damages against StreamCast. And you’d think these damages would be enough to kill StreamCast, so it’s not clear why StreamCast hasn’t just thrown in the towel, shut its doors, and handed over all its assets to the plaintiffs. Instead, StreamCast fought on, so the judge had to decide what kind of injunction, if any, to impose on StreamCast – that is, what rules would govern StreamCast’s future behavior.

The judge first considered the question of whether he could impose on StreamCast obligations (beyond payment of damages) that go beyond what the law requires of ordinary companies. Would he just award money damages and sternly command StreamCast not to break the law again; or would he go further and impose a permanent injunction? After a detailed legal analysis, he concluded that a permanent injunction was appropriate. StreamCast had actively promoted itself as a haven for infringement and “that bell cannot be unrung”.

The copyright-owner plaintiffs had asked for an injunction requiring StreamCast to apply all feasible anti-infringement technologies and to stop all infringment. StreamCast had built its own filtering technology which it said was effective enough, and much cheaper and more practical than commercially available alternatives.

The judge first rejected the plaintiff’s proposal that StreamCast be required to stop all infringement using its software. He recognized, correctly, that that would be impossible, so that such an injunction would be a death sentence for StreamCast.

Instead, the judge will require StreamCast to set up a filtering system that reasonably balances effectiveness and cost, with the strong emphasis on effectiveness. The precise details will be worked out with the help of a special master: an independent technical expert to be appointed by the judge. Which means yet more legal process to choose the special master, wait for the special master’s advice, and then order specific action from StreamCast.

All of this may be proper from a legal standpoint, but it seems unlikely to matter in practice. It’s hard to see how StreamCast can sustain a business given the legal and financial strain they must be under, and the likely ruinous monetary damages they’re still facing. I can understand why the plaintiffs might want to keep StreamCast on life support, in the hope of getting legal rulings that prove helpful elsewhere. But why does StreamCast keep fighting?

Filed Under: Uncategorized Tagged With: , , ,