LID

From Yadis

LID™ -- Light-Weight Identity™ -- is the original URL-based identity protocol conceived at NetMesh.

LID consists of a growing set of "profiles" (the notion of Yadis services was modeled after LID profiles) for features such as Single-Sign-On, VCard queries, social network queries, authenticated messaging, and others.

More information about LID can be found at lid.netmesh.org.