AppLayer
  • Welcome to AppLayer Docs
  • Introducing AppLayer
    • A Primer on Smart Contracts
    • The Problem With EVMs
    • What is AppLayer?
  • How AppLayer works
    • Validators
    • Sentinels
    • Application Chains
    • Bridging
      • AppLayer-to-AppLayer Data Bridging
      • AppLayer-to-AppLayer Token Bridging
      • AppLayer-to-External Bridging (Ethereum, Solana, etc.)
  • Understanding rdPoS
    • Blockchains overview
    • How rdPoS works
    • Validator implementations
    • Slashing
  • BDK implementation
    • The utils folder
    • The contract folder
    • The core folder
    • Transactions and Blocks
    • Database
    • Contract call handling
    • RLP (Recursive-Length Prefix)
    • P2P Overview
    • P2P Encoding
  • Understanding contracts
    • Solidity ABI
    • Internal and external contract calls
    • Setting up the development environment
    • Contract Tester
  • Precompiled contracts
    • Types of pre-compiled contracts
    • Dynamic and Protocol Contracts
    • SafeVariables and commit/revert logic
    • How to code a precompiled contract
    • Creating a Dynamic Contract (Simple)
      • Simple Contract Header
      • Simple Contract Source
      • Deploying and testing
    • Creating a Dynamic Contract (Advanced)
    • Creating a Protocol Contract (Advanced)
  • EVM contracts
    • State management and VM instance creation
    • Seamless C++/EVM integration
    • C++ to other contract calls
    • EVM to other contract calls
    • Executing contract calls via EVMC
    • Calling EVM contracts from C++
    • Calling C++ contracts from EVM
  • Getting started with AppLayer Testnet
  • Join our Community
  • Get in Touch
  • Glossary
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  1. How AppLayer works

Sentinels

How Sentinels work on AppLayer.

Sentinels are similar to Validators, except they cannot create blocks nor act on their own. It is required that both randomly selected Validators and Sentinels send the same data to the requester, otherwise they will be reported to the network as a malicious node. AppLayer Labs and its partners host them to ensure that will not happen.

Sentinels are open for trusted 3rd parties to host and are KYC'd entities with a high level of scrutiny. Eventually as the network and underlying technology matures, Sentinels will be phased out in favor of a fully permissionless system.

Sentinels require 200,000 $APPL tokens as a prerequisite and are only accepted by the network after a whitelisting by AppLayer Labs.

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Last updated 11 months ago