Network Working Group                                           J. Linn
Request for Comments: 1511                        Geer Zolot Associates
                                                        September 1993



              Common Authentication Technology Overview


Status of this Memo

  This memo provides information for the Internet community.  It does
  not specify an Internet standard.  Distribution of this memo is
  unlimited.

Overview

  The IETF's Common Authentication Technology (CAT) working group has
  pursued, and continues to pursue, several interrelated activities,
  involving definition of service interfaces as well as protocols.  As
  a goal, it has sought to separate security implementation tasks from
  integration of security data elements into caller protocols, enabling
  those tasks to be partitioned and performed separately by
  implementors with different areas of expertise.  This strategy is
  intended to provide leverage for the IETF community's security-
  oriented resources (by allowing a single security implementation to
  be integrated with, and used by, multiple caller protocols), and to
  allow protocol implementors to focus on the functions that their
  protocols are designed to provide rather than on characteristics of
  particular security mechanisms (by defining an abstract service which
  multiple mechanisms can realize).

  The CAT WG has worked towards agreement on a common service
  interface, (the Generic Security Service Application Program
  Interface, or GSS-API), allowing callers to invoke security
  functions, and also towards agreement on a common security token
  format incorporating means to identify the mechanism type in
  conjunction with which security data elements should be interpreted.
  The GSS-API, comprising a mechanism-independent model for security
  integration, provides authentication services (peer entity
  authentication) to a variety of protocol callers in a manner which
  insulates those callers from the specifics of underlying security
  mechanisms.  With certain underlying mechanisms, per-message
  protection facilities (data origin authentication, data integrity,
  and data confidentiality) can also be provided. This work is
  represented in a pair of RFCs: RFC-1508 (GSS-API) and RFC-1509
  (concrete bindings realizing the GSS-API for the C language).




J. Linn                                                         [Page 1]

RFC 1511                      CAT Overview                September 1993


  Concurrently, the CAT WG has worked on agreements on underlying
  security technologies, and their associated protocols, implementing
  the GSS-API model.  Definitions of two candidate mechanisms are
  currently available as Internet specifications; development of
  additional mechanisms is anticipated.  RFC-1510, a standards-track
  specification, documents the Kerberos Version 5 technology, based on
  secret-key cryptography and contributed by the Massachusetts
  Institute of Technology.  RFC-1507, an experimental specification,
  documents the Distributed Authentication Services technology, based
  on X.509 public-key technology and contributed by Digital Equipment
  Corporation.

References

  [1]  Kaufman, C., "Distributed Authentication Security Service", RFC
       1507, Digital Equipment Corporation, September 1993.

  [2]  Linn, J., "Generic Security Service Application Program
       Interface", RFC 1508, Geer Zolot Associates, September 1993.

  [3]  Wray, J., "Generic Security Service API : C-bindings", RFC 1509,
       Digital Equipment Corporation, September 1993.

  [4]  Kohl, J., and C. Neuman, "The Kerberos Network Authentication
       Service (V5)", Digital Equipment Corporation, USC/Information
       Sciences Institute, September 1993.

Security Considerations

  Security issues are discussed throughout the references.

Author's Address

  John Linn
  Geer Zolot Associates
  One Main St.
  Cambridge, MA  02142  USA

  Phone: +1 617.374.3700
  Email: [email protected]











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