Security Context
The security context is a pair of GASSAPI data structures that contain shared state information, which is required in order that per-message security services may be provided.
The context initiator is authenticated to the responded, and may require that the responder is authenticated in turn.
The initiator may optionally give the responder the right to initiate further security context (delegation).
To establish and maintain the security context, some GSSAPI calls return a token data structure, which is a cryptographically protected opaque data type. The caller is responsible for transferring the token to the peer application, which should then pass it to a corresponding GSSAPI routine which will decode it and extract the information.