How do I verify a CA-RA split (a party trusted by the issuer provides the gamma value)

Jun 28, 2013 at 2:45 AM
I am exploring the CA-RA split scenario as mentioned in the source comments.
var thirdPartyikap = CreateOrLoadCertificateAuthority("OTHER: "+ issuerData, GroupType.Subgroup, numberOfAttributes, specification, supportDevice);
   var thirdPartyGamma = ProtocolHelper.ComputeIssuanceInput(thirdPartyikap.IssuerParameters, attributes, tokenInformation, null);
How would I verify the token in this scenario? What is the benefit of this solution?
Jul 16, 2013 at 12:11 AM
The fact that a U-Prove token was issued using the attribute values or a precomputed gamma value doesn't change how it is validated by a Verifier. Precomputed gamma values are useful to 1) remove the need for the Issuer to see the attribute values, or 2) cache the value for renewing a batch of tokens (saving "numberOfAttributes" + 1 modular exponentiations and therefore improving issuance performance).