Wendy commented on Their Capers’ Public Fields:

So, what’s a better key?

I think Pete answered your question in his comment. The problem with SSNs is not their use as keys; it’s their use as authenticators. The ubiquity of SSNs is both what makes them useful as keys and what makes them horrible as authenticators, because so many people know them. Pete’s proposal in his blog of making all SSNs public would make it even more clear how horrible they are as authenticators. Continue reading →