mark nottingham

RFC5785: Well-Known URIs

Wednesday, 7 April 2010

HTTP Standards Web

One of the nagging theoretical problems in the Web architecture has been finding so-called “site-wide metadata”; i.e., finding something out about a Web site before you access it. We wrestled with this in P3P way back when, and the TAG took it up after that.

The easy solution to this is to define a static “well-known” URL — like /robots.txt. However, having a third party come along and squat on part of every Web site’s URL namespace is less than friendly, and eventually it’ll lead to conflicts.

So, in a less-than-ideal but practical solution, RFC5785 now defines a sandbox for these well-known URIs — /.well-known/, and provides a registry for them to assure that they won’t conflict. Submissions and discussion happen on the mailing list.

Thanks to my co-author Eran for his help (and occasional kicks!), as well as all of those who provided input and reviews. I’m hoping to get a Web interface up soon to help make submissions to the registry a bit easier.