Computing Applications News

Ephemeral Data

Privacy issues can evaporate when embarrassing content does likewise.
Ephemeral Data, photo illustration
  1. Introduction
  2. Ephemeral Data in the Enterprise
  3. Is Data Really Ephemeral?
  4. Further Reading
  5. Videos
  6. Author
Ephemeral Data, photo illustration

As people have discovered on social media sites, the past sometimes comes back to haunt you—and can destroy lives in the process. Recently, for example, a Florida woman made headlines by filing what is believed to be the first "revenge porn" suit in that state against an ex-boyfriend for posting naked photos of her years after their breakup. The woman is now trying to get a law passed in Florida that would criminalize "cyber stalking."

Such measures may be prompting some people to think twice as they send photos, email, videos, and texts they assume are between themselves and another party only. However, not everyone is that circumspect. Regardless of where you fall, the introduction of a new class of apps means users no longer have to wonder what gets saved by the recipient and what doesn’t; these apps are designed to protect your privacy by making content disappear after a defined period. So-called ephemeral data is being made possible through apps provided by companies including Snapchat, Gryphn, Wickr, and Silent Circle.

"People are becoming increasingly aware that some social media platforms keep a permanent record of all that they post and all they comment on or rank or like or otherwise display in their feeds and profiles, so the market is responding with new services that are more evanescent," observes Lee Raine, director of the Pew Research Center’s Internet & American Life Project, a non-profit, non-partisan "fact tank" that studies the social impact of the Internet. Apps that make data ephemeral are going to be used with increasing frequency, Raine believes, because people are beginning to recognize that the context of a post can be misunderstood, and it is better to have more control over exchanges and not risk the possibility that content stays out there and causes problems down the road.

The content on social media sites is typically assumed to be persistent because most technical systems are architected in ways that prioritize keeping data, notes danah boyd, a senior researcher at Microsoft Research and a research assistant professor in Media, Culture, and Communication at New York University (NYU). They are designed this way in order to enable asynchronous interactions—and also simply because it’s possible, she adds. It wasn’t that long ago that storage was expensive and people were forced to toss data; the fact that we do not have to do so now is often relished, boyd says. Business interests also push designers to focus on persistence because of the possibility of increased traffic and, thus, increased ads, she says.

Yet, people are used to the concept of ephemerality in the real world, and—to a lesser extent—in the early years of the digital world, which was full of hard disk crashes, incompatible and changing document formats, and unreadable floppy disks, maintains Viktor Mayer-Schönberger, a lawyer and professor at the University of Oxford whose research focuses on the role of information in a networked economy. Concurring with Raine, he says, "As users of digital tools discover that the ephemerality they are so used to…is largely gone, they will become wary of the comprehensive digital memory that has replaced it—and look for market-based solutions to reintroduce it. That’s just what this breed of new apps provides."

The apps provide the ability for a user to designate how long a recipient can view the content before it "evapo- rates." While still in a nascent stage, such apps are proving invaluable to consumers and businesses alike.

"Ephemeral messages are incredibly freeing and make people communicate more authentically and freely with their friends," says Jeremy Liew, managing director at Lightspeed Venture Partners, which has invested about $500,000 in Snapchat. The Snapchat app lets users set a duration of between three and 10 seconds in which the receiver can view sent content, before the data disappears. "They can be their real selves…because it’s not there forever."

Apps like Snapchat also raise societal implications about people’s motivations for wanting data to be ephemeral, according to boyd. They "challenge the assumption that persistence is the right default and raises questions about when and where people don’t want persistence," she says. "Given the privacy rhetoric…a persistence-by-default-minded assumption is that anyone who doesn’t want their data to be persistent has something to hide." Yet most users do not see their use of these apps in that light, she says. boyd argues that, more often than not, people turn to data-disappearing apps "because they see no reason to add a particular artifact to their digital detritus because everything is already so cluttered."

A classic case for using Snapchat is when someone takes a picture of something they think a friend will find funny in the moment because of a private joke; they send it off to the friend to make them laugh. However, boyd says, the goal was never for that photo to stick around; it was meant to be an ephemeral act.

"There are users who are trying to keep things secretive, and there are users who are trying to minimize how much data companies have about them," she adds. "But the primary use case is more about challenging the status quo by creating a space for ephemeral media sharing."

In his book Delete: The Virtue of Forgetting in the Digital Age, Mayer-Schönberger says that living in a world where everything shared online is saved forever creates problems for people and societies that need to forget in order to move ahead. When people forget details, they instead abstract and generalize, which keeps us from being "stuck in the past," he says.

"Ephemeral messages are incredibly freeing and make people communicate more authentically and freely with their friends."

"Human forgetting does not only ensure a modicum of real-world privacy, as we forget private details of what we experience over time," he explains. "Human forgetting also helps us to live and act in the present and look toward the future, rather being tethered to an ever-more-comprehensive, but also stifling, memory of our past. A central element of being human is to generalize, to abstract, to see the forest rather than just the trees."

Mayer-Schönberger observes, "Comprehensive digital memory constrains seeing ourselves and each other as evolving over time and changing. We are constantly reminded of who we were, not who we are." He recalls the story of Canadian psychotherapist Andrew Feldmar, who wrote an academic article in 2001 in which he mentioned he had taken LSD in the 1960s. In 2006, while going to meet a friend in Seattle, an immigration officer at the U.S. border Googled Feldmar as part of a random search, and discovered the article. Because Feldmar had not disclosed that he had taken drugs some 40 years earlier—although when confronted he didn’t deny it—he was interrogated for hours and fingerprinted before being barred from entering the U.S., effectively forever. "So his past has come to haunt him—through comprehensive digital memory," says Mayer-Schönberger. "And he was assessed not on who he was, but who he had been 40 years earlier."

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Ephemeral Data in the Enterprise

While ephemeral data apps are gaining popularity with consumers, they are also finding a niche in the enterprise. Less than a year ago, Silent Circle came out with a suite of products for phone, email, text, and video that use end-to-end encryption and erase the session keys from a device once a call or text is ended. The company’s servers do not keep the keys and the encryption keeps the unauthorized from understanding people’s transmissions.

"The goal is to provide secure communications for people who travel who believe their communications are being compromised, and once people have evidence this is going on, there is a need for it," says Jon Callas, Silent Circle cofounder and CTO. He says the company has been gearing the apps more toward businesses because they were surprised by the demand for them from that sector.

For example, there is the Asian law firm that became a client because in the country in which the firm is based, "It is not only legal but part of the cultural milieu that lawyers spy on each other," Callas says. "It’s part of the game; if you can find out something about the other party, then you can use it to your advantage." The firm bought a subscription to Silent Phone, so its employees can make phone calls and feel secure that someone is not eavesdropping. Silent Circle’s apps offer a "burn" feature that lets them set a timer on how long information lasts before it is deleted.

Mayer-Schönberger predicts that if ephemeral apps continue to gain momentum, we will see more of them – not just in the form of innovative apps from startups, but also incorporated into mainstream offerings. "Ephemerality may thus become a market differentiator that gets incorporated into more and more offerings online," he says. "And there are a lot of startups now working on establishing themselves as intermediaries helping people who want to ‘market’ their personal data to data users."

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Is Data Really Ephemeral?

While apps like Snapchat, Gryphn, and Wickr tout the fact that they make data disappear, security experts say that’s a slippery slope. Moxie Marlinspike, a contributor to Open Whisper Systems, which provides open source security for Android mobile devices, and soon for iOS, maintains there is no real way to securely enforce ephemerality.

"It’s fundamentally not possible in terms of how technology works, so all solutions are basically sort of faking it," Marlinspike says. "The data itself is just data, and there’s an app that decides at some point, ‘I’m going to delete this.’ If an app decides to make data disappear, what’s to keep someone else from writing software that says ‘don’t delete it?’" he asks. "There’s no way to securely enforce that, and I think that’s OK in the case of Snapchat, because [it] isn’t really about security; it’s about this fun, ephemeral communication."

Whisper Systems’ technology enables people to communicate privately and securely, he says, which has a different purpose than apps that make data disappear. "Ephemeral data can be so easily circumvented. There are ways to stymie the ephemerality of the communication. But with Snapchat, I’m not sure people are incentivized to do that," Marlinspike says. "With security apps, the consequences of people [intercepting conversations] are generally more severe."

"Ephemeral data isn’t new—what’s new is we have enough compute power and enough storage to record everything."

Liew acknowledges there are always ways for people to capture data. "Even with Snapchat, you can take a screenshot of a picture." In that instance, Snapchat informs the sender that a screenshot was taken. But Liew believes there is an unspoken etiquette among Snapchat users that this would be "considered extremely bad manners." He likens this to the expectation when two people are having a phone conversation that no one is recording it, since that would be a breach of trust. "Yet that’s not the way most texting works—everything is archived forever. Snapchat is trying to get back to that traditional phone conversation model."

Rainie agrees that people often assume things are private and safe, when oftentimes they are not. "Partly that’s a technical story and partly it’s a social story about what people will do when they find out about other people’s secrets." He points out that companies and people with access to companies and people who are friends of people displaying information "can do things that compromise the context in which the picture was originally shared. That’s an artful way of saying there are ways this ephemeral data becomes unstuck."

Liew also notes that Snapchat cannot guarantee impermanence, since there are ways around ephemeral data. For example, someone could use another device to take a photo of the screen. Yet making ephemerality the default does return to older norms of behavior in the same way that people do not expect their telephone calls to be recorded—but it is always possible for someone to do so.

He adds that there is an incorrect perception that Snapchat is primarily used for sexting. He notes that "If people want to send naked pictures, they can do it through any number of mechanisms and have done so via email or texting or via AOL chatrooms or the U.S. Postal Service. I don’t think ephemeral data makes that more or less likely."

Echoing boyd, Callas points out that "Ephemeral data isn’t new—what’s new is we have enough compute power and enough storage to record everything. That’s relatively new in human history…It’s simultaneously intriguing and creepy."

He believes broad social norms surrounding privacy, tolerance, and data will evolve in two directions—that a lot of things that are shocking right now will not be shocking down the road. The sexy photos that someone posted in their twenties will have less impact, Callas claims, because many people will be in similar situations. "It’s going to be common that people have embarrassing pictures, and it’s going to be that things that were embarrassing won’t be embarrassing…because of cultural norms. We will develop a new set of manners and etiquette."

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Further Reading

Albrecht Schmidt and Christian Søndergaard Jensen
Proceedings of the Eleventh international Conference on Database Systems for Advanced Applications. Springer, 2006. Pgs. 141-155 (

"Ephemeral Images, Indelible Data: The Promises and Challenges of Digital Imaging as Applied to Pathology," NCI Biomedical Informatics Blog, Sept. 12, 2012. (

"Courts Weigh in on Accessing Ephemeral Data for E-Discovery," Information Management Journal, Vol. 46, No. 6, November-December 2012. (

boyd, danah.
2010. "Privacy and Publicity in the Context of Big Data." WWW. Raleigh, North Carolina, April 29.

Viktor Mayer-Schönberger
"Delete: The Virtue of Forgetting in the Digital Age." Princeton University Press. July 5, 2011. (

Evgeny Morozov
"The Net Delusion: The Dark Side of Internet Freedom." Reprint edition Feb. 28, 2012 (

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"A Peek Into the Circle"

"Ephemeral Images, Indelible Data: The Promises and Challenges of Digital Imaging as Applied to Pathology."

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