I came across today Mozilla Persona. It’s a Single-Sign-On (SSO) system that is similar to OpenID. While it looks like there is no need for yet-another-SSO, it does have some promising features compared to OpenID and especially OpenID provided by “Big Player” like Google and Facebook (actually Facebook doesn’t provide OpenID by similar working Facebook Connect).
The one main benefit is privacy. The first kind of privacy is related to the provider. In OpenID, the provider knows exactly where you’ve logged in too. For example, if I want to use my Google account as an OpenID to sign into a gardening forum, Google will know that I’ve signed up there and they will get notified every time I sign-in. Persona on the other hand, seems to sidestep this issue. After registering with a Persona provider (Mozilla offers one), the provider gives the user cryptographically signed token which he can present to sites he signs in to. The site can verify the validity of the certificate without telling the provider which user it wishes to validate.
Another aspect of privacy provided by Persona is our ease of creating alter-egos (and thus keep our anonymity on the net). Facebook and other OpenID like providers require extensive personal information and has real-name policy (which in case of violation can result in blocked account). Persona, by allowing you to register with any email address (think about Mailinator) it allows you to create these anonymous-persona. It also allows you more control on the kind of profile information it shares with providers.
There is last remaining issue, which still concerns me. If you use an OpenID provider, such as Google, and it decides to block your account then you lose access to all those places you authenticated to using that account. This can be worked around by setting up your own OpenID provider, but that’s not simple. I’m bot sure if Persona offers an easier way around it.
Overall, Persona looks very promising as an alternative to OpenID. If anyone has real experience with it, I would love to hear.