Feeds

Database anonymity at risk, warns researcher

Prof Ohm resists data safety claims

Top 5 reasons to deploy VMware with Tegile

People might be more identifiable than previously thought from supposedly anonymised information contained in large databases, according to a technology law expert. New research recommends that privacy practices and even privacy laws need to change.

Increasing amounts of personal information are collected by organisations and stored in massive databases. That information is sometimes used or released after being stripped of elements that could identify individuals in a process called 'anonymisation'.

University of Colorado Law School Associate Professor Paul Ohm, though, has said that the techniques used no longer work and that it is now possible to identify people from the release of supposedly anonymised records.

"With the supposed power of anonymisation you can share the data with anyone you want, you can store the data for as long as you like," Ohm told podcast OUT-LAW Radio. "And traditionally it has been a conversation stopper. Once you assert anonymisation everyone nods their heads and says 'that's fine, privacy is protected here, let's focus on something else'."

"But even though you are deleting many of the identifying fields of information, everything you leave behind retains identifying power," he said.

Ohm said that research has shown that a combination of increasingly powerful computers and the prevalence of large databases has made it possible to "re-identify" people whose records have been anonymised.

One researcher in Massachusetts about 15 years ago discovered that 87% of Americans are uniquely identified by three pieces of information: their date of birth, their sex and their zip [post] code," he said. "Now the problem was that until she announced her findings, zip code, birth date and sex were three pieces of information that we presumed were privacy-protecting, were anonymised. So they appeared in all sorts of databases."

Ohm told OUT-LAW Radio that the problem was huge because such trust had been placed in anonymisation that it was enshrined in legislation. "Virtually every privacy law allows you to escape the strictures and requirements of the privacy law completely once you've anonymised your data," he said. "Every policy maker who has ever encountered a privacy law, and that's in every country on earth, will need to re-examine the core assumptions they made when they wrote that law."

Ohm said that the problem was hard to solve because the very pieces of information that identify a person are the pieces which are useful to researchers.

He proposed, though, that in some fields of research, such as health, it would be possible to open up much more data than is currently permitted as long as you controlled access to it.

"We can't trust technology any more but at the same time we don't want to keep this information from researchers. So my solution is that we shift our trust from the technology to the people," he said. "We write down the rules of trust among health researchers... [we say] you can get my data but only on a need to know basis."

The anonymisation research can be seen here.

An interview with Prof Paul Ohm can be heard on OUT-LAW Radio here.

Copyright © 2009, OUT-LAW.com

OUT-LAW.COM is part of international law firm Pinsent Masons.

Choosing a cloud hosting partner with confidence

More from The Register

next story
Preview redux: Microsoft ships new Windows 10 build with 7,000 changes
Latest bleeding-edge bits borrow Action Center from Windows Phone
Google opens Inbox – email for people too thick to handle email
Print this article out and give it to someone tech-y if you get stuck
Microsoft promises Windows 10 will mean two-factor auth for all
Sneak peek at security features Redmond's baking into new OS
FTDI yanks chip-bricking driver from Windows Update, vows to fight on
Next driver to battle fake chips with 'non-invasive' methods
UNIX greybeards threaten Debian fork over systemd plan
'Veteran Unix Admins' fear desktop emphasis is betraying open source
Entity Framework goes 'code first' as Microsoft pulls visual design tool
Visual Studio database diagramming's out the window
Google+ goes TITSUP. But WHO knew? How long? Anyone ... Hello ...
Wobbly Gmail, Contacts, Calendar on the other hand ...
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
New hybrid storage solutions
Tackling data challenges through emerging hybrid storage solutions that enable optimum database performance whilst managing costs and increasingly large data stores.