Unlike service definitions, you can safely copy and stream service references. This is particularly useful when you create service references from the server side and want to stream these references to various clients.
When streaming service references, however, you need to consider whether or not the service reference remains valid in the new location. If you stream a service reference outside of the visibility defined by the service--for example, if you stream a local service reference across a network--the reference becomes invalid. The service definition that a reference corresponds to has no way of detecting inactive or invalid references.