Say Y or M here to include support for RxRPC session sockets (just the transport part, not the presentation part: (un)marshalling is left to the application). These are used for AFS kernel filesystem and userspace utilities. This module at the moment only supports client operations and is currently incomplete. See Documentation/networking/rxrpc.txt.
Say Y here to make runtime controllable debugging messages appear. See Documentation/networking/rxrpc.txt.
Provide kerberos 4 and AFS kaserver security handling for AF_RXRPC through the use of the key retention service. See Documentation/networking/rxrpc.txt.