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The DCE Host Daemon

Each DCE host runs a DCE host daemon (dced) to provide remote DCE management services for a host and its servers. The dced provides remote management of DCE-related host and server data, it provides remote control of a host's servers, and it maintains host-specific state for DCE such as the host's login identity. From the server's perspective, dced is a central point where all servers can consistently inform their host about themselves. From the host's perspective, dced gives clients, management applications, and DCE administrators (via dcecp) a focal point from which to find out about (and even control) servers.

The most important feature of the dced is that it provides the endpoint mapper service. This service maintains the host's local endpoint map for local RPC servers and looks up endpoints for RPC clients. An endpoint is the address of a specific instance of a server that is executing in a particular address space on a given host. Each endpoint can be used on a host by only one server at a time. The endpoint map is the system-specific database on each host, in which servers register their endpoints and associated addressing information (information about communication protocols, objects, and so on). A server registers separate endpoints for each of its RPC interfaces and any objects the server offers with the interface.

If a client makes a remote procedure call to a host without providing an endpoint, the dced searches its endpoint map for the endpoint of a compatible server. Upon finding a suitable endpoint, the endpoint mapper service (depending on the protocols used) forwards the call to that endpoint or returns the endpoint to the client's runtime, which sends the call to the server at that endpoint.

Other remote services of dced include host data management, server control, security validation, and key table management. These are described in detail in the OSF DCE Application Development Guide - Core Components.