RE: Specification Schema extract

["Moberg, Dale" <Dale_Moberg@stercomm.com>]

Marty Sachs::> Karsten,
> 
> Here are my thoughts on the "reliability levels" extract from the
> specification schema that you sent.
> Covering note:  It seems to me that there is a big difference between
> persistent and non-persistent security, which is spelled out in the
> extract.
> Persistent:  Must be encrypted at the application level 
> and delivered
>    encrypted to the receiving application.  I think that this would be
>    controlled in the Process Specification Document and not 
> in the delivery
>    channel in the CPA.
>    Non-persistent:  Encryption takes place in the transport 
> (e.g. SSL);
>    decryption takes place in the receiving transport and the 
> document is
>    passed in the clear to the receiving application.  I think 
> that this
>    relates to the "need proper definition" notation in "Document Flow
>    security".  If IsSecureTransportRequired is "yes" but 
> persistence is not
>    required, the CPA must specify an encrypting transport.

I agree with what Marty says above but would like to add a point
that explains the "business significance" of the persistent
and nonpersistent distinction. Consider auditing/archiving.
If nonpersistent forms of confidentiality, authentication, non-repudiation
and so on are used, no archival records of signatures, for example, 
may remain to provide evidence, if a dispute were to arise.
Requiring persistent signatures means that such records will
remain for some agreed upon time. That is one major reason why
recommended implementations for nonrepudiation of origin or receipt
tend to use PGP. S/MIME, or now XMLDsig-- these mechanisms lend 
themselves to fairly easy archiving for record keeping purposes.
This is not _just_ a technical issue.