Features

net.wars: An affair to remember

Politicians change; policies remain the same. Or if, they don't, they return like the monsters in horror movies that end with the epigraph, "It's still out there…"

Cut to 1994, my first outing to the Computers, Freedom, and Privacy conference. I saw: passionate discussions about the right to strong cryptography. The counterargument from government and law enforcement and security service types was that yes, strong cryptography was a fine and excellent thing at protecting communications from prying eyes and for that very reason we needed key escrow to ensure that bad people couldn't say evil things to each other in perfect secrecy. The listing of organized crime, terrorists, drug dealers, and pedophiles as the reasons why it was vital to ensure access to cleartext became so routine that physicist Timothy May dubbed them "The Four Horsemen of the Infocalypse". Cypherpunks opposed restrictions on the use and distribution of strong crypto; government types wanted at the very least a requirement that copies of secret cryptographic keys be provided and held in escrow against the need to decrypt in case of an investigation. The US government went so far as to propose a technology of its own, complete with back door, called the Clipper chip.

Eventually, the Clipper chip was cracked by Matt Blaze, and the needs of electronic commerce won out over the paranoia of the military and restrictions on the use and export of strong crypto were removed.

Cut to 2000 and the run-up to the passage of the UK's Regulation of Investigatory Powers Act. Same Four Horsemen, same arguments. Eventually RIPA passed with the requirement that individuals disclose their cryptographic keys – but without key escrow. Note that it's just in the last couple of months that someone – a teenager – has gone to jail in the UK for the first time for refusing to disclose their key.

It is not just hype by security services seeking to evade government budget cuts to say that we now have organized cybercrime. Stuxnet rightly has scared a lot of people into recognizing the vulnerabilities of our infrastructure. And clearly we've had terrorist attacks. What we haven't had is a clear demonstration by law enforcement that encrypted communications have impeded the investigation.

A second and related strand of argument holds that communications data – that is traffic data such as email headers and Web addresses – must be retained and stored for some lengthy period of time, again to assist law enforcement in case an investigation is needed. As the Foundation for Information Policy Research and Privacy International have consistently argued for more than ten years, such traffic data is extremely revealing. Yes, that's why law enforcement wants it; but it's also why the American Library Association has consistently opposed handing over library records. Traffic data doesn't just reveal who we talk to and care about; it also reveals what we think about. And because such information is of necessity stored without context, it can also be misleading. If you already think I'm a suspicious person, the fact that I've been reading proof-of-concept papers about future malware attacks sounds like I might be a danger to cybersociety. If you know I'm a journalist specializing in technology matters, that doesn't sound like so much of a threat.

And so to this week. The former head of the Department of Homeland Security, Michael Chertoff, at the RSA Security Conference compared today's threat of cyberattack to nuclear proliferation. The US's Secure Flight program is coming into effect, requiring airline passengers to provide personal data for the US to check 72 hours in advance (where possible). Both the US and UK security services are proposing the installation of deep packet inspection equipment at ISPs. And language in the UK government's Strategic Defence and Security Review (PDF) review has led many to believe that what's planned is the revival of the we-thought-it-was-dead Interception Modernisation Programme

Over at Light Blue Touchpaper, Ross Anderson links many of these trends and asks if we will see a resumption of the crypto wars of the mid-1990s. I hope not; I've listened to enough quivering passion over mathematics to last an Internet lifetime.

But as he says it's hard to see one without the other. On the face of it, because the data "they" want to retain is traffic data and note content, encryption might seem irrelevant. But a number of trends are pushing people toward greater use of encryption. First and foremost is the risk of interception; many people prefer (rightly) to use secured https, SSH, or VPN connections when they're working over public wi-fi networks. Others secure their connections precisely to keep their ISP from being able to analyze their traffic. If data retention and deep packet inspection become commonplace, so will encrypted connections.

And at that point, as Anderson points out, the focus will return to long-defeated ideas like key escrow and restrictions on the use of encryption. The thought of such a revival is depressing; implementing any of them would be such a regressive step. If we're going to spend billions of pounds on the Internet infrastructure – in the UK, in the US, anywhere else – it should be spent on enhancing robustness, reliability, security, and speed, not building the technological infrastructure to enable secret, warrantless wiretapping.