OSF DCE Application Development Guide--Core Components

DCE Security Service
12. The client runtime receives and decrypts the response, and returns data to the
application interface through the API.
Figure 23-8. Application Server Responds to Client’s Request
Client Principal
Security runtime
conversation key 4 encrypted with conversation key 4
Application Server
Application
User Interface
API
RPC
Legend:
app_request()
app_request()
svr_response()
svr_response()
svr_response()
If client is authorized for
app request, then perform
operation
svr_response()
The application server and client can continue to use the fourth conversation key
indefinitely for subsequent conversations. If the server receives an application request
after discarding the conversation key, which it may do if it has not heard from client
for some time, then the server challenges the client to learn the key (see Figure 23-7).
If the client’s ticket to the application server expires, it must acquire a new one (see
Figure 23-6), and so on. If the client wishes to talk to a new service, it must acquire a
ticket to that service (see Figure 23-6).
Note: The illustrations in the walkthrough show the authentication protocol in
the context of a datagram-based network communications protocol. In
the case of a connection-oriented protocol, the client sends both the
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