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Public-Key Infrastructure (X.509)

Document Charter Public-Key Infrastructure (X.509) WG (pkix)
Title Public-Key Infrastructure (X.509)
Last updated 1995-10-26
State Approved
WG State Concluded
IESG Responsible AD Sean Turner
Charter edit AD (None)
Send notices to (None)


The PKIX Working Group was established in the fall of 1995 with the
goal of developing Internet standards to support X.509-based Public
Key Infrastructures (PKIs). Initially PKIX pursued this goal by
profiling X.509 standards developed by the CCITT (later the ITU-T).
Later, PKIX initiated the development of standards that are not
profiles of ITU-T work, but rather are independent initiatives
designed to address X.509-based PKI needs in the Internet. Over time
this latter category of work has become the major focus of PKIX work,
i.e., most PKIX-generated RFCs are no longer profiles of ITU-T X.509

PKIX has produced a number of standards track and informational RFCs.
RFC 3280 (Certificate and CRL Profile), and RCF 3281 (Attribute
Certificate Profile) are recent examples of standards track RFCs that
profile ITU-T documents. RFC 2560 (Online Certificate Status
Profile), RFC 3779 (IP Address and AS Number Extensions), and RFC
3161 (Time Stamp Authority) are examples of standards track RFCs that
are IETF-initiated. RFC 4055 (RSA) and RFC 3874 (SHA2) are examples
of informational RFCs that describe how to use public key and hash
algorithms in PKIs.

PKIX Work Plan

PKIX will continue to track the evolution of ITU-T X.509 documents,
and will maintain compatibility between these documents and IETF PKI
standards, since the profiling of X.509 standards for use in the
Internet remains an important topic for the working group.

PKIX does not endorse the use of specific cryptographic algorithms
with its protocols. However, PKIX does publish standards track RFCs
that describe how to identify algorithms and represent associated
parameters in these protocols, and how to use these algorithms with
these protocols. We anticipate efforts in this arena will continue to
be required over time.

PKIX will pursue new work items in the PKI arena if working group
members express sufficient interest, and if approved by the cognizant
Security Area director. For example, certificate validation under X.
509 and PKIX standards calls for a relying party to use a trust
anchor as the start of a certificate path. Neither X.509 nor extant
PKIX standards define protocols for the management of trust anchors.
Existing mechanisms for managing trust anchors, e.g., in browsers,
are limited in functionality and non-standard. There is considerable
interest in the PKI community to define a standard model for trust
anchor management, and standard protocols to allow remote management.
Thus a future work item for PKIX is the definition of such protocols
and associated data models.