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banking transactions and employee communications.
Similarly, someone could go through old data with new analytical tools. Think about genetic data. There’s not yet a lot we can learn from someone’s genetic data, but ten years from now—who knows? We saw something similar happen during the Tour de France doping scandals; blood taken from riders years earlier was tested with new technologies, and widespread doping was detected.
The NSA stores a lot of historical data, which I’ll talk about more in Chapter 5. We know that in 2008 a database called XKEYSCORE routinely held voice and e-mail content for just three days, but it held metadata for a month. One called MARINA holds a year’s worth of people’s browsing history. Another NSA database, MYSTIC, was able to store recordings of all the phone conversations for Bermuda. The NSA stores telephone metadata for five years.
These storage limits pertain to the raw trove of all data gathered. If an NSA analyst touches something in the database, the agency saves it for much longer. If your data is the result of a query into these databases, your data is saved indefinitely. If you use encryption, your data is saved indefinitely. If you use certain keywords, your data is saved indefinitely.
How long the NSA stores data is more a matter of storage capacity than a respect for privacy. We know the NSA needed to increase its storage capacity to hold all the cell phone location data it was collecting. As data storage gets cheaper, assume that more of this data will be stored longer. This is the point of the NSA’s Utah Data Center.
The FBI stores our data, too. During the course of a legitimate investigation in 2013, the FBI obtained a copy of all the data on a site called Freedom Hosting, including stored e-mails. Almost all the data was unrelated to the investigation, but the FBI kept a copy of the entire site and has been accessing it for unrelated investigations ever since. The state of New York retains license plate scanning data for at least five years and possibly indefinitely.
Any data—Facebook history, tweets, license plate scanner data—can basically be retained forever, or until the company or government agency decides to delete it. In 2010, different cell phone companies held text messages for durations ranging from 90 days to 18 months. AT&T beat them all, hanging on to the data for seven years.
MAPPING RELATIONSHIPS
Mass-surveillance data permits mapping of interpersonal relationships. In 2013, when we first learned that the NSA was collecting telephone calling metadata on every American, there was much ado about so-called hop searches and what they mean. They’re a new type of search, theoretically possible before computers but only really practical in a world of mass surveillance. Imagine that the NSA is interested in Alice. It will collect data on her, and then data on everyone she communicates with, and then data on everyone they communicate with, and then data on everyone they communicate with. That’s three hops away from Alice, which is the maximum the NSA worked with.
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The intent of hop searches is to map relationships and find conspiracies. Making sense of the data requires being able to cull out the overwhelming majority of innocent people who are caught in this dragnet, and the phone numbers common to unrelated people: voice mail services, pizza restaurants, taxi companies, and so on.
NSA documents note that the agency had 117,675 “active surveillance targets” on one day in 2013. Even using conservative estimates of how many conversants each person has and how much they overlap, the total number of people being surveilled by this system easily exceeded 20 million. It’s the classic “six degrees of separation” problem; most of us are only a few hops away from everyone else. In 2014, President Obama directed the NSA to conduct two-hop analysis only on telephone metadata collected under one particular program, but he didn’t place any restrictions on NSA hops for all the other data it collects.
Metadata from various sources is great for mapping relationships. Most of us use the Internet for social interaction, and our relationships show up in that. This is what both the NSA and Facebook do, and it’s why the latter is so unnervingly accurate when it suggests people you might know whom you’re not already Facebook friends with. One of Facebook’s most successful advertising programs involves showing ads not just to people who Like a particular page or product, but to their friends and to friends of their friends.
FINDING US BY WHAT WE DO
Once you have collected data on everyone, you can search for individuals based on their behavior. Maybe you want to find everyone who frequents a certain gay bar, or reads about a particular topic, or has a particular political belief. Corporations do this regularly, using masssurveillance data to find potential customers with particular characteristics, or looking for people to hire by searching for people who have published on a particular topic.
One can search for things other than names and other personal identifiers like identification numbers, phone numbers, and so on. Google, for example, searches all of your Gmail and uses keywords it finds to more intimately understand you, for advertising purposes. The NSA does something similar: what it calls “about” searches. Basically, it searches the contents of everyone’s communications for a particular name or word—or maybe a phrase. So in addition to examining Alice’s data and the data of everyone within two or three hops of her, it can search everyone else—the entire database of communications—for mentions of her name. Or if it doesn’t know a name, but knows the name of a particular location or project, or a code name that someone has used, it can search on that. For example, the NSA targets people who search for information on popular Internet privacy and anonymity tools.
We don’t know the details, but the NSA chains together hops based on any connection, not just phone connections. This could include being in the same location as a target, having the same calling pattern, and so on. These types of searches are made possible by having access to everyone’s data.
You can use mass surveillance to find individuals. If you know that a particular person was at a specific restaurant one evening, a train station three days later in the afternoon, and a hydroelectric plant the next morning, you can query a database of everyone’s cell phone locations, and anyone who fits those characteristics will pop up.
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You can also search for anomalous behavior. Here are four examples of how the NSA uses cell phone data.
- The NSA uses cell phone location information to track people whose movements intersect. For example, assume that the NSA is interested in Alice. If Bob is at the same restaurant as Alice one evening, and then at the same coffee shop as Alice a week later, and at the same airport as Alice a month later, the system will flag Bob as a potential associate of Alice’s, even if the two have never communicated electronically.
- The NSA tracks the locations of phones that are carried around by US spies overseas. Then it determines whether there are any other cell phones that follow the agents’ phones around. Basically, the NSA checks whether anyone is tailing those agents.
- The NSA has a program where it trawls through cell phone metadata to spot phones that are turned on, used for a while, and then turned off and never used again. And it uses the phones’ usage patterns to chain them together. This technique is employed to find “burner” phones used by people who wish to avoid detection.
- The NSA collects data on people who turn their phones off, and for how long. It then collects the locations of those people when they turned their phones off, and looks for others nearby who also turned their phones off for a similar period of time. In other words, it looks for secret meetings.
I’ve already discussed the government of Ukraine using cell phone location data to find everybody who attended an antigovernment demonstration, and the Michigan police using it to find everyone who was near a planned labor union protest site. The FBI has used this data to find phones that were used by a particular target but not otherwise associated with him.
Corporations do some of this as well. There’s a technique called geofencing that marketers use to identify people who are near a particular business so as to deliver an ad to them. A single geofencing company, Placecast, delivers location-based ads to ten million phones in the US and UK for chains like Starbucks, Kmart, and Subway. Microsoft does the same thing to people passing within ten miles of some of its stores; it works with the company NinthDecimal. Sense Networks uses location data to create individual profiles.
CORRELATING DIFFERENT DATA SETS
Vigilant Solutions is one of the companies that collect license plate data from cameras. It has plans to augment this system with other algorithms for automobile identification, systems of facial recognition, and information from other databases. The result would be a much more powerful surveillance platform than a simple database of license plate scans, no matter how extensive, could ever be.
News stories about mass surveillance are generally framed in terms of data collection, but miss the story about data correlation: the linking of identities across different data sets to draw inferences from the combined data. It’s not just that inexpensive drones with powerful cameras will become increasingly common. It’s the drones plus facial recognition software that allows the system to identify people automatically, plus the large databases of tagged photos—from driver’s licenses, Facebook, newspapers, high school yearbooks—that will provide reference images for that software. It’s also the ability to correlate that identification with numerous other databases, and the ability to store all that data indefinitely. Ubiquitous surveillance is the result of multiple streams of mass surveillance tied together.
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I have an Oyster card that I use to pay for public transport while in London. I’ve taken pains to keep it cash-only and anonymous. Even so, if you were to correlate the usage of that card with a list of people who visit London and the dates—whether that list is provided by the airlines, credit card companies, cell phone companies, or ISPs—I’ll bet that I’m the only person for whom those dates correlate perfectly. So my “anonymous” movement through the London Underground becomes nothing of the sort.
Snowden disclosed an interesting research project from the CSEC—that’s the Communications Security Establishment Canada, the country’s NSA equivalent—that demonstrates the value of correlating different streams of surveillance information to find people who are deliberately trying to evade detection.
A CSEC researcher, with the cool-sounding job title of “tradecraft developer,” started with two weeks’ worth of Internet identification data: basically, a list of user IDs that logged on to various websites. He also had a database of geographic locations for different wireless networks’ IP addresses. By putting the two databases together, he could tie user IDs logging in from different wireless networks to the physical location of those networks. The idea was to use this data to find people. If you know the user ID of some surveillance target, you can set an alarm when that target uses an airport or hotel wireless network and learn when he is traveling. You can also identify a particular person who you know visited a particular geographical area on a series of dates and times. For example, assume you’re looking for someone who called you anonymously from three different pay phones. You know the dates and times of the calls, and the locations of those pay phones. If that person has a smartphone in his pocket that automatically logs into wireless networks, then you can correlate that log-in database with dates and times you’re interested in and the locations of those networks. The odds are that there will only be one match.
Researchers at Carnegie Mellon University did something similar. They put a camera in a public place, captured images of people walking past, identified them with facial recognition software and Facebook’s public tagged photo database, and correlated the names with other databases. The result was that they were able to display personal information about a person in real time as he or she was walking by. This technology could easily be available to anyone, using smartphone cameras or Google Glass.
Sometimes linking identities across data sets is easy; your cell phone is connected to your name, and so is your credit card. Sometimes it’s harder; your e-mail address might not be connected to your name, except for the times people refer to you by name in e-mail. Companies like Initiate Systems sell software that correlates data across multiple data sets; they sell to both governments and corporations. Companies are also correlating your online behavior with your offline actions. Facebook, for example, is partnering with the data brokers Acxiom and Epsilon to match your online profile with in-store purchases.
Once you can correlate different data sets, there is a lot you can do with them. Imagine building up a picture of someone’s health without ever looking at his patient records. Credit card records and supermarket affinity cards reveal what food and alcohol he buys, which restaurants he eats at, whether he has a gym membership, and what nonprescription items he buys at a pharmacy. His phone reveals how often he goes to that gym, and his activity tracker reveals his activity level when he’s there. Data from websites reveal what medical terms he’s searched on. This is how a company like ExactData can sell lists of people who date online, people who gamble, and people who suffer from anxiety, incontinence, or erectile dysfunction.
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PIERCING OUR ANONYMITY
When a powerful organization is eavesdropping on significant portions of our electronic infrastructure and can correlate the various surveillance streams, it can often identify people who are trying to hide. Here are four stories to illustrate that.
- Chinese military hackers who were implicated in a broad set of attacks against the US government and corporations were identified because they accessed Facebook from the same network infrastructure they used to carry out their attacks.
- Hector Monsegur, one of the leaders of the LulzSec hacker movement under investigation for breaking into numerous commercial networks, was identified and arrested in 2011 by the FBI. Although he usually practiced good computer security and used an anonymous relay service to protect his identity, he slipped up once. An inadvertent disclosure during a chat allowed an investigator to track down a video on YouTube of his car, then to find his Facebook page.
- Paula Broadwell, who had an affair with CIA director David Petraeus, similarly took extensive precautions to hide her identity. She never logged in to her anonymous e-mail service from her home network. Instead, she used hotel and other public networks when she e-mailed him. The FBI correlated registration data from several different hotels—and hers was the common name.
- A member of the hacker group Anonymous called “w0rmer,” wanted for hacking US law enforcement websites, used an anonymous Twitter account, but linked to a photo of a woman’s breasts taken with an iPhone. The photo’s embedded GPS coordinates pointed to a house in Australia. Another website that referenced w0rmer also mentioned the name Higinio Ochoa. The police got hold of Ochoa’s Facebook page, which included the information that he had an Australian girlfriend. Photos of the girlfriend matched the original photo that started all this, and police arrested w0rmer aka Ochoa.
Maintaining Internet anonymity against a ubiquitous surveillor is nearly impossible. If you forget even once to enable your protections, or click on the wrong link, or type the wrong thing, you’ve permanently attached your name to whatever anonymous provider you’re using. The level of operational security required to maintain privacy and anonymity in the face of a focused and determined investigation is beyond the resources of even trained government agents. Even a team of highly trained Israeli assassins was quickly identified in Dubai, based on surveillance camera footage around the city.
The same is true for large sets of anonymous data. We might naïvely think that there are so many of us that it’s easy to hide in the sea of data. Or that most of our data is anonymous. That’s not true. Most techniques for anonymizing data don’t work, and the data can be de-anonymized with surprisingly little information.
In 2006, AOL released three months of search data for 657,000 users: 20 million searches in all. The idea was that it would be useful for researchers; to protect people’s identity, they replaced names with numbers. So, for example, Bruce Schneier might be 608429. They were surprised when researchers were able to attach names to numbers by correlating different items in individuals’ search history.
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In 2008, Netflix published 10 million movie rankings by 500,000 anonymized customers, as part of a challenge for people to come up with better recommendation systems than the one the company was using at that time. Researchers were able to deanonymize people by comparing rankings and time stamps with public rankings and time stamps in the Internet Movie Database. These might seem like special cases, but correlation opportunities pop up more frequently than you might think. Someone with access to an anonymous data set of telephone records, for example, might partially de-anonymize it by correlating it with a catalog merchant’s telephone order database. Or Amazon’s online book reviews could be the key to partially de-anonymizing a database of credit card purchase details. Using public anonymous data from the 1990 census, computer scientist Latanya Sweeney found that 87% of the population in the United States, 216 million of 248 million people, could likely be uniquely identified by their five-digit ZIP code combined with their gender and date of birth. For about half, just a city, town, or municipality name was sufficient. Other researchers reported similar results using 2000 census data. Google, with its database of users’ Internet searches, could de-anonymize a public database of Internet purchases, or zero in on searches of medical terms to de-anonymize a public health database. Merchants who maintain detailed customer and purchase information could use their data to partially de-anonymize any large search engine’s search data. A data broker holding databases of several companies might be able to deanonymize most of the records in those databases. Researchers have been able to identify people from their anonymous DNA by comparing the data with information from genealogy sites and other sources. Even something like Alfred Kinsey’s sex research data from the 1930s and 1940s isn’t safe. Kinsey took great pains to preserve the anonymity of his subjects, but in 2013, researcher Raquel Hill was able to identify 97% of them. It’s counterintuitive, but it takes less data to uniquely identify us than we think. Even though we’re all pretty typical, we’re nonetheless distinctive. It turns out that if you eliminate the top 100 movies everyone watches, our movie-watching habits are all pretty individual. This is also true for our book-reading habits, our Internet-shopping habits, our telephone habits, and our web-searching habits. We can be uniquely identified by our relationships. It’s quite obvious that you can be uniquely identified by your location data. With 24/7 location data from your cell phone, your name can be uncovered without too much trouble. You don’t even need all that data; 95% of Americans can be identified by name from just four time/date/location points. The obvious countermeasures for this are, sadly, inadequate. Companies have anonymized data sets by removing some of the data, changing the time stamps, or inserting deliberate errors into the unique ID numbers they replaced names with. It turns out, though, that these sorts of tweaks only make de-anonymization slightly harder. This is why regulation based on the concept of “personally identifying information” doesn’t work. PII is usually defined as a name, unique account number, and so on, and
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special rules apply to it. But PII is also about the amount of data; the more information someone has about you, even anonymous information, the easier it is for her to identify you.
For the most part, our protections are limited to the privacy policies of the companies we use, not by any technology or mathematics. And being identified by a unique number often doesn’t provide much protection. The data can still be collected and correlated and used, and eventually we do something to attach our name to that “anonymous” data record.
In the age of ubiquitous surveillance, where everyone collects data on us all the time, anonymity is fragile. We either need to develop more robust techniques for preserving anonymity, or give up on the idea entirely.
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The Business of Surveillance
One of the most surprising things about today’s cell phones is how many other things they also do. People don’t wear watches, because their phones have a clock. People don’t carry cameras, because they come standard in most smartphones.
That camera flash can also be used as a flashlight. One of the flashlight apps available for Android phones is Brightest Flashlight Free, by a company called GoldenShores Technologies, LLC. It works great and has a bunch of cool features. Reviewers recommended it to kids going trick-or-treating. One feature that wasn’t mentioned by reviewers is that the app collected location information from its users and allegedly sold it to advertisers.
It’s actually more complicated than that. The company’s privacy policy, never mind that no one read it, actively misled consumers. It said that the company would use any information collected, but left out that the information would be sold to third parties. And although users had to click “accept” on the license agreement they also didn’t read, the app started collecting and sending location information even before people clicked.
This surprised pretty much all of the app’s 50 million users when researchers discovered it in 2012. The US Federal Trade Commission got involved, forcing the company to clean up its deceptive practices and delete the data it had collected. It didn’t fine the company, though, because the app was free.
Imagine that the US government passed a law requiring all citizens to carry a tracking device. Such a law would immediately be found unconstitutional. Yet we carry our cell phones everywhere. If the local police department required us to notify it whenever we made a new friend, the nation would rebel. Yet we notify Facebook. If the country’s spies demanded copies of all our conversations and correspondence, people would refuse. Yet we provide copies to our e-mail service providers, our cell phone companies, our social networking platforms, and our Internet service providers.
The overwhelming bulk of surveillance is corporate, and it occurs because we ostensibly agree to it. I don’t mean that we make an informed decision agreeing to it; instead, we accept it either because we get value from the service or because we are offered a package deal that includes surveillance and don’t have any real choice in the matter. This is the bargain I talked about in the Introduction.
This chapter is primarily about Internet surveillance, but remember that everything is —or soon will be—connected to the Internet. Internet surveillance is really shorthand for surveillance in an Internet-connected world.
INTERNET SURVEILLANCE
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The primary goal of all this corporate Internet surveillance is advertising. There’s a little market research and customer service in there, but those activities are secondary to the goal of more effectively selling you things. Internet surveillance is traditionally based on something called a cookie. The name sounds benign, but the technical description “persistent identifier” is far more accurate. Cookies weren’t intended to be surveillance devices; rather, they were designed to make surfing the web easier. Websites don’t inherently remember you from visit to visit or even from click to click. Cookies provide the solution to this problem. Each cookie contains a unique number that allows the site to identify you. So now when you click around on an Internet merchant’s site, you keep telling it, “I’m customer #608431.” This allows the site to find your account, keep your shopping cart attached to you, remember you the next time you visit, and so on. Companies quickly realized that they could set their own cookies on pages belonging to other sites—with their permission and by paying for the privilege—and the third-party cookie was born. Enterprises like DoubleClick (purchased by Google in 2007) started tracking web users across many different sites. This is when ads started following you around the web. Research a particular car or vacation destination or medical condition, and for weeks you’ll see ads for that car or city or a related pharmaceutical on every commercial Internet site you visit. This has evolved into a shockingly extensive, robust, and profitable surveillance architecture. You are being tracked pretty much everywhere you go on the Internet, by many companies and data brokers: ten different companies on one site, a dozen on another. Facebook tracks you on every site with a Facebook Like button (whether you’re logged in to Facebook or not), and Google tracks you on every site that has a Google Plus +1 button or that simply uses Google Analytics to monitor its own web traffic. Most of the companies tracking you have names you’ve never heard of: Rubicon Project, AdSonar, Quantcast, Pulse 260, Undertone, Traffic Marketplace. If you want to see who’s tracking you, install one of the browser plugins that let you monitor cookies. I guarantee you will be startled. One reporter discovered that 105 different companies tracked his Internet use during one 36-hour period. In 2010, a seemingly innocuous site like Dictionary.com installed over 200 tracking cookies on your browser when you visited. It’s no different on your smartphone. The apps there track you as well. They track your location, and sometimes download your address book, calendar, bookmarks, and search history. In 2013, the rapper Jay-Z and Samsung teamed up to offer people who downloaded an app the ability to hear the new Jay-Z album before release. The app required the ability to view all accounts on the phone, track the phone’s location, and track who the user was talking to on the phone. And the Angry Birds game even collects location data when you’re not playing. Broadband companies like Comcast also conduct surveillance on their users. These days they’re mostly monitoring to see whether you illegally download copyrighted songs and videos, but other applications aren’t far behind. Verizon, Microsoft, and others are working on a set-top box that can monitor what’s going on in the room, and serve ads
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based on that information.
It’s less Big Brother, and more hundreds of tattletale little brothers.
Today, Internet surveillance is far more insistent than cookies. In fact, there’s a minor arms race going on. Your browser—yes, even Google Chrome—has extensive controls to block or delete cookies, and many people enable those features. DoNotTrackMe is one of the most popular browser plug-ins. The Internet surveillance industry has responded with “flash cookies”—basically, cookie-like files that are stored with Adobe’s Flash player and remain when browsers delete their cookies. To block those, you can install FlashBlock. But there are other ways to uniquely track you, with esoteric names like evercookies, canvas fingerprinting, and cookie synching. It’s not just marketers; in 2014, researchers found that the White House website used evercookies, in violation of its own privacy policy. I’ll give some advice about blocking web surveillance in Chapter 15.
Cookies are inherently anonymous, but companies are increasingly able to correlate them with other information that positively identifies us. You identify yourself willingly to lots of Internet services. Often you do this with only a username, but increasingly usernames can be tied to your real name. Google tried to compel this with its “real name policy,” which mandated that users register for Google Plus with their legal names, until it rescinded that policy in 2014. Facebook pretty much demands real names. Anytime you use your credit card number to buy something, your real identity is tied to any cookies set by companies involved in that transaction. And any browsing you do on your smartphone is tied to you as the phone’s owner, although the website might not know it.
FREE AND CONVENIENT
Surveillance is the business model of the Internet for two primary reasons: people like free, and people like convenient. The truth is, though, that people aren’t given much of a choice. It’s either surveillance or nothing, and the surveillance is conveniently invisible so you don’t have to think about it. And it’s all possible because US law has failed to keep up with changes in business practices.
Before 1993, the Internet was entirely noncommercial, and free became the online norm. When commercial services first hit the Internet, there was a lot of talk about how to charge for them. It quickly became clear that, except for a few isolated circumstances like investment and porn websites, people weren’t willing to pay even a small amount for access. Much like the business model for television, advertising was the only revenue model that made sense, and surveillance has made that advertising more profitable. Websites can charge higher prices for personally targeted advertising than they can for broadcast advertising. This is how we ended up with nominally free systems that collect and sell our data in exchange for services, then blast us with advertising.
“Free” is a special price, and there has been all sorts of psychological research showing that people don’t act rationally around it. We overestimate the value of free. We consume more of something than we should when it’s free. We pressure others to consume it. Free warps our normal sense of cost vs. benefit, and people end up trading their