Abstract: A variety of methods, apparatus, and data structures for managing transient and persistent distributed objects are disclosed. Objects for use as object references are described, both for transient and persistent objects. In one aspect of the invention, a data structure that is intended for use as an object reference for a transient object is disclosed having a set of endpoint addresses, an incarnation number, and an object key. These elements serve to uniquely identify and locate the transient object. In another aspect of the invention, an object that is intended for use as an object reference for a persistent object is disclosed having a host computer name, a locator identification, an object key, and a subobject identifier. The first three elements serve as an indirection to the persistent object and the third element is for use by the persistent object. These data structures enable a distributed object operating environment which integrates both transient and persistent objects.

Abstract: A number of methods and apparatus for managing clients of a computer server. In particular, the usher implements an orderly and predictable server deactivation and/or shut down strategy in generally the following manner. The usher continuously maintains a transaction counter indicative of the number of clients actively utilizing services. For example, the usher may increment the transaction counter when a service is requested and then decrement the transaction counter when a service is completed or terminated. However, at some point in the server operation, the usher may receive a lock up request. This may occur because a client has invoked a deactivation and/or shut down operation, or the server may decide to shut down itself. In any event, upon receiving the lock up request, the usher will not perform any new client requests. Thus the usher controls the accessibility of the server to external clients by preventing new client requests for service in preparation for shut down.