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Common Authentication Technology Next Generation (kitten)

WG Name Common Authentication Technology Next Generation
Acronym kitten
Area Security Area (sec)
State Active
Charter charter-ietf-kitten-08 Approved
Status update Show Changed 2017-11-15
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Personnel Chairs Alexey Melnikov, Benjamin Kaduk
Area Director Paul Wouters
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Charter for Working Group

The purpose of the Common Authentication Technology Next Generation
(Kitten) working group (WG) is to develop extensions/improvements to the
GSS-API and to the Kerberos authentication system, shepherd specific
GSS-API security mechanisms, and provide guidance for any new
SASL-related submissions.

This charter combines the work of the Kerberos WG and the kitten WG
(under the aegis of the kitten WG). In places, it identifies which WG
was previously home for that work.

The working group will develop extensions and/or updates to the GSS-API,
working on specific items regarding credential management, replay cache
avoidance, error reporting, and supporting stateless and/or distributed

The working group will also maintain and improve upon the Kerberos
protocol, working on items regarding internationalization considering
alignment with the precis work, new initial authentication types,
authorization framework/data, replay cache avoidance, cryptography
advances, interop with 3rd party authentication, and identity

In detail, both existing and new work items include:

Existing Working Group Items

SASL Mechanism for OAuth (draft-ietf-kitten-sasl-oauth)
SASL Mechansim for SAML-EC (draft-ietf-kitten-sasl-saml-ec)
GSS-API IANA Registry (draft-ietf-kitten-gssapi-extensions-iana)
KDC Model (draft-ietf-krb-wg-kdc-model)
PKINIT Hash Agility (draft-ietf-krb-wg-pkinit-alg-agility)
Kerberos IANA Registry (draft-ietf-kitten-kerberos-iana-registries)
Initial and Pass Through Authentication in Kerberos 5 (draft-ietf-krb-wg-iakerb)
Unencrypted Portion of Ticket Extensions (draft-ietf-krb-wg-ticket-extensions)

Provide new interfaces for credential management, which include the
initializing credentials
iterating credentials
exporting/importing credentials

Negotiable replay cache avoidance

Define interfaces for better error message reporting.

Specify an option for exporting partially-established security
contexts and possibly a utility function for exporting security
contexts in an encrypted form, as well as a corresponding utility
function to decrypt and import such security context tokens.

Specify one-time password / two-factor authentication needs for SASL
applications. This could be achieved through an explicit new
GSS-API/SASL mechanism (e.g., or if
the consensus is that due to usability reasons, it is preferable
to do OTP/2FA through an higher level protocol
(Kerberos/OpenID/SAML/SAML20EC/EAP?) then prepare a document
explaining the usability problem and provide pointers for

Prepare, review, and advance standards-track and informational
specifications defining new authorization data types for carrying
supplemental information about the client to which a Kerberos
ticket has been issued and/or restrictions on what the ticket can
be used for. To enhance this ongoing authorization data work, a
container format supporting the use cases of draft-ietf-krb-wg-pad
may be standardized.

Prepare a standards-track protocol to solve the use cases addressed
by draft-hotz-kx509-01 including new support for digital

Today Kerberos requires a replay cache to be used in AP exchanges in
almost all cases. Replay caches are quite complex to implement
correctly, particularly in clustered systems. High-performance
replay caches are even more difficult to implement. The WG will
pursue extensions to minimize the need for replay caching,
optimize replay caching, and/or elide the need for replay caching.

Prepare, review, and advance standards-track and informational
specifications defining use of new cryptographic algorithms in the
Kerberos protocol using the RFC3961 framework, on an ongoing
basis. Cryptographic algorithms intended for standards track
status must be of good quality, have broad international support,
and fill a definite need.

Prepare, review, and advance standards-track and informational
specifications of new pre-authentication types for the Kerberos
protocol, on an ongoing basis.

Prepare, review, and advance standards track updates and extensions to
RFC4121, as needed and on an ongoing basis.


Date Milestone Associated documents
Dec 2022 draft-ietf-kitten-sasl-saml-ec to IESG
Nov 2022 Submit "Best practices for password hashing and storage" to IESG draft-ietf-kitten-password-storage
Oct 2022 Submit document on 2-Factor Authentication in SASL to IESG
Apr 2022 Decide on preferred solution(s) for 2-Factor Authentication in SASL draft-ietf-kitten-scram-2fa
Mar 2022 Submit "SPAKE Pre-Authentication" document to IESG draft-ietf-kitten-krb-spake-preauth
Sep 2013 Adopt work on the GSS-API for replay cache avoidance
Aug 2013 draft-ietf-krb-wg-ticket-extensions to IESG
Aug 2013 Adopt work on exporting partially-established GSS-API contexts
Jul 2013 Adopt work on one or more items for GSS-API cred management
Jul 2013 Adopt work on better error reporting in the GSS-API
Jun 2013 draft-ietf-krb-wg-pad to IESG
Jun 2013 draft-ietf-kitten-kerberos-iana-registries to IESG
May 2013 draft-ietf-kitten-gssapi-extensions-iana to IESG

Done milestones

Date Milestone Associated documents
Done Submit "Channel Bindings for TLS 1.3" to IESG draft-ietf-kitten-tls-channel-bindings-for-tls13
Done draft-ietf-krb-wg-pkinit-alg-agility to IESG
Done draft-ietf-krb-wg-cammac to IESG
Done draft-ietf-kitten-sasl-oauth to IESG