Google's IP anonymization fails to anonymize
In telling the world it will anonymize user IPs after only nine months, Google has appeased EU regulators. At least in part. But it looks like Mountain View's new policy is just another example of Google Privacy Theatre.
On Monday evening, when Google deputy counsel Nicole Wong trumpeted the new nine month policy to Silicon Valley's Churchill Club, she said the company was still mulling "the implementation details." But later in the week, the company outlined its plan with a few terse sentences tossed CNet's way.
After nine months, the company has confirmed with The Reg, Google will "change some of the bits" in the user IPs stored in its server logs. But as the plan stands now, it will leave cookie data alone.
This means the missing bits are easily retrieved.
More than a year ago, the company said it would "anonymize" its server logs after eighteen months. And sometime between March and July, it actually put this plan into action. (The company won't get more specific on dates, perhaps because it originally told the world the new policy would arrive in March).
In this case, anonymize meant "change some of the bits in the IP address in the logs as well as change the cookie information." Google now says it erases exactly eight bits from a user's IP, but it has yet to explain what it actually does to the cookie data. Whatever it's doing, it assures regulators that this eighteen month policy is "a significant addition to protecting user privacy."
Google stresses that its new nine month policy is still very much in the works. "I want to clarify that we are still working out the technical details," a company spokeswoman told us. But it looks like Google will erase fewer than eight IP bits under the nine month plan - without touching cookie info.
"After nine months, we will change some of the bits in the IP address in the logs," the company says. "After 18 months we remove the last eight bits in the IP address and change the cookie information...It is difficult to guarantee complete anonymization, but we believe these changes will make it very unlikely users could be identified."
You can debate whether erasing a few bits actually anonymizes an IP address. But as CNet points out, if your cookie data remains intact, restoring the full IP address is trivial. Google may erase some IP bits on your nine-month-old search queries, but those bits will remain intact on your newer queries - and both sets of queries will carry the same cookie info.
Google argues that users can always delete their cookies. "We have focused on IP addresses, because we recognize that users cannot control IP addresses in logs," the company says. "On the other hand, users can control their cookies.
"When a user clears cookies, s/he will effectively break any link between the cleared cookie and our raw IP logs once those logs hit the 9-month anonymization point. Moreover, we are still continuing to focus on ways to help users exert better controls over their cookies."
Of course, most people don't even know what a cookie is. And if you don't clear Google cookies on your own, they expire only if you die or go to prison. ®
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