BLK 03Technology · 🔵 technical · ≈4 h · 6 lessons + worksheet

Enterprise & permissioned chains

When the participants are known, regulated companies, you don't need mining — you need identity, privacy between competitors, and governance that survives budget season. Meet Fabric, Corda, and Besu: the platforms that carried nearly every insurance consortium.

LO4 · compare platforms & justify a selection

L1Why permissioned exists

Public chains solve trust among strangers with expensive consensus and total transparency. An insurance consortium has the opposite profile: members are identified and contracted, but they're competitors — they want shared workflows with selective visibility.

NeedPublic chain answerPermissioned answer
Who can join / write?Anyone with gasIdentified members via certificates (MSP) / network operator
Who sees my data?Everyone, foreverOnly counterparties (channels, private state, need-to-know)
Finality & throughputMinutes-ish · ~15–100 TPS L1Instant BFT finality · 1,000s TPS (Fabric benchmarks ~3,500)
CompliancePseudonymous — bolt KYC on topIdentity-first by construction
Who pays / governs?Fee market, open governanceThe consortium — which is exactly where B3i and we.trade died

L2Hyperledger Fabric — channels & endorsements

Fabric (Linux Foundation) is a modular consortium platform. Its two signature ideas:

Insurer Apeerledger+ccCA / MSPidentity Insurer Bpeerledger+ccCA / MSPidentity Reinsurer Rpeerledger+ccCA / MSPidentity Ordering serviceRaft — sequences blocks channel: motor-claims (A ↔ B) channel: treaty-cessions (A ↔ B ↔ R) — separate ledger, separate visibility Endorsement flow: client app → sends proposal to required peers (e.g. "A AND R must sign") → each simulates chaincode & signs → orderer sequences → peers validate signatures against the endorsement policy → commit. Policy-as-code for "who must agree before a claim state changes".
Fig 3.1 Fabric: identity per org (MSP), channels giving each business relationship its own ledger, and endorsement policies defining who must co-sign a write.

L3R3 Corda — point-to-point by design

Corda drops the "global broadcast" idea entirely: there is no global ledger. Data moves only between transaction parties via flows; a notary cluster merely attests uniqueness (no double-spend) without seeing full contents. States are UTXO-like immutable facts ("Policy #123 v3") consumed and reissued.

L4Besu / Quorum — the EVM, permissioned

Third path: keep Ethereum's tooling (Solidity, wallets, the entire M02 skill set) but run it as a permissioned network with IBFT consensus and optional private transactions. Hyperledger Besu is the leading client; JPMorgan's Quorum pioneered the pattern and powered early JPM Coin. Sweet spot: consortiums that want EVM talent portability and a future bridge to public L2s (exactly the Kinexys→Base trajectory in Module 09).

L5Choosing — comparison + live worksheet

FabricCordaBesu (perm. EVM)Public L2
Privacy modelChannels + private collections (explicit design)Point-to-point by default (strongest)Privacy groups (Tessera) — added onPublic (zk tricks emerging)
Contract languageGo / JS / JavaKotlin / JavaSoliditySolidity
FinalityInstant (Raft/BFT)Instant (notary)Instant (IBFT)Seconds + L1 settlement
Throughput~3,500 TPS benchmarkedHigh, per-flow~1,000s TPS100s–1,000s
Ecosystem/talentEnterprise Java/Go shopsBanking-centricHuge (EVM)Huge (EVM)
Insurance track recordopenIDL, IBM samplesInsurwave, B3i, bondsBanking rails (Quorum lineage)Etherisc, Arbol, Lemonade
Watch out forOps complexity (CAs, channels)Smaller talent pool, R3 dependencyPrivacy add-ons maturityData publicity, gas UX

Worksheet 3.1 · Score your own use case

interactive

Rate how much each factor matters for your scenario (0 = irrelevant, 3 = critical). The totals re-weight live. Defaults describe a 5-insurer motor-claims consortium.

Factor (weight 0–3)WeightFabricCordaBesuPublic L2
Competitor-grade privacy3320
EVM/Solidity talent reuse2233
Fine-grained approval policies (who must sign)3221
Regulated-finance track record2321
Reach retail customers / public composability1123
Minimal consortium ops burden1123
Weighted total

No single winner exists — the exercise is noticing which weights flip the answer. Present those weights, not the tool, to your steering committee.

L6Consortium governance — where projects actually die

The four rings

What must be governed

Money — who funds build & run, forever? Operations — who runs nodes, upgrades, incidents? Data — who owns records, who may join/leave with what? Legal — is a chain record contractually binding? Which regulator has questions?

Memento mori

How B3i died (2022)

Twenty-plus insurers, working software on Corda, a live Cat XoL product — and insolvency anyway, when a funding round failed. Technology adequate; the money ring broke. Every consortium pitch you ever review should be tested against this case first (full autopsy in M08).

◐ Galileo lens

Galileo skipped consortium governance entirely by being single-operator — one company, three nodes, no committees. That's why it shipped in production while consortia stalled… and also why it earns none of the multi-party benefits. The capstone asks you to weigh exactly this trade.

Watch

Sources: Hyperledger Fabric docs; R3 Corda docs & 2025 RWA figures (R3); Fabric TPS from published benchmarks; consortium histories per Ledger Insights / GTR reporting (as of Aug 2026).