+h2. Groups
+
+In order for a user to see (and be able to share with) other users, the admin needs to create a "can_read" permission link from the user to either the "All users" group, or another group that grants visibility to a subset of users.
+
+In a peer federation, this means that for a user that has joined a second cluster, that user needs to be added to the "All users" group on the second cluster as well, to be able to share with other users.
+
+In a LoginCluster federation, all visibility of users to share with other users is set by the LoginCluster. It is not necessary to add users to "All users" on the other clusters.
+
+h3. Trusted clients
+
+When a cluster is configured to use a LoginCluster, the login flow goes to the LoginCluster to log in and issue a token, then returns the user to the starting workbench. In this case, you want to configure the LoginCluster to "trust" the workbench instances associated with the other clusters.
+
+<pre>
+Clusters:
+ clsr1:
+ Login:
+ TrustedClients:
+ "https://workbench.cluster2.example": {}
+ "https://workbench2.cluster2.example": {}
+ "https://workbench.cluster3.example": {}
+ "https://workbench2.cluster3.example": {}
+</pre>
+