Rory Cellan-Jones

Your photos - stuck in the cloud?

  • Rory Cellan-Jones
  • 21 May 09, 11:12 GMT

The investigation by Cambridge University researchers into what happens - or doesn't happen - when you delete those embarrasing snaps from Facebook and MySpace tells us a couple of interesting things.

Facebook imageThe first is obviously that you're bonkers to put anything online that you don't want a future employer, partner or aged relative to see - because, if the experiment is to be believed, that embarrasing shot of you in fancy dress at a stag night will remain online even after you've deleted it.

The second is that big social networks like Facebook and MySpace are struggling to cope with a difficult dilemma - balancing the costs of running their networks with their users' demands for privacy.

Facebook insists that photos are removed immediately from its own computers when users delete them, but admits that they take longer to disappear from its content delivery network.

When I sounded puzzled about this the PR person pointed me at a Wikipedia page which explains that a content delivery network is "a system of computers networked together across the internet that cooperate transparently to deliver content to end users."

What Facebook, MySpace and other big websites do is use these content delivery networks to store and distribute all those millions of photos and videos which their users want to share. So you may think you are giving your snaps to one computer in California owned by Facebook - but the Cambridge research appears to show that the photos are actually stored on servers maintained by an external company which runs the content delivery network.

Eventually, the deleted photos will disappear from the photo server's cache. Facebook does explain this process in its terms and conditions, as the report from Cambridge points out, telling users that the deletion process is "similar to emptying the recycle bin on a computer."

In other words you may have put your pictures in Facebook's bin, but you will still have to wait for the content delivery network to delete them. True, it is quite difficult to find the "deleted" photos - the researchers worked out their location by carefully noting their URLs before deleting them - but your pictures are still out there in the cloud.

In a telling phrase, the Light Blue Touchpaper blog, where the Cambridge researchers outline their experiment, says the strategy adopted by Facebook and other social networks is understandable because "photos are deleted from these types of sites too infrequently to justify the overhead and complexity of removing them from the content delivery network."

In other words, it's all about costs - something the social networks are struggling to control as their user base expands far more rapidly than their revenue. Facebook in particular has been very successful in bringing in new users around the world. The trouble is that every time a user in, say, India uploads a picture, that costs Facebook just as much money in infrastructure costs as a picture uploaded by an American user. Yet the Indian Facebooker is going to bring in even less advertising revenue than his American counterpart.

Social networking is booming around the world - but the business model still looks shaky. What the Cambridge experiment has shown is that networks like Facebook and MySpace have decided that they just can't afford to give users as much privacy as they might like. And that means that entrusting your photos to the cloud can mean relinquishing control of the way you appear online.


  • Comment number 1.

    I never cease to be amazed at what people put online, both written and as pictures. Never mind the content delivery networks having a lag before deletion, what about those who deliberately visit social networking sites to find who knows who and copying pictures to other systems. At the risk of being accused of fanning a conspiracy theory, these sites provide a tailor made database for anyone looking for associations and with the arrival of facial recognition software, even those who are not named in pictures could be identified. 1984 has finally arrived, albeit 25 years late, but with willing participants !

  • Comment number 2.

    This is a classic case of people assuming something works one way, without actually bothering to check if they're right in that assumption, and then getting annoyed when they discover it doesn't infact work how they assumed it did, and somehow the having the audacity to criticize or blame the person "responsible" for it working the way it actually does, for their own laisser-faire attitude in the first place. [/longsentence]

    If you put a photo on facebook in the first place, you should not assume that it will immediately completely cease to be as and when you want it to. Whilst "delete" is an option, people should assume that once online, something is online forever... just because you've deleted it, doesn't mean someone somewhere hasn't right-clicked it and clicked "Save Image As...", and then there's no stopping what they might want to do with it.

    I'm not suggesting everyone should actually READ the Terms and Conditions of every web site they join (I admit, the Ts&Cs on my company's site are approaching 6,000 words) but people shouldn't be surprised when expected to abide by a document to which they did click "I accept".

  • Comment number 3.

    Let's not forget that there are several websites archiving websites, and while the pictures may expire, what you write will be logged indefinitely! Makes me regret the mawkish, immature and foolish things I used to write. Oh, I still do....

  • Comment number 4.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • Comment number 5.

    I know this is silly, but one of the biggest shames of the digital revolution is that outside of top end domestic and professional digital cameras, the modern photo is far worse quality than the old Olympus Trip advertised by David Bailey in the 1970s. And even the old box brownies (despite a tiny lens) was far superior to your top end phone camera.

    It is a pity that the convenience of digital has made people forget all about decent quality.

  • Comment number 6.

    This comment was removed because the moderators found it broke the house rules. Explain.


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