2.0 Specification

The 2.0 ElectionGuard specification is a major new release enabling new voting methods and significant improvements in performance and legibility. It includes the following key features:

• The size of the proofs in the election record has been reduced by more than 90% – reducing the size of the full election record by about a factor of 3.
• Computing the proofs takes about 20% less time.
• Placeholder selections have been eliminated entirely.
• Guardians are no longer part of the election record as their partial decryptions and proofs have been administratively combined into single full decryptions and proofs.
• Range proofs are now included to support voting systems like cumulative voting, range voting, STAR-voting, Borda count, and others.
• A new pre-encrypted ballot format is included to support vote-by-mail, central count, and paper-only poll sites.
• Support is now available for instant verification allowing voters to confirm the accuracy of challenge ballots without waiting for the election record to be published.
• New default parameters are used with ln(2) replacing the Euler-Mascheroni constant as the basis for generation of the large prime.
• The data format of hashes has been clearly described to eliminate ambiguities.

1.1 Specification

Update Glossary.md (#287)

Add a brief description of STAR Voting Method.

Co-authored-by: Lee Richardson <github@leerichardson.com>

1.0 Specification

Updates from previous version

• The large prime p and corresponding cofactor r were changed to correctly match the result of the process for the derivation of the prime.
• The equations for generating proofs of ballot correctness have been optimized.
• Auxiliary keys have been eliminated in favor of using the existing keys for both ordinary and exponential ElGamal encryption.
• A more flexible structure of ballot chaining has been introduced to allow for non-linear chaining or no chaining at all.
• Smaller parameters suitable for testing are included.
• The election record of this version should match that of the prior v0.95 and therefore require no verifier changes (with the exception of using the corrected prime).

0.95 Specification

Updates from previous version

• The large prime p and corresponding cofactor r were changed to move the prime p further from 2^4096.
• A section specifically about writing verifiers was added.
• Various small clarifications and corrections were included.

0.85 Specification

• Initial public release of specification for ElectionGuard