Twitter hasn’t had a good start to 2009, it was hacked via a phishing scam and then there were concerns that your passwords were up for sale and that’s not a good thing; except there may be a silver lining to Twitter’s cloud because it has also reopened the password anti-pattern debate and the use of OAuth as a solution to the problem. Indeed it does now looks like Twitter will be implementing OAuth as a result. W00t!

However, while it is great news that Twitter will be implementing OAuth soon, they haven’t yet and there are plenty of other services that don’t use it, it’s therefore worth pausing for a moment to consider how we’ve got here and what the issues are, because while it will be great — right now — it’s a bit rubbish.

We shouldn’t assume that either Twitter or the developers responsible for the third-party apps (those requesting your credentials) are trying to do anything malicious — far from it — as Chris Messina explains:

The difference between run-of-the-mill phishing and password anti-pattern cases is intent. Most third parties implement the anti-pattern out of necessity, in order to provide an enhanced service. The vast majority don’t do it to be malicious or because they intend to abuse their customers — quite the contrary! However, by accepting and storing customer credentials, these third parties are putting themselves in a potentially untenable situation: servers get hacked, data leaks and sometimes companies — along with their assets — are sold off with untold consequences for the integrity — or safety — of the original customer data.

The folks at Twitter are very aware of the risks associated with their users giving out usernames and passwords. But they also have concerns about the fix:

The downside is that OAuth suffers from many of the frustrating user experience issues and phishing scenarios that OpenID does. The workflow of opening an application, being bounced to your browser, having to login to twitter.com, approving the application, and then bouncing back is going to be lost on many novice users, or used as a means to phish them. Hopefully in time users will be educated, particularly as OAuth becomes the standard way to do API authentication.

Another downside is that OAuth is a hassle for developers. BasicAuth couldn’t be simpler (heck, it’s got “basic” in the name). OAuth requires a new set of tools. Those tools are currently semi-mature, but again, with time I’m confident they’ll improve. In the meantime, OAuth will greatly increase the barrier to entry for the Twitter API, something I’m not thrilled about.

Alex also points out that OAuth isn’t a magic bullet.

It also doesn’t change the fact that someone could sell OAuth tokens, although OAuth makes it easier to revoke credentials for a single application or site, rather than changing your password, which revokes credentials to all applications.

This doesn’t even begin to address the phishing threat that OAuth encourages – its own “anti-pattern”. Anyone confused about this would do well to read Lachlan Hardy’s blog post about this from earlier in 2008: http://log.lachstock.com.au/past/2008/4/1/phishing -fools/.

All these are valid points — and Ben Ward has written an excellent post discussing the UX issues and options associated with OAuth — but it also misses something very important. You can’t store someone’s identity without having a relationship.

Digital identities exist to enable human experiences online and if you store someone’s Identity you have a relationship. So when you force third party apps into collecting usernames, passwords (and any other snippet of someone’s Identity) it forces those users into having a relationship with that company — whether the individual or the company wants it. If you store someones identity you have a relationship with them. 

With technology we tend not to enable trust in the way most people use the term. Trust is based on relationships. In close relationships we make frequent, accurate observations that lead to a better understanding and close relationships, this process however, requires investment and commitment. That said a useful, good relationship provides value for all parties. Jamie Lewis has suggested that there are three types of relationship (on the web):

1. Custodial Identities — identities are directly maintained by an organisation and a person has a direct relationship with the organisation;
2. Contextual Identities — third parties are allowed to use some parts of an identity for certain purposes;
3. Transactional Identities — credentials are passed for a limited time for a specific purpose to a third party.

Of course there are also some parts to identity which are shared and not wholly owned by any one party.

This mirrors how real world identities work. Our banks, employers and governments maintain custodial identities; whereas a pub, validating your age before serving alcohol need only have the yes/no question answered — are you over 18?

Twitter acts as a custodian for part of my online identity and I don’t want third party applications that use the Twitter API to also act as custodians but the lack of OAuth support means that whether I or they like it they have to. They should only have my transactional identity. Forcing them to hold a custodial identity places both parties (me and the service using the Twitter API) at risk and places unnecessary costs on the third party service (whether they realise it or not!).

But, if I’m honest, I don’t really want Twitter to act as Custodian for my Identity either — I would rather they held my Contextual Identity and my OpenID provider provided the Custodial Identity. That way I can pick a provider I trust to provide a secure identity service and then authorise Twitter to use part of my identity for a specific purpose, in this case micro-blogging. Services using the Twitter API then either use a transactional identity or reuse the contextual identity. I can then control my online identity, those organisations that have invested in appropriate security can provide Custodial Identity services and an ecosystem of services can be built on top of that.

UPDATE

Just wanted to correct a couple of mistakes, as pointed out by Chris, below:

1. Twitter was hacked with a dictionary attack against an admin’s account. Not from phishing, and not from a third-party’s database with Twitter credentials.
2. The phishing scam worked because it tricked people into thinking that they received a real email from Twitter.

Neither OpenID nor OAuth would have prevented this (although that not to say Twitter shouldn’t implement OAuth). Sorry about that.