BAC-L3-AVAX-114Avalanche
Cross-chain messaging I — foundations
Making two L1s of the same ecosystem talk: what the validators' aggregated signature proves, and what it does not.
- Level
- L3 — Infrastructure engineer
- Duration
- 4 h
- Track
- Avalanche
- Maintainer
- Avalanche Lead Architect
Learning objectives
- 01Explain message verification by aggregated signature
- 02Send a message between two local L1s
- 03Identify this mechanism's trust assumption
Guided lab
Set up message exchange between two local L1s and trace the full path.
Independent lab
Document the system's behaviour when the source validator set changes mid-flight.
Security angle
Trust rests on the sending chain's validator set: a weak set weakens the receiving chain.
Assessment
Demonstrated message exchange with an annotated trust diagram.