Long-Term Archive and Notary Services (ltans)

Last modified: 2011-07-19

Chairs

Security Area Director(s)

Security Area Advisor

Mailing Lists:

General Discussion: ltans@ietf.org
To Subscribe: http://www.ietf.org/mailman/listinfo/ltans
Archive: http://www.ietf.org/mail-archive/web/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

Done Initial requirements for long-term archive I-D
Done Initial data structures for long-term archive I-D
Done Revised requirements for long-term archive I-D
Done Revised data structures for long-term archive I-D
Done Initial requirements for notary services I-D
Done Initial protocol for long-term archive I-D
Done Revised requirements for notary services I-D
Done WG Last call requirements for long-term archive I-D
Done Submit requirements for long-term archive to IESG as informational
Done Submit data structures for long-term archive to IESG as proposed standard
Done WG Last call data structures for long-term archive I-D
Nov 2007 Protocol revisions for long-term archive I-D
Feb 2008 WG Last call protocol for long-term archive I-D
Mar 2008 Submit protocol for long-term archive to IESG as proposed standard
May 2008 Recharter or close the working group

No Internet-Drafts

Request for Comments

Internet SocietyAMSHome - Tools Team - Datatracker - IASA - IAB - RFC Editor - IANA - IRTF - IETF Trust - ISOC - IETF Journal - Store - Contact Us
Secretariat services provided by Association Management Solutions, LLC (AMS).
Please send problem reports to: ietf-action@ietf.org.