If AUTH_SHORT, the bytes of the response verifier's string encode a short_hand_verf structure. This opaque structure can now be passed to the server instead of the original AUTH_SYS credentials.
The server keeps a cache that maps the shorthand opaque structures to the original credentials of the caller. These structures are passed back by way of an AUTH_SHORT style response verifier. The caller can save network bandwidth and server CPU cycles by using the new credentials.
The server can flush the shorthand opaque structure at any time. If a flush occurs, the remote procedure call message is rejected because of an authentication error. The reason for the failure is AUTH_REJECTEDCRED. At this point, the caller might try the original AUTH_SYS style of credentials, as shown in the following figure.