PerMsgToken ::=
          -- as emitted by GSS_Sign and processed by GSS_Verify
                  innerMsgToken ANY

          SealedMessage ::=
          -- as emitted by GSS_Seal and processed by GSS_Unseal
          -- includes internal, mechanism-defined indicator
          -- of whether or not encrypted
                  sealedUserData ANY

          END

APPENDIX  C

MECHANISM DESIGN CONSTRAINTS

   The following constraints on GSS-API mechanism designs are adopted in
   response to observed caller protocol requirements, and adherence
   thereto is anticipated in subsequent descriptions of GSS-API
   mechanisms to be documented in standards-track Internet
   specifications.

   Use of the approach defined in Appendix B of this specification,
   applying a mechanism type tag to the InitialContextToken, is
   required.

   It is strongly recommended that mechanisms offering per-message
   protection services also offer at least one of the replay detection
   and sequencing services, as mechanisms offering neither of the latter
   will fail to satisfy recognized requirements of certain candidate
   caller protocols.