Subject: RE: [ers-02.txt] Questions

From: "HOUSSIER Loic RD-MAPS-ISS" <[email-masked]>
Date: Fri, 29 Apr 2005 13:12:36 +0200

Aleksej,

Well, it's more clear to me now...
ERS just proposes a syntax for EV that can be used by CSM to kepp electronic signature valid.
But according to RFC-3126, ES-A is a format that reech the same target than ERS in CMS.

So my question is, if i want to archive signature, i have the choice between RFC3126 ES-A or ERS in CMS. Am I right ?

If I am, will ES-A be obsoleted by ERS in CSM (as shown in Appendix A in [ers-02])  ?

But be sure that I understand ERS is more than just a way to maintain a singature valid.

Regards,

Loïc 

> -----Message d'origine-----
> De : A. Jerman Blazic [mailto:[email-masked]] 
> Envoyé : vendredi 29 avril 2005 11:48
> À : HOUSSIER Loic RD-MAPS-ISS; [email-masked]
> Objet : RE: [ers-02.txt] Questions
> 
> Loic
> 
> This is what I didn't state. You have to distinguish the 
> level of the two
> approaches. ERS deals mainly with providing syntax on (time) 
> evidence and
> evidence on integrity of a data, while RFC3126 provides data 
> strucutre for
> long term validity of a digital signatures. In this case RFC 
> can rely on ERS
> for time and integrity evidence of a signature, so it is a 
> more low level
> syntax. Or in other words, if you equip CMS with accredited 
> time, you can
> ged basic ERS structure (of course ERS is more than that: 
> e.g. grouping and
> hash trees). This is why I said the approaches of LTANS vs. XAdES are
> somehow different, while addressing similar problems.
> 
> BR
> 
> Aleksej
> 
> > -----Original Message-----
> > From: HOUSSIER Loic RD-MAPS-ISS 
> > [mailto:[email-masked]] 
> > Sent: 29. april 2005 11:24
> > To: A. Jerman Blazic; [email-masked]
> > Subject: RE: [ers-02.txt] Questions
> > 
> > Aleksej,
> > Thanks for your reply.
> > 
> > So, to demonstrate the existantce and stability of signature 
> > on particular, there will be two ways in PKIX community:
> > One using rfc3126, one with ERS attribute within a CMS 
> > signature object. Am I wrong ?
> > 
> > Loïc 
> > 
> >  
> > 
> > > -----Message d'origine-----
> > > De : A. Jerman Blazic [mailto:[email-masked]] Envoyé : 
> > vendredi 29 
> > > avril 2005 11:08 À : HOUSSIER Loic RD-MAPS-ISS; 
> [email-masked] 
> > > Objet : RE: [ers-02.txt] Questions
> > > 
> > > Dear Loic
> > > 
> > > I would be very careful here. XAdES for example is like the 
> > name says:
> > > syntax for extended signature, which builds on top of a 
> > signature and 
> > > includes all needed complementary data to provide long term 
> > stability 
> > > of digital signatures. The LTANS position, as I understand it, 
> > > distances from such approach and deals with long term 
> stability of 
> > > data. ERS in this case defines requirements on how to 
> > demonstrate the 
> > > existence and stability of data (not signature on 
> particular) on a 
> > > timeline. It does not define the data structure nor the 
> > syntax and at 
> > > the moment you can freely use any interpretation of an 
> > evidence record 
> > > including CMS. But XAdES? I am not so sure....
> > > 
> > > Best regards
> > > 
> > > Aleksej
> > > 
> > > > -----Original Message-----
> > > > From: [email-masked] 
> > > > [mailto:[email-masked]] On Behalf Of 
> HOUSSIER Loic 
> > > > RD-MAPS-ISS
> > > > Sent: 29. april 2005 10:46
> > > > To: [email-masked]
> > > > Subject: [ers-02.txt] Questions
> > > > 
> > > > 
> > > > Hi all,
> > > > 
> > > > Reading ERS_02, I have question :
> > > > It s said that ER can be part of the Archive or can be 
> stored as 
> > > > another file. What I understand is that we can (using CMS 
> > or XADES) 
> > > > do ER as part of the Archive.
> > > > But Is it compliant with ERS ?
> > > > 
> > > > Thanks
> > > > 
> > > > Loïc
> > > > 
> > > >  
> > > > 
> > > > > -----Message d'origine-----
> > > > > De : [email-masked] 
> > > > > [mailto:[email-masked]] De la part de 
> > > > > [email-masked] Envoyé : vendredi 8 avril 2005 
> > 21:29 À :
> > > > > [email-masked] Cc : [email-masked] Objet : I-D 
> > > > > ACTION:draft-ietf-ltans-ers-02.txt
> > > > > 
> > > > > A New Internet-Draft is available from the on-line
> > > Internet-Drafts
> > > > > directories.
> > > > > This draft is a work item of the Long-Term Archive and
> > > > Notary Services
> > > > > Working Group of the IETF.
> > > > > 
> > > > > 	Title		: Evidence Record Syntax (ERS)
> > > > > 	Author(s)	: R. Brandner, et al.
> > > > > 	Filename	: draft-ietf-ltans-ers-02.txt
> > > > > 	Pages		: 25
> > > > > 	Date		: 2005-4-8
> > > > > 	
> > > > > In many scenarios, users need to be able to ensure and 
> > prove the 
> > > > >    existence and integrity of data, especially digitally
> > > > signed data,
> > > > > in
> > > > >    a common and reproducible way over a long and possibly
> > > > undetermined
> > > > >    period of time.  This document specifies the syntax and
> > > > processing
> > > > > of
> > > > >    an Evidence Record, designed for long-term 
> > non-repudiation of 
> > > > >    existence of data, which particularly can be used for
> > > > conservation
> > > > > of
> > > > >    evidence of digitally signed data.
> > > > > 
> > > > > A URL for this Internet-Draft is:
> > > > > 
> http://www.ietf.org/internet-drafts/draft-ietf-ltans-ers-02.txt
> > > > > 
> > > > > To remove yourself from the I-D Announcement list, send a
> > > > message to
> > > > > [email-masked] with the word unsubscribe in
> > > > the body of
> > > > > the message.
> > > > > You can also visit
> > > > > https://www1.ietf.org/mailman/listinfo/I-D-announce
> > > > > to change your subscription settings.
> > > > > 
> > > > > 
> > > > > Internet-Drafts are also available by anonymous FTP. 
> > > Login with the
> > > > > username "anonymous" and a password of your e-mail 
> > address. After 
> > > > > logging in, type "cd internet-drafts" and then
> > > > > 	"get draft-ietf-ltans-ers-02.txt".
> > > > > 
> > > > > A list of Internet-Drafts directories can be found in 
> > > > > http://www.ietf.org/shadow.html or 
> > > > > ftp://ftp.ietf.org/ietf/1shadow-sites.txt
> > > > > 
> > > > > 
> > > > > Internet-Drafts can also be obtained by e-mail.
> > > > > 
> > > > > Send a message to:
> > > > > 	[email-masked].
> > > > > In the body type:
> > > > > 	"FILE /internet-drafts/draft-ietf-ltans-ers-02.txt".
> > > > > 	
> > > > > NOTE:	The mail server at ietf.org can return the document in
> > > > > 	MIME-encoded form by using the "mpack" utility. 
> >  To use this
> > > > > 	feature, insert the command "ENCODING mime" 
> > before the "FILE"
> > > > > 	command.  To decode the response(s), you will 
> > need "munpack" or
> > > > > 	a MIME-compliant mail reader.  Different MIME-compliant
> > > > mail readers
> > > > > 	exhibit different behavior, especially when dealing with
> > > > > 	"multipart" MIME messages (i.e. documents which 
> > have been split
> > > > > 	up into multiple messages), so check your local 
> > documentation on
> > > > > 	how to manipulate these messages.
> > > > > 		
> > > > > 		
> > > > > Below is the data which will enable a MIME compliant 
> > mail reader 
> > > > > implementation to automatically retrieve the ASCII 
> > version of the 
> > > > > Internet-Draft.
> > > > > 
> > > > 
> > > 
> > > 
> > 
> 
>