Pessimistic Proof
Advanced security mechanism that prevents compromised chains from draining funds beyond their deposits
Background¶
Chains Connected to Agglayer¶
Agglayer creates a seamless network that bridges independent blockchain ecosystems into one cohesive experience. By connecting sovereign chains, it enables:
- Unified liquidity pools across chains
- Seamless user experience as if operating on a single chain
- Shared state and network effects between different blockchains
- Enhanced security through its interconnected design
This architecture delivers the best of both worlds - chains maintain their sovereignty while users benefit from a smooth, integrated multi-chain experience with improved capital efficiency and stronger network effects.
Security Challenge¶
While the Unified Bridge provides robust security for cross-chain transactions, Agglayer implements additional protective measures to handle a critical scenario: what happens if a connected L2 becomes compromised?
This multi-layered security approach addresses two key aspects:
- The bridge ensures safe cross-chain transaction flows
- Protection mechanisms safeguard funds on Agglayer even if connected L2s become compromised
The second aspect is secured via Pessimistic Proof.
Overview¶
Agglayer assumes every prover can be unsound. The pessimistic proof guarantees that even if a prover for a chain is unsound, that prover cannot drain more funds than are currently deposited on that chain. In this way, the soundness issue cannot infect the rest of the ecosystem.
Key Benefits: - Containment: Limits damage to individual chain deposits - Ecosystem Protection: Prevents security issues from spreading - Financial Isolation: Creates a “firewall” between chains
What You Can Do¶
- Secure Multi-Chain Assets: Protect funds across interconnected chains
- Isolate Risk: Contain potential security breaches to individual chains
- Enable Safe Interoperability: Allow chains to interact without systemic risk
How It Works¶
The pessimistic proof mechanism implements a safety boundary between chains - it ensures that even if a chain’s prover becomes compromised or unsound, the damage is strictly limited to the funds currently deposited on that specific chain.
Security Model:
- Each chain has a financial “blast radius” limited to its own deposits
- State transitions are cryptographically verified before acceptance
- Mathematical constraints prevent unauthorized fund drainage
Core Concepts¶
Understand the fundamental architecture and security mechanisms:
Data Structures
Explore Local Balance Trees, Nullifier Trees, and other core data structures.
Learn more →