BAC-L3-TIA-114Celestia and modular blockchains
Fraud proofs and validity proofs
Two opposite answers to one question: how a verifier knows a state transition is correct without re-executing all of it.
- Level
- L3 — Infrastructure engineer
- Duration
- 4 h
- Maintainer
- Modular Blockchain / Celestia Architect
Learning objectives
- 01Compare the optimistic model with the validity-proof model
- 02Explain the role of the challenge window
- 03Assess each approach's verification cost
Guided lab
Build a fraud proof against a deliberately invalid transition.
Independent lab
Compare latency, cost and assumptions of both approaches in writing for a real use case.
Security angle
The optimistic model assumes at least one honest, available verifier: cost out what that "at least one" assumes.
Assessment
Working fraud proof plus a comparative note.