BA-11 · LESSON 08

Layer comparison

KEY DEFINITIONS

Terms used in this lesson

Oracle: A system that reports outside information, such as a market price, for use by a protocol.
DLC: Discreet Log Contract: a Bitcoin contract whose settlement can depend on an oracle attestation.
UTXO: Unspent transaction output: one discrete chunk of bitcoin that can be used as a transaction input.

Experts compare custody, unilateral exit, data availability, capital efficiency, privacy, and failure recovery rather than relying on labels.

65 min Difficulty 3/5 Not started

VISUAL MODEL

See the whole mechanism before going step by step

Use the diagrams to orient yourself. Then the guided explanation below teaches every part in depth.

4 explanatory views

CONCEPT-SPECIFIC MAP · state machineOne valid action transforms a known stateSelect any state to inspect its exact role.

RELATIONSHIP MAPOrdered mechanism flow

01
BEFOREKnown state
Identify the facts and objects that exist before the action.
02
ACTIONLayer comparison
The Layer comparison lesson isolates the event that proposes a change.
03
RULEDeterministic check
The enforcing rule accepts or rejects the proposed transition.
04
AFTERSuccessor state
Accepted work creates a new state without silently changing the prior facts.
05
FAILUREState unchanged
A failed condition must not produce a partially accepted successor.

Rule shown: A valid transition names the prior state, action, enforcing rule, and successor state.

STAGE 1 OF 5BEFORE: Known state

Identify the facts and objects that exist before the action.

Governing relationship: A valid transition names the prior state, action, enforcing rule, and successor state. Complete path: 1. BEFORE, Known state. Identify the facts and objects that exist before the action. 2. ACTION, Layer comparison. The Layer comparison lesson isolates the event that proposes a change. 3. RULE, Deterministic check. The enforcing rule accepts or rejects the proposed transition. 4. AFTER, Successor state. Accepted work creates a new state without silently changing the prior facts. 5. FAILURE, State unchanged. A failed condition must not produce a partially accepted successor.

1. State transitionWhat exists, what changes, and what results

BEFORE

Compare the lesson's revocable-channel fixture, DLC outcome-table fixture, 3-of-5 federation, and Ark v2 concept model using identical custody, oracle, monitoring, data, capi…

MECHANISM

Name the exact UTXO or bridge custody and the keys or scripts controlling it.

AFTER

The strongest comparison starts from conditional failure exits and versioned evidence, not marketing categories.

Text equivalent: Starting from Compare the lesson's revocable-channel fixture, DLC outcome-table fixture, 3-of-5 federation, and Ark v2 concept model using identical custody, oracle, monitoring, data, capital, privacy, fee, and recovery questions. The mechanism begins when Name the exact UTXO or bridge custody and the keys or scripts controlling it. The resulting lesson is The strongest comparison starts from conditional failure exits and versioned evidence, not marketing categories.

2. Mechanism pathSelect a stage to inspect its job

STAGE 1 OF 5

Identify the locked Bitcoin

Name the exact UTXO or bridge custody and the keys or scripts controlling it.

Complete path: 1. Identify the locked Bitcoin: Name the exact UTXO or bridge custody and the keys or scripts controlling it. 2. Describe normal operation: Map updates, coordinators, routers, signers, oracles, and databases used before settlement. 3. Exercise unilateral exit: Remove every optional collaborator and list the user's required data, transactions, signatures, delays, and fees. 4. Model loss and outage: Test stale state, lost backup, unavailable counterparty, provider censorship, oracle failure, bridge collusion, and fee spikes. 5. Compare like with like: Score the same dimensions and versions. Labels such as Layer 2 or trustless do not replace mechanism-specific evidence.

3. Rule and failure boundaryWhat accepts the result and where it can stop

ACCEPTED PATH

Every system is tested against the same explicit custody, oracle, monitoring, coordinator, retained-data, delay, fee, privacy, capital, and recovery dimensions using version-pinned evidence.

CHANGED CONDITION

A static label cannot survive a failed required input: lost exit data or fee access removes the Ark path, absent monitoring removes the revocable-channel defense, and oracle absence removes intended DLC outcome settlement while leaving only refund.

Important distinction: Systems called Layer 2 share one standard security model. Channels, federations, rollup-like designs, Ark variants, and other systems have different custody, data, exit, and validation assumptions.

Text equivalent: The accepted path is enforced by Every system is tested against the same explicit custody, oracle, monitoring, coordinator, retained-data, delay, fee, privacy, capital, and recovery dimensions using version-pinned evidence. If the required condition changes, A static label cannot survive a failed required input: lost exit data or fee access removes the Ark path, absent monitoring removes the revocable-channel defense, and oracle absence removes intended DLC outcome settlement while leaving only refund.

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Learn the idea

Layer comparison asks which guarantees remain when coordination fails. Custody asks who can move funds. Unilateral exit asks whether one user can reach Bitcoin without permission. Data availability asks what information must be retained. Capital efficiency, privacy, liveness, fee exposure, and recovery describe other independent trade-offs.

GUIDED EXPLANATION1/5 ideas inspected

Identify the locked Bitcoin

Name the exact UTXO or bridge custody and the keys or scripts controlling it.

The worked example follows the explanation

Inspect every idea above to open it.

Important distinction“Systems called Layer 2 share one standard security model.”

Channels, federations, rollup-like designs, Ark variants, and other systems have different custody, data, exit, and validation assumptions.

FINISH LEARNING FIRST

The questions unlock after every required learning activity

Inspect every guided idea, open the worked example, rebuild its mechanism, and complete the deterministic lesson tool. Your progress is saved automatically.