Over the years, there’s been talk on and off about a technology called Deep Packet Inspection , but apart from sounding like the title of sysadmin-themed porn, why should you care?
Technically, DPI is what happens when an ISP looks past the headers, or metadata, of the packets that carry information all around the Internet and into the content. On its own, looking doesn’t hamper the Internet, but only that packet header is required by the machines that need to pump the cats through the series of tubes .
Could Internet service providers be watching you?
Like all technologies, DPI isn’t inherently good or bad, but potentially either. Good uses include cleaning up spam and viruses, and useful traffic shaping. Bad uses include dystopian control of digital expression and perfect totalitarian surveillance .
But let’s break that down a bit. Because DPI looks into each packet, it can be used, as in the case of the National Security Agency ( NSA ) warrantless wiretaps, to copy every packet. In the case of Comcast, it was used to identify Bit-Torrent traffic and disrupt it. In America, it’s been used to very specifically target advertising. In other countries known to use DPI, like China and Bahrain, it could be (and likely is) used for specifically targeting political activists.
DPI is the technology that allows violation of net neutrality , lets ISPs throttle competing services, and rights-holders to comb the net looking for content. But despite the dark side, given how easy and useful for companies it is, it’s inevitable. Without rigorous legal protection, you’ll never know if it’s used on you.
The only thing that slows down DPI at all is encryption, coded messages ISPs can look at but never make sense of. Fortunately, encryption tools are becoming available to everyone. DPI is the future of the net—and so is you encrypting your way back to free speech and privacy.