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7.1
The environment for a composite modulus
The environmental clause adds modulus construction and factor custody to the usual domain parameter and trust conditions. The composite setting means the party who built the modulus may hold an advantage, so custody and the domain boundary have to be written down.
- What it asks
- Evidence the domain parameters, the modulus construction, the factor custody and the verifier trust path. Show who is allowed to know the factors and what they could do with them, and record the domain boundary so that a claimant from one domain cannot be accepted in another.
- What the revision does
- The fourth edition will restate these conditions. The public record stops before the new wording. The 2009 wording is therefore superseded at publication.
- Who it binds
- The domain authority, the key management owner and the verifier operator.
- Evidence an auditor samples
- The domain parameter and modulus records (cryptography standard)
- The factor custody record and the permitted uses (key management)
- The domain boundary definition and its enforcement (architecture)
- The test you can run
- Ask what the party holding the factors could do. If the answer is not written down, the trust model is implicit.
- Common failures
- The factors are held by the same team that operates the verifiers.
- The domain boundary exists in a document but not in configuration.
- How to close it
- Write the trust model as a short paragraph with named roles. The composite setting is safe only when the party with the factors is bounded, and the boundary is the evidence. Put the domain parameter and modulus records in the register first, then work down the evidence list until every line has a date.
- Where it sits against the 2009 edition
- The clause exists today as 7.1 in the 2009 edition. The fourth edition replaces it, and the public record stops before the new wording, so the obligation below is the one in force.
For the file, this row closes when the domain parameter and modulus records exists with a date, a named holder and a pointer, and when the test above has been run and recorded. The domain authority, the key management owner and the verifier operator. owns that answer for 7.1.