Machine tagging relationships

I’ve been doing quite a bit of thinking about how to represent relationships in portable contact lists. Many of my concerns stem from two basic problems:

  1. Relationships in one context don’t necessarily translate directly into new contexts. When we talk about making relationships “portable”, we can’t forget that a friend on one system isn’t necessarily the same kind of friend on another system (if at all) even if the other context uses the same label.
  2. The semantics of a relationship should not form the basis for globally setting permissions. That is, just because someone is marked (perhaps accurately) as a family member does not always mean that that individual should be granted elevated permissions just because they’re “family”. While this approach works for Flickr, where how you classify a relationship (Contact, Friend, Family) determines what that contact can (or can’t) see, semantics alone shouldn’t determine how permissions are assigned.

Now, stepping back, it’s worth pointing out that I’m going on a basic presumption here that moving relationships from one site to another is valuable and beneficial. I also presume that the more convenient it is to find or connect with people who I already know (or have established acquaintance with) on a site will lead me to explore and discover that site’s actual features faster, rather than getting bogged down in finding, inviting and adding friends, which in and of itself has no marginal utility.

Beyond just bringing my friends with me is the opportunity to leverage the categorization I’ve done elsewhere, but that’s where existing formats like and FOAF appear to fall short. On the one hand, we have overlapping terms for relationships that might not mean the same thing in different places, and on the other, we have unique relationship descriptions that might not apply elsewhere (e.g. fellow travelers on Dopplr). This was one of the reasons why I proposed focusing on the “contact” and “me” relationships in XFN (I mean really, what can you actually do if you know that a particular contact is a “muse” or “kin”?). Still, if metadata about a relationship exists, we shouldn’t just discard it, so how then might we express it?

Well, to keep the solution as simple and generalizable as possible, we’d see that the kinds of relationships and the semantics which we use to describe relationships can be reduced to tags. Given a context, it’s fair to infer that other relationships of the same class in the same context are equivalent. So, if I mark two people as “friends” on Flickr, they are equally “Flickr friends”. Likewise on Twitter, all people who I follow are equally “followed”. Now, take the link-rel approach from HTML, and we have a shorthand attribute (“rel”) that we can use to create a that follows the standard namespace:predicate=value format, like so:


Imagine being able to pass your relationships between sites as a series of machine tagged URLs, where you can now say “I want to share this content with all my [contacts|friends|family members] from [Flickr]” or “Share all my restaurant reviews from this trip with my [fellow travelers] from [Dopplr|TripIt].” By machine tagging relationships, not only do we maintain the fidelity of the relationship with context, but we inherit a means of querying against this dataset in a way that maps to the origin of the relationship.

Furthermore, this would enable sites to use relationship classification models from other sites. For example, a site like Pownce could use the “Twitter model” of followers and followed; SmugMug could use Flickr’s model of contacts, friends and family; Basecamp could use Plaxo’s model of business, friend and family.

Dumping this data into a JSON-based format like would also be straight-forward:

  "uid": "plaxo-12345",
  "fn": "Joseph Smarr",
  "url": [
    { "value": "", "type": "home" },
    { "value": "", "type": "blog" },
  "category": [ 
    { "value": "favorite" },
    { "value": "plaxo employee" }, 
    { "value": "xfn:rel=met" },
    { "value": "xfn:rel=friend" },
    { "value": "xfn:rel=colleague" },
    { "value": "flickr:rel=friend" },
    { "value": "dopplr:rel=fellow-traveler" },
    { "value": "twitter:rel=follower" } 
  "created": "2008-05-24T12:00:00Z",
  "modified": "2008-05-25T12:34:56Z"

I’m curious to know whether this approach would be useful, or what other possibilities might result from having this kind of data. I like it because it’s simple, it uses a prior convention (most widely supported on Flickr and Upcoming), it maintains original context and semantics. It also means that, rather than having to list every account for a contact as a serialized list with associated rel-values, we’re only dealing in highly portable tags.

I’m thinking that this would be very useful for DiSo, and when importing friends from remote sites, we’ll be sure to index this kind of information.