Identity correlation

From LID Wiki

Identity correlation means that two parties can determine that they have interacted with the same user without requiring the consent of that user. For example, if I show my driver's license at car rental company, and later at a liquor store, the car rental company and the liquor store only need to compare the serial number of my driver's license to be able to correlate that it was me who interacted with both.

Avoiding identity correlation generally involves handing out unique identifiers to different parties: in the above example, the two businesses could not correlate me via the driver's license number if I had shown my driver's license to one of them, and my passport to another. (Although they might be able to correlate me through other information such as my picture, or address.)

To avoid identity correlation in a LID context, users are encouraged to use different LID URLs to interact with the parties that they do not wish to correlate them, and keep the fact that they are using several confidential.