Subject: WG Action: Long-Term Archive and Notary Services (ltans)

From: The IESG <[email-masked]>
Date: Tue, 21 Oct 2003 10:05:12 -0400

A new IETF working group has been formed in the Security Area.  
For additional information, please contact the Area Directors or the WG Chairs.

Long-Term Archive and Notary Services (ltans)
---------------------------------------------

Current Status: Active Working Group

Chair(s):

Carl Wallace <[email-masked]>
T Gondrom <[email-masked]>

Security Area Director(s):

Russell Housley <[email-masked]>
Steven Bellovin <[email-masked]>

Security Area Advisor:

Russell Housley <[email-masked]>

Mailing Lists:

General Discussion: [email-masked]
To Subscribe: [email-masked]
In Body: subscribe
Archive: http://www.imc.org/ietf-ltans

Description of Working Group:

In many scenarios, users need to be able to ensure and prove the 
existence  and validity of data, especially digitally signed data, in a 
common and  reproducible way over a long and possibly undetermined 
period of time. Cryptographic means are useful, but they do not provide 
the whole solution. For example, digital signatures (generated with a 
particular key size) might become weak over time due to improved 
computational capabilities, new cryptanalytic attacks might 'break' a 
digital signature algorithm, public key certificates might be revoked 
or expire, and so on. Complementary methods covering potential 
weaknesses are necessary.

Long-term non-repudiation of digitally signed data is an important 
aspect of PKI-related standards. Standard mechanisms are needed to 
handle routine events, such as expiry of signer's public key 
certificate and expiry of trusted time stamp authority certificate. A 
single timestamp is not sufficient for this purpose. Additionally, the 
reliable preservation of content across change of formats, application 
of electronic notarizations, and subsequent notary services require 
standard solutions.

The objective of the LTANS working group is to define requirements, 
data structures and protocols for the secure usage of the necessary 
archive and notary services. First, the requirements for the long-term 
archive will be collected. Based on that information we will develop a 
protocol to access archive services supplying long-term non-repudiation 
for signed documents and define common data structures and formats. 
Upon completion of the archive-related specifications, we will address 
'notary services' in a similar way. The term 'notary services' is not 
clearly defined. The working group will determine which functions need 
standards, including transformation of documents from one format to 
another without losing the value of evidence, electronic notarization, 
and further verification of legal validity of signed documents. We will 
determine the needs via the requirements paper and act upon the results 
accordingly.

Work done by the IETF Working Groups PKIX, S/MIME and XMLDSIG will be 
used as the basis to define those structures and protocols. For 
example, the Internet-Drafts 'Archive Time-Stamps Syntax (ATS)' and 
'Trusted Archive Protocol (TAP)' and RFC 3029, 'Data Validation and 
Certificate Server Protocols (DVCS)', contain applicable concepts.

Goals and Milestones:

Nov 03 Initial requirements for long-term archive I-D
Dec 03 Revised requirements for long-term archive I-D
Dec 03 Initial data structures for long-term archive I-D
Dec 03 Initial protocol for long-term archive I-D
Feb 04 Last call requirements for long-term archive I-D
Mar 04 Submit requirements for long-term archive to IESG as informational
Mar 04 Revised data structures for long-term archive I-D
Mar 04 Revised protocol for long-term archive I-D
Apr 04 Last call data structures for long-term archive I-D
Apr 04 Last call protocol for long-term archive I-D
May 04 Submit data structures for long-term archive to IESG as proposed standard
May 04 Submit protocol for long-term archive to IESG as proposed standard
Jul 04 Initial requirements for notary services I-D
Sep 04 Revised requirements for notary services I-D
Nov 04 Last call requirements for notary services I-D
Dec 04 Submit requirements for notary services to IESG as proposed standard