L2GERSync

L2 Global Exit Root synchronization system that manages GER state on L2 chains

Meet L2GERSync: The Local Librarian

L2GERSync is the component responsible for managing Global Exit Root synchronization on the L2 side. It works closely with AggOracle to maintain local GER state, providing efficient access to current and historical Global Exit Root information needed for bridge operations and claim verification.

The Information Management Challenge

Here’s a scenario that illustrates why L2GERSync is crucial: Imagine your chain receives 50 global state updates per day from AggOracle. Each update contains critical information that users need to verify their cross-chain claims.

Without L2GERSync: Every time someone wants to make a claim, your chain would have to dig through contract logs, query external services, or perform expensive on-chain lookups. The user experience would be terrible – claims would take minutes instead of seconds.

With L2GERSync: The moment AggOracle updates your chain’s global state, L2GERSync immediately catalogs this information in an optimized local database. When someone wants to make a claim, the response is instant – all the necessary information is perfectly organized and immediately available.

L2 chains need efficient access to GER state for several critical operations:

1. Claim Verification: Bridge claims must be verified against current Global Exit Root
2. Proof Generation: Merkle proofs require accurate GER state information
3. API Responses: Bridge Service APIs need fast GER data access
4. Historical Queries: Applications need access to historical GER transitions

L2GERSync’s Solution

L2GERSync provides optimized local GER state management:

graph TB
    subgraph "GER Sources"
        AggOracle[AggOracle<br/>GER Injection]
        L2Contract[L2 GER Manager Contract]
        Events[GER Injection Events]
    end

    subgraph "L2GERSync Processing"
        Monitor[Event Monitoring]
        Index[GER Indexing]
        Store[Local Storage]
        Query[Query Interface]
    end

    subgraph "Data Consumers"
        BridgeService[Bridge Service APIs]
        BridgeSync[BridgeSync]
        Applications[External Applications]
    end

    AggOracle --> L2Contract
    L2Contract --> Events
    Events --> Monitor
    Monitor --> Index
    Index --> Store
    Store --> Query

    Query --> BridgeService
    Query --> BridgeSync
    Query --> Applications

    style Monitor fill:#e8f5e8
    style Index fill:#e3f2fd
    style Store fill:#f3e5f5
    style Query fill:#fff3e0

Figure 1: L2GERSync’s role in L2 GER state management

How L2GERSync Works

GER Synchronization Workflow

sequenceDiagram
    participant AO as AggOracle
    participant L2GER as L2 GER Manager
    participant L2S as L2GERSync
    participant API as Bridge Service

    Note over AO,API: GER Update and Indexing Flow
    AO->>L2GER: Inject New GER
    L2GER->>L2GER: Update Contract State
    L2GER->>L2S: GER Injection Event
    L2S->>L2S: Parse Event Data
    L2S->>L2S: Store GER Information
    L2S->>L2S: Update Local Index

    Note over API,L2S: Query and Response
    API->>L2S: Query GER Data
    L2S-->>API: Current GER State

Figure 2: GER synchronization and query workflow

The beauty: This happens automatically. You don’t need to configure which mode to use – L2GERSync examines your contract when it starts up and automatically configures itself for perfect compatibility.