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Shōgen

Attested perception. The piece turns a source's answer into an attested testimony: the exact bytes, their hash, and the transport assumptions the testimony still rests on, named one by one. It carries no price number and no score. A gate-side adapter interprets the bytes, and the testimony's residual rides into the verdict.

In one picture

Shōgen: entry, mechanism and output.ShōgensensorbuiltENTRYA source's answer, as bytesWhat the attestor read, not what itmeansthe canonical name of the sourcethe exact response, when the classkeeps itthe transport's clock, carried as dataMECHANISMRecompute, never interpreta SHA-256 hash over the exact bytesa flag: was the hash recomputed?the named transport assumptions, inorderno truth claim about the contentOUTPUTAn attested testimonya frozen contract with closed keyscarried to the gate in the optionalenvelopeits residual filed into the verdictno number, no scorefrozen contract: AttestedPriceDrawn in the style of its register status: built.
Shōgen attests: what it reads, how it works, what it hands on. The boxes are drawn in the style of the register status; the words come from this page’s data and the contract titles from the frozen schemas.

The gap it fills

In September 2017, the first Chainlink whitepaper named the problem (Steve Ellis, Ari Juels and Sergey Nazarov (2017), Section 4.1, page 11): faults may be correlated across data sources, one feed quietly copying another. It proposed research into “mapping and reporting the independence of data sources in an easily digestible way”. Nine years later, we know of no such map being published: oracle networks aggregate feeds that may share the same upstream, and we know of none that reports the overlap next to its answer.

Two feeds, one origin: source A copies source B, both lead back to one upstream, and an aggregate counts that origin twice.One upstreamwhere the value startsSource Breads the upstreamSource Acopies source B, quietlycopiesAn aggregatecounts two feedsTwo votes,one originan error upstreamreaches bothWhat a diversity certificate writes down, next to the verdict: the shared upstream, the shared host, the shared failure.
Two feeds, one origin, drawn after the whitepaper’s own example: source A copies source B, so an error upstream reaches both, and an aggregate that counts feeds counts it twice. An illustration, no data. The diversity certificate belongs to Shōgen fully developed, not to the piece served today.

Shōgen, fully developed, is an attested perception layer: it captures what each source said over an attested transport, types it into facts, aggregates facts into a quorum verdict, and attaches to that verdict a diversity certificate: the measured independence of the sources behind it, with shared upstreams, shared hosts and shared failures written down. The whole is verifiable offline by a third party with no trust in Shōgen. An attestation proves what a source said, never that the source is right.

What is served today

What is built and served is the attest tool: one committed witness, its bytes, its hash and its named residual hypotheses. The full Shōgen sensor, which produces continuous testimonies across sources, is under test and is not served yet.

The register’s served note for Shōgen: served through the MCP gate: its attested testimony's residual is carried into the verdict, replayed by an integration test.

The served attest tool returns one committed witness, labelled as served: real, notary Shōgen, demonstrative, not probative. Its named residual hypotheses: A(notary-neutrality), A(self-attestation), A(transport-check-delegated). The channel it was recorded over: tlsn-mpc/1.

Contracts

The frozen contracts Shōgen reads or writes, each with the keys it requires, read from the schema files. A contract with closed keys refuses an unknown key instead of ignoring it.

AttestedPrice
schema_version · subject · attestor · residual · transport · utterance · observed_at · octets_recalcules · verifier_revision

What it does not claim

Sources

  • Steve Ellis, Ari Juels and Sergey Nazarov (2017) ChainLink: A Decentralized Oracle Network. Whitepaper v1.0, 4 September 2017. read in part Used for faults correlated across data sources, one source copying another (Sections 4.1 and 5.3), and the research it proposed on mapping the independence of data sources.
  • National Institute of Standards and Technology (2015) Secure Hash Standard (SHS). Federal Information Processing Standards Publication 180-4. read in part Used for the hash every record, line and digest is recomputed with.
  • C. Bormann and P. Hoffman (2020) Concise Binary Object Representation (CBOR). IETF RFC 8949. read in part Used for deterministic canonical bytes.
  • Kaihua Qin, Liyi Zhou, Pablo Gamito, Philipp Jovanovic and Arthur Gervais (2021) An Empirical Study of DeFi Liquidations: Incentives, Risks, and Instabilities. ACM Internet Measurement Conference (IMC). read in part Used for the scale of liquidations and why an attested price matters.

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