Liminal Existence

Simple Addressing for the Web, Part 1

Addressing is important. It’s something that many people have tried to solve.

I’m interested in addressing because it’s an important piece of web-scale messaging, and of the federated social networks that are an emergent property of verified cross-site communication. In order to communicate with someone, you need to be able to route your communications to them.

The URL is the thing. Except when it’s not.

The URL was supposed to become the way that we negotiated identity. We were supposed to have a “home page,” a place on the internet to call our own. It didn’t quite work out that way, and at the same time as Geocities is shutting down, we’re finally facing the need for a strong conception of identity on the web.

It goes without saying these days that everything we do, everything we interact with, has an associated URL. I can give you my blog URL so that you can read my posts, or my calendar URL so that you can invite me to events. However, for the vast majority of users, URLs aren’t a viable option. Fundamentally, it’s a lack of consistency (or, put another way, unbridled diversity) that makes URLs unusable as identity markers. Take the following URLs as a proof-by-example:


All of the above are URLs which I see while interacting with sites on the web. Unlike postal addressing, phone numbers, or email, there’s no consistency. The path part of the domain may as well be line noise in the latter four examples. By association, the pattern used by Flickr, MySpace, and Twitter is a fluke. Beyond that, my username doesn’t match across the three social networking sites, and as such it’s nearly impossible for a friend, relative, or co-worker to guess what my URL is, even given a domain.

I don’t see a way to fix URLs across the web so that we can encourage people to use them as identifiers. OpenID has tried, and the results are nothing short of abysmal.

Back to the Future

If not URLs, what should our new web addressable identities look like? The simplest answer is “like an email address.” They’re universally recognizable. Billions of people have email addresses and know how to use them. All the major IM providers have moved towards email-like addresses as identifiers (gone are the integers of ICQ). Most importantly, email addresses are easy to construct and resolve.

The net result of this line of thought is that instead of @blaine for my Twitter address, I’d be, and on I’d be I could share my Myspace identity as, and on Facebook I could be

The problem is that those addresses conflict with an already-existing namespace, specifically email. Which isn’t surprising, but it is problematic. Can you send me an email at or What happens when you do? Unfortunately, there aren’t clear answers for those questions, and while some social networks might choose to make “Social Network Addresses” work as email addresses, it would be an uphill battle to convince all providers to do so.

Use What’s Already There

I’ve been thinking about this problem a lot lately, and while the approach of re-using email semantics to provide human-readable web addresses/identities is very attractive, the proliferation of addresses (one for each network) and namespace collisions are less than ideal. After having extensive conversations with Alexis Richardson and Tony Garnock-Jones, the general approach for discovery became clear to me, but I didn’t have a more generally applicable form for the addresses themselves.

Eventually, talking over the problem with John Panzer and Breno de Medeiros at Social Web Foo, the solution was there, blazing as bright as the California Sun; Google Profiles means that Google is now providing links to all my social network profiles. They’re also my email provider.

My email address is If you transform that to, you get my profile data, and away we go. Every email provider these days has a website, and Eran’s LRDD, new on the scene, provides a discovery mechanism that everyone (i.e., every mail provider, even if they’re only hosting static content) can implement in just a few minutes.

This is an important, exciting transformation. Now, with one identifier, I can share all the social bits of myself to anyone I please.

Where are my photos?

Where’s my calendar?

What’s my phone number? Look it up with, and I’ll give you permission to see it and store it in your address book.

They’re all the same.

If I want to share a different set of social interactions, say, my work identity, I can give my Osmosoft or BT addresses, and, respectively. Now just photos of conferences come up, and the calendar that you’ll find is my work calendar, not my social calendar.

Talking about this problem with others unearthed a post last year by Brad Fitzpatrick and EAUT, which were both aimed at solving the OpenID problem, but both take the same approach as the one that I outline here. EAUT seems to have been lost in the swamps of XRDS-Simple, and Brad’s post was probably too early to the races, in true Brad style (if you want to know what’s coming to the internet in five years, just read his blog posts).

With a swift and general agreement-in-principle, there’s been some very positive movement towards promoting this concept as a way to bring the power of strong identity that email provides to the web. John has an excellent post on the subject, and it seems like a name for the project has emerged: WebFinger.

Part Two (coming tomorrow) goes in depth about how this all works on the tech side. Bits on the wire, as Tim Bray says.