Longterm Archive and Notary Services LTANS Working Group

1
Long-term Archive and Notary Services (LTANS)
Working Group

• Charter Review

2
Administrivia

• Chairs
• Tobias Gondrom and Carl Wallace
• Security Area Directors
• Russ Housley and Steve Bellovin
• Security Area Advisor
• Russ Housley
• Mailing List
• Discussion ietf-ltans_at_imc.org
• To Subscribe ietf-ltans-request_at_imc.org
• In Body subscribe
• Archive http//www.imc.org/ietf-ltans
• Web site
• http//ltans.edelweb.fr/
• Hosted by Peter Sylvester
• Contains charter, related documents, milestones,
  etc.

3
WG Description

• Overall aim of the WG is to define mechanisms to
  support the ability to prove the existence and
  validity of data over long periods of time
• Made difficult by certificate expiration or
  revocation, cryptographic weakness, etc.
• Problem to be addressed in two parallel efforts
• Data structures, e.g. archive time stamps
• Protocol for interacting with archive service
• Build on and reconcile existing work
• RFC 3029 (DVCS), RFC 3161 (Timestamp protocol),
  RFC 3126 (long-term signature formats), ATS
  (Archive Timestamps Syntax), TAP (trusted archive
  protocol), etc.
• PKIX, XMLDSIG, SMIME
• ArchiSig, OpenEvidence, USMC PK-E

4
Why ?

• Timestamps are not enough
• What happens if used ts-algorithm gets weak ?
• What happens if used Hash-algorithm is no longer
  reliable ?
• What when certificates run out / are no longer
  available ?
• OCSP from trust-center no longer available ?
• ...

5
Lifetime of signed data
Creation
Signing
Storage
Short/long-Term
Resign / generate Trust
Normal storage
Trusted Third Party / Notary individual basis
Mass storage and re-signing without trusted
third party
6
First Steps

• Trusted Archive Protocol (TAP)
• Archive Time-Stamps Syntax (ATS)
• Data Validation and Certificate Server Protocols
  (DVCS)
• RFC 3029 (DVCS),
• RC 3126 (ETSI)

7
Approach

• Define requirements
• Solve problem, find best solution decided on base
  of requirements
• Make solution

8
Timeline

• Archive signed data
• Notary services

9
Working Group Milestones
Standards track Informational Completed
milestones WG formation (10/21) WG meeting
(today)
10
Questions?
11
Long-Term Archive and Notary Services (ltans)

• Tobias Gondrom
• tobias.gondrom_at_ixos.de

12
LTANS WG (ltans-wg)

• Web page charter, current documents
• http//www.ietf.org/html.charters/ltans-charter.ht
  ml
• Mailing List ietf-pkix_at_imc.org
• To Subscribe ietf-ltans-request_at_imc.org, In
  Body subscribe
• Archive http//www.imc.org/ietf-ltans
• Chairs
• Carl Wallace cwallace_at_orionsec.com
• Tobias Gondrom tobias.gondrom_at_ixos.de
• Security Area Directors
• Russ Housley housley_at_vigilsec.com
• Steve Bellovin bellovin_at_acm.org