Credentials Inherited by Processes
Processes created or spawned by a principal inherit the principal's credentials. For example, if you log in, are authenticated, and start an application, the application you start inherits your authenticated credentials and runs as though it were you. The application's permissions for any given object are the same as your permissions. Processes spawned by the application carry your identity and pass it down to processes they start.
Note: Changing the setuid permission bit changes only the local operating system identity under which an executable file runs, not the network identity.
Some servers are written to run as separate authenticated principals. For these servers, the system administrator creates an account in the registry database. After you start these servers, the server process authenticates with the registry, receives its credentials, and runs under its own identity, not yours.