CWA 16385:2012

Typically, a federation of repositories consists of a number of participating Learning Object Repositories. The locations of those repositories and the description of the protocols they support for exposing their learning resources to the federation are maintained and managed at the federation level. This can either be managed: - By tools such as harvesters or federated search engines that connect the repositories to the federation, or - In a separate registry that manages this information for all the repositories on behalf of these tools. These registries are generally not available outside of the individual federation in which they operate. The obvious problem is that this leads to a duplication of effort because repository descriptions must be entered in the registry of each federation where they are a member. As the result, there are difficulties to keep the information up-to-date across all the registry instances in all the federations. For example, if the Open Learn (OU-UK) repository changes the location of their OAI-PMH target, the location should be changed in the registries of ARIADNE, ASPECT, ICOPER, etc.