Dealing with multiple signatures

Although an array of signatures a la JWS is doable it severely complicates canonicalization.
I believe the following approach is more reasonable:

   {
       {
         "@context": "http://example.com/test-multiple-signatures",
         "Now": "2013-08-30T07:56:08+02:00",
         "ID": "lADU_sO067Wlgoo52-9L",
         "STRINGS": ["One","Two","Three"],
         "Signature":
           {
           }
       },
     "Signature":
       {
       }
   }

That is, there wouldn't be multiple signatures signing _exactly_ the same content.
IMO signatures _wrapping_ each other does the same thing (or better) except in theoretic
use-cases like multiple human attesters.  The latter have considerably better solutions
using a server-based system collecting individual attestant's response _separately_.

The scheme above also copes with countersignatures like when you have filled a shopping-
basket with stuff and perform a B2B checkout.  The merchant could sign the shopping-
basket with its "Merchant key" which would transform it into a non-forgable "Quote".
The purchaser could if accepting the quote just put the shopping-basket object in an empty
PO object and counter-sign it with its "Buyer-key".  Signatures can be pretty cool, right :-)

Cheers
Anders

Received on Saturday, 31 August 2013 08:59:59 UTC