Summary: Decision-makers can now ship verifiable data streams with production-grade building blocks: W3C Verifiable Credentials 2.0 and Data Integrity for provenance, C2PA for camera- and media-grade authenticity, SCITT and Sigstore for transparency logs, RATS/EAT and confidential computing for runtime attestation, and low-latency market oracles such as Chainlink Data Streams and Pyth pull oracles. This guide distills concrete architectures, pitfalls, and checklists for surveillance, market, and indicative (NAV/iNAV) data.

Verifiable Data Solutions for Surveillance, Market, and Indicative Data Streams

If your product depends on data your users must trust, “verifiable by design” is no longer optional. Since mid‑2025, several standards and platforms have matured from draft to production—W3C Verifiable Credentials 2.0 became a Recommendation, C2PA 2.2 shipped stronger provenance primitives, Sigstore’s Rekor v2 hit GA, and market-data oracles crossed the sub‑second threshold at scale. These enable practical, end‑to‑end verifiability for three stubborn data classes: surveillance video and imagery, high-frequency market data, and indicative portfolio data such as NAV/iNAV. (w3.org)

Below we present reference architectures 7Block Labs deploys, with exact components, latency/security trade-offs, and implementation checklists you can execute in a quarter.

The 2025 trust stack, in four layers

Origin and provenance
- W3C Verifiable Credentials Data Model v2.0 + Data Integrity cryptosuites (EdDSA/ECDSA) for signed, machine-verifiable attestations; JOSE/COSE profiles for JWT/CBOR ecosystems. Ship revocation via Bitstring Status Lists. (w3.org)
- C2PA 2.1/2.2 for content authenticity (still and video), with default Trust List, TSA time-stamps, and improved validation semantics. (c2pa.org)
Runtime attestation
- IETF RATS architecture (RFC 9334): standardized roles (Attester, Verifier, Relying Party) and EAT/JWT/CWT-based results; pair with cloud TEEs (AMD SEV‑SNP, Intel TDX) to prove your ingestion pipeline’s state. (ietf.org)
- Cloud support is mainstream: GA support for Intel TDX and AMD SEV‑SNP on major clouds, with known OS/version caveats and security bulletins to track. (cloud.google.com)
Transparency and audit
- Sigstore Rekor v2 (tile-based logs) for low-ops, append-only transparency; clients available in Go/Python/Java; public instance SLO 99.5%. SCITT (IETF) adds a generalized model for signed-statement transparency, aligning with supply-chain and compliance needs. (blog.sigstore.dev)
Onchain anchoring and low-latency feeds
- Chainlink Data Streams (pull-based, sub‑second pricing, OHLC Candlestick API, State Pricing) and native integrations (e.g., MegaETH) for “just-in-time” onchain validation. Pyth pull oracles (≈400 ms update cadence) with Hermes updates make price freshness app-controlled. (blog.chain.link)

Pattern A — Verifiable surveillance data streams (C2PA + Signed Video + ledger anchoring)

When video or imagery must stand up in court or in public audits, sign at capture and preserve the chain.

Capture authenticity at the edge
- Cameras with on-device signing:
  - Axis Signed Video embeds cryptographic signatures (H.264/H.265 SEI frames) bound to device keys in Edge Vault, yielding self-validating streams. Ensure SEI frames are preserved end-to-end (recording/export). (developer.axis.com)
  - C2PA-compatible cameras (e.g., Sony’s video-capable authenticity) produce provenance metadata verifiable across platforms and, increasingly, social/video sites. (tvtechnology.com)
- Editorial workflows and distribution
  - C2PA 2.2 clarifies validation states (well‑formed/valid/trusted), adds TSA time-stamps in update manifests, and soft-binding recovery for multi-part assets—critical for edited clips and stitched evidence packages. (c2pa.org)
Provenance caveats to engineer for
- Handle certificate revocation and vendor incidents. Example: Nikon’s C2PA certificate revocation in Sept 2025 temporarily invalidated authenticity credentials for affected devices—design your verifier to check revocation lists and to support re‑issuance workflows. (nikonrumors.com)
- Preserve metadata across transcodes and trims: use C2PA-preserving pipelines; for Axis, ensure exporters keep SEI; for C2PA, validate manifest continuity after edits. (developer.axis.com)
Runtime and log integrity
- Attest the ingestion pipeline (NVR/VMS/ETL) using RATS + TEEs, emitting EAT-based attestation results at session start and at fixed intervals. Use SEV‑SNP or TDX instances; track cloud OS/driver caveats (e.g., July 2025 remote attestation limitations on specific guest OS builds). (cloud.google.com)
- Anchor chunk hashes in a transparency log and/or enterprise ledger:
  - Hash each minute of video (per-stream), submit Merkle-leaf to Rekor v2; mirror to SCITT-compatible service for cross-tenant verification. (blog.sigstore.dev)
  - For regulated environments, use Azure Confidential Ledger (price drop in Mar 2025) as a tamper-evident hash registry connected to SQL/Blob digesting. (techcommunity.microsoft.com)
Verification UX
- Provide an offline verifier tool:
  - Validate Axis SEI signatures or C2PA manifests, then fetch Rekor/SPKI proofs to demonstrate immutability at time T, with a TSA chain if applied via C2PA. (developer.axis.com)

Implementation checklist (surveillance)

Devices: enable Signed Video or C2PA capture; rotate device keys annually; export in MKV/MP4 with SEI retained. (developer.axis.com)
Transport: record capture-time UTC, GPS, and device attestations; sign manifests with Ed25519 or P‑256 according to your compliance profile. (spec.c2pa.org)
Ingest: run on SEV‑SNP/TDX nodes; emit EAT JWTs; persist per‑segment SHA‑256. (ietf.org)
Audit: write SHA‑256 to Rekor v2; optionally mirror to Azure Confidential Ledger; export proofs alongside evidence bundles. (blog.sigstore.dev)

Pattern B — Verifiable market data streams (sub‑second, low cost, and market-hour aware)

Latency and integrity are not mutually exclusive anymore; modern oracles and pull models let you verify data with cryptographic attestations while keeping costs under control.

Pull-based low-latency oracles
- Chainlink Data Streams delivers sub‑second U.S. equities/ETFs, FX, and commodities with commit‑and‑reveal, conflict-of‑interest‑free providers, and onchain validation at submission. Q2‑2025 added a Candlestick API (OHLC) and State Pricing for long‑tail and DEX‑centric assets; single low‑latency DONs scaled to ~700 assets in parallel, cutting stream costs >50% YTD. (chain.link)
- Native, real-time integrations:
  - On MegaETH, Data Streams are exposed via a precompile for “just‑in‑time” reads, targeting CEX‑like responsiveness. (theblock.co)
- Pyth pull oracle updates aggregates every ~400 ms on Pythnet; apps fetch latest price updates via Hermes, push onchain, and read with freshness guards; stale reads revert. Solana’s 2024 migration established the pull pattern across chains. (docs.pyth.network)
Market status and schedule signals
- Your protocol should gate behavior on market hours, halts, and LULD events—e.g., via SIP “security/status” messages or exchange feeds—and persist a defensible audit trail of the signals consumed. (nasdaqtrader.com)
Practical patterns we see working
- Perps and options: use Chainlink Streams for mark prices and liquidity-weighted BBO; couple with onchain “reveal+settle” windows of 1–2 blocks on fast L2s or app-chains. (chain.link)
- RFQ/trading UIs: cache Streams or Pyth updates off-chain, verify on submit, and reject if staleness > N ms or if “market offline” flags fire (e.g., after-hours, halts). (chain.link)
- Data ops: keep proof artifacts (report signatures, Merkle proofs, or guardian attestations) with trades for post‑facto disputes.

KPIs to monitor

Median feed-to-finality latency; percentage of orders priced with fresh data (<500 ms).
Staleness rejection rate; halt/SSR compliance (downstream logic matching upstream status messages).
Cost per verified update vs. push cadence equivalents.

Pattern C — Indicative data (NAV/iNAV) and tokenized funds

Indicative values sit between official accounting NAV and intraday trading realities. The key is to make them verifiable and programmable.

What to publish and how often
- Official NAV (EOD): immutable, signed credential (VC 2.0) with JOSE/COSE proofs for downstream reconciliation. (w3.org)
- iNAV (intraday): every ~15 seconds is standard in many markets; providers like ICE produce >4,000 iNAVs across >$7T AUM; Tradeweb operates a real‑time iNAV service used by iShares in Europe. Even though the SEC’s 2019 ETF Rule removed the iNAV requirement in the U.S., iNAV remains widely used for transparency globally. (ice.com)
- SmartNAV/SmartData onchain: publish NAV, AUM, reserves and minting guards to enforce “mint‑only‑if‑reserves” for tokenized funds; this converts back‑office data into onchain servicing rails. (chain.link)
Market-hour awareness for iNAV
- Include schedule fields and market-status gating in the data (e.g., pause iNAV during halts or closed hours). Publish “staleness” and “source market open/closed” flags; this is now standard in low‑latency oracle channels. (chain.link)
Onchain pattern we recommend
- Daily: notarize the official NAV as a VC 2.0 credential signed by the administrator; anchor the hash to Rekor v2 for transparency. (w3.org)
- Intraday: stream iNAV via an oracle channel with commit‑and‑reveal and a strict staleness guard; block mint/redeem if market closed or stale. (chain.link)

Regulatory-grade surveillance and privacy by design

U.S. trade surveillance (CAT) is evolving privacy controls—on Feb 10, 2025, the SEC exempted names/addresses/years‑of‑birth from CAIS, mitigating PII risk while retaining anonymized customer IDs. Build similar minimization into your telemetry and verifiers. (sec.gov)
EU consolidated tape progress (bonds first) requires data contributors to prep connectivity/licensing and not to assume long transition periods—design your aggregation to flex to new CTP operators and schemas. (slaughterandmay.com)

Verifiable web data without server cooperation (TLS proofs)

When you must prove “this page said X at time T” (e.g., terms, prices, statements) without trusting a notary:

TLSNotary (zk/MPC‑TLS) adds a Verifier to a TLS session so you can produce portable, selectively-disclosable proofs of web data origin. Browser and Rust toolchains exist today; TLS 1.2 supported, TLS 1.3 on roadmap. (tlsnotary.org)
Use cases: account ownership proofs, bank statements, or web‑published reference rates feeding off‑chain checks. Pair with a transparency log for time‑anchoring the proof. (tlsnotary.github.io)

Security hardening notes for 2025 deployments

TEEs and attestation
- Track TDX/SEV‑SNP advisories and OS/driver compatibility; some guest OS builds briefly broke remote attestation mid‑2025 on specific clouds. Put attestation checks in health probes and CI. (cloud.google.com)
- SGX users: modern deployments rely on ECDSA/DCAP attestation; EPID attestation service does not cover newer Xeon platforms. (intel.com)
Transparency infrastructure
- Prefer tile-based logs (Rekor v2) for cost/scale; set up independent witnesses/monitors; plan for periodic log sharding and key rotation via TUF-configured roots. (blog.sigstore.dev)
Content authenticity
- Target C2PA 2.1+ for improved trust lists/TSA; ensure video edits preserve provenance; validate manifests end‑to‑end in your CI with c2patool ≥0.19 (2.2 compliance). (c2pa.org)
Market data reliability
- On pull oracles, treat staleness as a first‑class error (Pyth reverts on stale reads). For Streams, enforce per‑block verification and record oracle report IDs with trades. (docs.pyth.network)

Reference architecture diagrams (described)

Surveillance pipeline
1. Camera signs frames (Axis SEI or C2PA) → 2) Ingest on SEV‑SNP/TDX node emitting EAT → 3) Chunk hasher → 4) Rekor v2 + Confidential Ledger anchors → 5) Evidence bundle (video + SEI/C2PA + EAT + transparency proofs). (developer.axis.com)
Market perps engine
1. Streams/Pyth off-chain readers → 2) App checks market-status flags + staleness → 3) Transaction attaches oracle proof → 4) Onchain verify + settle → 5) Archive proof with trade. (chain.link)
Tokenized fund servicing
1. Admin publishes NAV as VC 2.0 → 2) Rekor anchor → 3) iNAV stream every 15s via oracle with market-hour gating → 4) SmartNAV guard rails: mint only if reserves signed and markets open. (w3.org)

30/60/90-day rollout plan

Days 1–30: prove the cryptographic chain
- Pick provenance primitive per stream: Axis Signed Video or C2PA 2.2; for web data, prototype TLSNotary proofs.
- Stand up Rekor v2 and a witness; deploy a minimal RATS verifier; pick your TEE SKU and validate attestation end‑to‑end on your cloud. (developer.axis.com)
Days 31–60: wire market-hour logic and low-latency
- Integrate Chainlink Data Streams or Pyth with staleness/market-status gates and pre‑settlement verification. Capture oracle report IDs with each executed trade. (chain.link)
Days 61–90: compliance and ops hardening
- Add TSA time-stamps for sensitive media; set up daily NAV as VC 2.0 with Rekor anchoring; codify data minimization aligned with CAT privacy direction (no PII beyond what’s necessary). (c2pa.org)

Emerging best practices (copy/paste checklist)

Identity and signatures
- Prefer Ed25519 (small, fast) or P‑256; publish verification keys via controlled identifiers and rotate annually; support revocation via status lists. (w3.org)
Time and clocks
- Log capture-time and attestation-time with monotonic+UTC; if you consume SIP/market messages, record participant vs SIP timestamps for audit. (forum.alpaca.markets)
Freshness policies
- Define per‑asset staleness (e.g., 500 ms for BTC perpetuals on fast L2; 15 s for equity iNAV; “must-be-open” gate for RWA settlement). (chain.link)
Data minimization
- Keep PII out of surveillance telemetry; use hashed IDs/anonymized customer IDs similar to CAT’s CAIS exemption direction. (sec.gov)
Multi-path auditability
- Store hashes in both a public transparency log (Rekor v2) and a private ledger (e.g., Azure Confidential Ledger) to survive vendor or network outages. (blog.sigstore.dev)

What success looks like

Surveillance: You can hand a prosecutor or regulator a single archive containing video, SEI/C2PA manifests, TEE attestation, and Rekor/ACL proofs and they can verify it offline. (developer.axis.com)
Markets: 99% of trades price with sub‑second verified data; halt compliance is automatic; disputes resolve with oracle report IDs and transparency log proofs. (chain.link)
Tokenized funds: NAVs are VC-signed; iNAV streams are flagged with market-hours/staleness; minting is provably constrained by onchain SmartData. (w3.org)

How 7Block Labs can help

Architecture sprints to select your provenance and attestation stack (C2PA vs. Signed Video, RATS profile, Rekor/SCITT layout).
Oracle integration packages (Chainlink Streams, Pyth pull) with staleness/market‑hours gating and dispute tooling.
Tokenized fund servicing: VC‑signed NAV/iNAV pipelines with SmartData guards and audit dashboards.

If you want a short diagnostic: we’ll review one stream (video, market, or NAV) and return a 10‑page gap assessment with a 90‑day remediation roadmap.

References and standards mentioned in this guide (selected)

W3C Verifiable Credentials Data Model v2.0 (Recommendation, May 15, 2025) and related cryptosuites and JOSE/COSE profile. (w3.org)
IETF RATS (RFC 9334) architecture for remote attestation. (ietf.org)
IETF SCITT architecture drafts for signed-statement transparency. (ietf.org)
C2PA 2.1/2.2 technical specifications. (c2pa.org)
Sigstore Rekor v2 GA announcement and docs. (blog.sigstore.dev)
Chainlink Data Streams product docs and Q2‑2025 blog; MegaETH native oracle integration. (chain.link)
Pyth pull oracle docs and Solana migration. (docs.pyth.network)
SEC CAT PII exemption (Feb 10, 2025). (sec.gov)
Axis Signed Video developer docs. (developer.axis.com)
Azure Confidential Ledger pricing/features. (techcommunity.microsoft.com)

Ready to make your data verifiable end‑to‑end? Let’s architect a proof-friendly future for your product.