December 16, 2017

Archives for October 2007

Eavesdropping as a Telecom Profit Center

In 1980 AT&T was a powerful institution with a lucrative monopoly on transporting long-distance voice communications, but forbidden by law from permitting the government to eavesdrop without a warrant. Then in 1981 Judge Greene took its voice monopoly away, and in the 1980s and 90s the Internet ate the rest of its lunch. By 1996, Nicholas Negroponte wrote what many others also foresaw: “Shipping bits will be a crummy business. Transporting voice will be even worse. By 2020 … competition will render bandwidth a commodity of the worst kind, with no margins and no real basis for charging anything.

During the 1980s and 90s, AT&T cleverly got out of any business except shipping commodity bits: in 1981 it (was forced to) split off its regional phone companies; in 1996 it (voluntarily) split off its equipment-making arm as Lucent Technologies; in 2000-2001 it sold off its Wireless division to raise cash. Now AT&T long-distance bit-shipping is just a division of the former SBC, renamed AT&T.

What profit centers are left in shipping commodity bits? The United States Government spends 44 billion dollars a year on its spy agencies. It’s very plausible that the NSA is willing to pay $100 million or more for a phone/internet company to install a secret room where the NSA can spy on all the communications that pass through. A lawsuit by the EFF alleges such a room, and its existence was implicitly confirmed by the Director of National Intelligence in an interview with the El Paso Times. We know the NSA spends at least $200 million a year on information-technology outsourcing and some of this goes to phone companies such as Verizon.

Therefore, if it’s true that AT&T has such a secret room, then it may be simply that this is the only way AT&T knows how to make money off of shipping bits: it sells to the government all the information that passes through. Furthermore, economics tells us that in a commodity market, if one vendor is able to lower its price below cost, then other vendors must follow unless they also are able to make up the difference somehow. That is, there will be substantial economic pressure on all the other telecoms to accept the government’s money in exchange for access to everybody’s mail, Google searches, and phone calls.

In the end, it could be that the phone companies that cooperated with the NSA did so not for reasons of patriotism, or because their arms were twisted, but because the NSA came with a checkbook. Taking the NSA’s money may be the only remaining profit center in bit-shipping.

AT&T Explains Guilt by Association

According to government documents studied by The New York Times, the FBI asked several phone companies to analyze phone-call patterns of Americans using a technology called “communities of interest”. Verizon refused, saying that it didn’t have any such technology. AT&T, famously, did not refuse.

What is the “communities of interest” technology? It’s spelled out very clearly in a 2001 research paper from AT&T itself, entitled “Communities of Interest” (by C. Cortes, D. Pregibon, and C. Volinsky). They use high-tech data-mining algorithms to scan through the huge daily logs of every call made on the AT&T network; then they use sophisticated algorithms to analyze the connections between phone numbers: who is talking to whom? The paper literally uses the term “Guilt by Association” to describe what they’re looking for: what phone numbers are in contact with other numbers that are in contact with the bad guys?

When this research was done, back in the last century, the bad guys where people who wanted to rip off AT&T by making fraudulent credit-card calls. (Remember, back in the last century, intercontinental long-distance voice communication actually cost money!) But it’s easy to see how the FBI could use this to chase down anyone who talked to anyone who talked to a terrorist. Or even to a “terrorist.”

Here are a couple of representative diagrams from the paper:

Fig. 4. Guilt by association – what is the shortest path to a fraudulent node?

Fig. 5. A guilt by association plot. Circular nodes correspond to wireless service accounts while rectangular nodes are conventional land line accounts. Shaded nodes have been previously labeled as fraudulent by network security associates.

Comcast and Net Neutrality

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.