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Harold and Kumar go to Comcastle

Save the Internet contests Laws of Physics

By Richard Bennett, 6 Nov 2007

Comment The coalition of the frustrated who comprise Save the Internet! have filed a multi-trillion dollar complaint with the FCC regarding Comcast's blatant exercise of, um, reasonable network management. The key fact seems to be this: if you live in a dream world of secret manipulative forces, evil wizards, fire-breathing dragons, scary ghosts and freaky monsters, the actions of ordinary businesses seem peculiar.

The complaint is a combination of science fiction and group therapy, with generous doses of pure paranoia thrown in.

The highlight:

The FCC should act immediately to enjoin Comcast’s secret discrimination and, even before deciding the merits, issue a temporary injunction requiring Comcast to stop degrading any applications.

Secret discrimination? However, the same complaint describes Comcast's network management practices as blatantly violating the FCC’s Internet Policy Statement. So which is it, secret or blatant?

And it gets better. The basis of the complaint is the claim that Comcast discriminates against BitTorrent in particular and Peer-to-Peer file swapping applications in general. The FCC's principles say that customers can run any application they want, and BitTorrent is an application. Hence, limiting the bandwidth P2P can use is breaking the law.

There are only two problems with this line of reasoning:

1) P2P applications aren't the only ones that Comcast throttles. The complaint itself admits that classic ftp has problems when trying to act as a server on the Comcast network, and further charges that Comcast's management has much wider effects:

While only Comcast knows the algorithm they use to decide when to forge RST packets, it is unlikely that they ever tested the plethora of applications that are potentially broken by that algorithm.

2) BitTorrent isn't disabled on the Comcast network, not even the seeding mode where it acts as a file server. I'm a Comcast customer, and as I write this I'm seeding several video files from the current season of a certain murder mystery series set in the most dangerous county in England. The key fact about BitTorrent that the reporters have missed is that it typically takes hours for large file or set of files to transfer, so a five to ten minute test doesn't say anything.

It's a nonsense complaint.

Shoot first, ask questions later?

So we have to ask if the FCC should be issuing injunctions before deciding on the merits of completely meritless complaints?

In a way I wish they would, so that Comcast's customers could see what their network would look like without any traffic management. I'll predict an outcome: people swapping illegal videos would be thrilled, everybody else would be super-pissed. And if that harms Comcast's business, then it would certainly be reasonable for the complainants to be required to compensate them.

And finally, how is Comcast to manage those situations that arrive in the course of operating a network millions of times a day when the traffic bound for a certain path exceeds the capacity of the path without degrading any applications? Surely some applications are going to be degraded, assuming the network's capacity is, you know, finite.

And this brings us to the funniest part of the complaint, the helpful suggestions about how to manage the Comcast network:

...if Comcast is concerned that the collective set of users running P2P applications are affecting quality of service for other users on a cable loop, they could readily set dynamic quotas for each user on the loop, so as to ensure that there is always bandwidth available for users who are not running P2P applications – and they could do so without interfering in protocol choice

As far as we know, this is exactly what Comcast is doing, setting dynamic upload quotas and enforcing them by preventing excessive numbers of upload streams from starting inside their private network.

The angels apparently believe there's a magic "quota" knob inside each cable modem owned or rented by each Comcast subscriber, but that's not the case. These modems can take a hard cap at boot time, but after that they lack a mechanism to prevent them from issuing excessive numbers of upstream transfer requests. That's undoubtedly a flaw in the definition of the DOCSIS protocol, but it's one that isn't going away simply because we may earnestly wish it would.

Who passed these Laws of Physics? Let's sue 'em

So what we have here is a demand that the FCC and Comcast repeal the laws of physics and provide unlimited non-delayed uploads to everybody everywhere on the Comcast network all the time. That's not going to happen no matter who's in charge of the agency.

The FCC should clarify the nature of "reasonable network management", and do so with sufficient force that the coalition is motivated to take its regulatory zeal elsewhere. In particular, that would mean saying that the following are presumed reasonable unless proved otherwise:

  • Any network management practice whose effect is to limit traffic load to the capacity of the network.
  • Any network management practice whose effect is to prevent a small number of users from dominating limited network resources and increasing delay for others.
  • Any network management practice necessary to keep the network operating within its stability parameters, which depend on the technology itself. E.g., Wi-Fi, DOCSIS, and Ethernet are all stable in different ranges of load.
  • All that virus and security stuff is also clearly fine.

I believe that we need to ignore the methods and concentrate on the effects because network equipment doesn't always allow multiple choices of the methods that manage traffic. The regulation advocates suggest, for example, that Comcast use "dynamic caps" to manage BitTorrent traffic rather than busy signals (TCP Reset is a digital busy signal). Dynamic caps aren't available in all DOCSIS modems, but the busy signal at the network portal clearly is.

In other words, Comcast manages its network according to what works, not what some weird coalition of angry lawyers and sweaty advocates think will work.

And I'd seriously like for the FCC to consider referring the complaint to the Justice Department for consideration of perjury charges. Some of the signatories have filled out "penalty of perjury" declarations after making irresponsible charges and claiming to be subject matter experts. I know this is pro forma, but some of their charges are so extreme that it would be wise to make examples of them. I don't expect that to happen, of course, because there's a wide latitude for lying in advocacy, but it would thrill me if it did.

Playing the politics game with the net

The bottom line here is that the Internet, which has succeeded largely because of its lack of regulation, has become the lust-object of a whole slew of regulators. Its existence and success are an affront to the livelihood and reputation of regulators everywhere, and they can't allow such a rebuke to stand. And sooner or later, the 535 regulators who make up the Congress will side with them. The Internet is too juicy a plum for them not to get their grubby little paws on it.

Net neutrality's father, Tim Wu, committed a gaffe recently and admitted that his movement is a power struggle for control of the Internet. Indeed it is. We can either allow the Internet to continue operating as it always has, under the control of engineers and users, or we can transfer control to lawyers, bureaucrats, and appliance testers. There are disturbing signs that the bureaucratization of the Internet is well underway. ICANN, the group that oversees domain name registrars and other sundry details, recently elected a lawyer to lead it in place of a former network engineer.

So enjoy it while it lasts.®

Richard Bennett is a network architect and occasional activist in Silicon Valley. He wrote the first standard for Ethernet over twisted-pair wiring and contributed to the standards for WiFi and the Ultra-Wideband wireless networks. His eleven-year old blog is on his personal website, at, where this article first appeared.

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