Metadata is at the heart of the trust fabric of current R&E Identity Federations. For the trust to properly propagate, this metadata is first collected from and then distributed by the federation towards the federation members. Generally speaking this is the same for both national as well as inter-federations like eduGAIN.

The current models for distributing metadata are strained. The most widely used model that distributes a per federation file with entities suffers from file size issues and comes with a risk on long delays for changes to propagate. The MDQ model is more dynamic and resolves both aforementioned issues, but mandates a centralized service to be available at all time. This is a spof not only technically, but may also be a policy control point.

This activity investigates a new proposal from Leif Johansson, called "push MDQ" which introduces a new, potentially highly scalable way of distributing metadata.