Attributes can be binary or string. You can also define new object classes and attributes. It is typically desirable to store only RPC related information in CDS that doesn't change very often. CDS should be used as a rather static replicated distributed namespace rather than as a dynamic distributed database. Storing the location of application servers and their static attributes is what CDS is best suited for.
Junctions provide a single namespace.
They also serve as an entry point from one namespace to another. Using that, a client that knows the interface of the server it wants to talk to can use the resolved part to bind to the server and pass the unresolved part. December 1993 available from the University of Michigan archive . One of their conclusions is that there is no affect on the time to perform an insertion as the database gets larger, unless CDS is in the process of checkpointing the database. See the paper for details.