The dust-up over internet privacy has returned to Capitol Hill.
The centerpiece of Thursday's hearing of the US House of Representatives' Subcommittee on Communications, Technology, and the Internet was - as it has been in the past - deep packet inspection (DPI), i.e. looking inside an internet packet to determine its contents.
Conversely, shallow packet inspection merely looks at a packet's header to determine routing information and to provide stats for analysis. DPI, on the other hand, inspects the proverbial whole enchilada, allowing the inspector to determine the contents of the web traffic.
Whatever some may think, DPI is not - in and of itself - nefarious. DPI can, for example, be a useful tool in the hands of a corporate security officer who needs to keep an eye on what's flowing through his network.
It's when DPI snoops into a user's internet traffic without that user's consent that it becomes problematic. And then there's the matter of what constitutes "consent." Here the argument is the old familiar opt-in versus opt-out debate. Think of Phorm and NebuAd, those ad serving operations that have employed deep packet inspection from inside US and UK ISPs.
Let's say that your ISP has an opt-out clause buried deeply on page 32 of its legally required privacy-policy statement. You, of course, have never seen it - you just clicked the "Agree" button when you signed up. In that case, your DPI-using ISP can see that you frequent Bangers 'n' Mash.com and target you with ads for other greasy goodies.
Thursday's subcommittee meeting focused on this sort of ISP-based DPI. It began with a statement (PDF) by its chairman, Rep. Rick Boucher, a Democrat from Virginia, in which he said that DPI's "privacy intrusion potential is nothing short of frightening. The thought that a network operator could track a user’s every move on the Internet, record the details of every search and read every email or attached document is alarming."
Boucher's concern was applauded and echoed by Leslie Harris, president and CEO of the Center for Democracy & Technology (CDT). In her testimony (PDF) she said that "The use of DPI technology [by ISPs]...raises profound questions about the future of privacy, openness, and innovation online."
Saying that shallow packet inspection is the equivalent of a postal worker reading an envelope's address in order to deliver it to the correct recipient, she continued the analogy by saying that "Deep packet inspection is the equivalent of postal employees opening envelopes and reading the letters inside."
But before you think of Harris as a pure-as-the-driven-snow advocate of personal internet privacy, know that Google and Yahoo! are CDT funders - not huge donors, to be sure, but supporters nonetheless. And Google has its own self-serving ideas about internet privacy.
Kyle McSlarrow, president and CEO of the National Cable & Telecommunications Association, was of a different mind. In his testimony (PDF), he offered the opinion that "[Deep] Packet inspection serves a number of pro-consumer purposes."
McSlarrow then went on to enumerate how DPI can help consumers, including preventing spam and malware, identifying packets that contain viruses or worms, proactively preventing Trojan-horse infections, preventing identity theft and phishing, and preventing proxy hijacks ("a technique used by criminals").
He also sees DPI's benefit to ISPs, such as enabling network diagnostics and capacity planning, and to law enforcement. Finally, he threw in the traditional "think of the children" argument, saying that in the future DPI could be used for enhanced parental controls.
Marc Rotenberg, executive director, of the Electronic Privacy Information Center (EPIC), wasn't buying it. His testimony (PDF) cited the US Wiretap Act, which specifically criminalizes "any person who...intentionally intercepts, endeavors to intercept, or procures any other person to intercept or endeavor to intercept, any wire, oral, or electronic communication."
And so the arguments continue. Rep. Boucher plans a a joint hearing with the Subcommittee on Commerce, Trade and Consumer Protection in early summer "to examine online privacy, including behavioral advertising, at which Internet based companies will be invited to testify." ®