What are AVSs and how to select them?

5 min readApr 30, 2024

What is AVS?

Actively Validated Service (AVS) refers to any system that requires its own distributed validation semantics for verification, such as sidechains, data availability layers, new virtual machines, keeper networks, oracle networks, bridges, threshold cryptography schemes, and trusted execution environments.Each AVS has its own set of contracts that hold states relevant to the service’s functionality, such as what operators are running the service and how much stake is securing the service.

In short, AVS means safeguarding other decentralized applications (dApps) by renting the economic security offered by restakers’ Liquid Staking Token (LST) and $ETH.

EigenLayer offers Ethereum-level security to middleware (AVS) at low costs. On the supply side, restakers deposit ETH or LST into EigenLayer to provide economic security. On the demand side, AVS developers rent economic security provided by restakers to construct their services. Node operators help AVSs maintain their services by running specified AVS clients. At the very bottom of supply chain, AVS consumers (DApps, Rollups, etc.) pay AVS developers for the services they offer. Besides, AVS consumers may also airdrop native tokens to node operators and restakers.

Dive into AVS

Different roles have different workflows when taking part in AVSs, as shown in the above figure and as listed below:

Restaker

Restake: Restakers deposit assets into the EigenLayer StrategyManager contract.
Choose Node Operator: Restakers choose operators to delegate to. This delegation is handled by the DelegationManager contract.

Node Operator

AVS Registration/Deregistration: To become an EigenLayer operator and participate in AVSs, one must follow the registration or deregistration process with the DelegationManager contract of EigenLayer.
Run specific off-chain AVS client: Node operators run specialized off-chain client software for the AVSs they choose to serve. This software is separate from the core EigenLayer.

AVS Developer

Developed Customized AVS Contracts: Each AVS developer can design and implement their contracts customizable as long as their entry point (canonically called the ServiceManager) implements the interface expected by the EigenLayer.

Why do we need AVS?

Emerging protocols rely on building their validator sets to provide economic security. However, several issues made their protocol unsecured:

Fluctuating Price. A new protocol’s native token price usually fluctuates, leading to fluctuating economic security.
Insufficient Capital. A new protocol may not gather enough capital to secure itself, resulting in insufficient economic security.
Fragmented Trust. Even though a new protocol does not suffer from the above problems, the economic security might still be far from Ethereum’s.

Cost-of-Corruption (CoC) quantifies the cost an adversary must bear to cause a protocol to lose a desired security property. From the above figure, CoC without EigenLayer is $1B, and CoC with EigenLayer is $13B. This means EigenLayer enhances economic security 10x! Besides, restakers can gain additional yield, including AVS fees and potential airdrops, by delegating their assets to safeguard AVSs.

The AVS Landscape

As of April 24, 2024, there are 8 activated AVSs, according to EigenLayer. EigenDA, Oracle, Witness Chain, and AltLayer have emerged at the top of the TVL rankings for now, while many other AVSs are also innovating rapidly and seeking to enter the market in the foreseeable future.

HashKey Cloud currently participates with all of the AVSs：

EigenDA

EigenDA is a data availability solution with 10 MiB/s of write throughput and the lowest cost in its class. The system’s design is inspired by Danksharding, which promises to scale Ethereum’s DA beyond EIP-4844.

Witness Chain

The EigenLayer AVS for DePIN coordination. It is the first physical state consensus protocol that unifies a siloed DePIN economy. Through WitnessChain, a shared economy of integrated physical assets is unlocked, facilitating the exchange of resources like computing power, energy, storage, and beyond. With over 20 DePINs and Rollups in the vibrant ecosystem, WitnessChain ensures their state validation through robust crypto-economic security powered by EigenLayer Operators.

AltLayer

AltLayer MACH is a fast finality AVS for OP Mainnet and Arbitrum One. As an AVS, users can delegate ETH or LSTs to any of the registered operators. The economic collateral deposited to secure MACH is then used to attest to the validity of a given rollup’s state, thereby offering a fast finality layer for rollups. It will offer the following core services to end users on these rollups: fast confirmation for roll-up transactions, crypto-economic security to detect any malicious network participants, and decentralized validation of rollup states.

Omni Network

Omni is an Ethereum-native interoperability protocol that establishes low-latency communications across Ethereum’s rollup ecosystem. Restaking enables Omni to establish a new precedent for secure, performant, and globally compatible interoperability for the future of Ethereum’s modular ecosystem.

Xterio

Xterio is a Web3 game developer and publisher founded by game industry veterans. It aims to create deep, rich gaming experiences driven by player ownership. Xterio creates rich worlds, stories, and characters to create amazing experiences and games.

Brevis

Brevis is a smart ZK coprocessor that empowers smart contracts to read from and utilize the full historical on-chain data from any chain and run customizable computations in a completely trust-free way to power use cases such as data-driven DeFi, zkBridge, ZK identity, and more. Using EigenLayer, Brevis coChain AVS enables new crypto-economics security with the ZK fraud-proof ZK Coprocessor model. With Brevis AVS, developers can build data-driven apps that operate at a significantly lower cost than the pure-ZK model.

Lagrange

Lagrange State Committees are a ZK light client protocol for optimistic rollups designed by combining EigenLayer’s restaked security with Lagrange’s ZK Coprocessor.

eoracle

The modular and programmable Oracle network secured by Ethereum is built with Eigenlayer.

How does HashKey Cloud select AVS?

We have conducted a full safety assessment of current AVSs to provide risk-adjusted incentives for participating users. Due to the lack of information on the rewards and slashing mechanisms, we consider the risks involved low and will conduct a full assessment when the mechanisms are available.

HashKey Cloud’s partnering with AVSs

From the early stages of the AVSs testnet phase, HashKey Cloud has been actively involved, leveraging our extensive expertise and collaborating closely. HashKey Cloud is one of the first node operators to run ETH validators and AVS validation services. We enabled secure and stable node validation service for our partners and the end users. While providing restaking node operator service, we tailored selective AVS strategy to secure the best risk/reward restaking strategy.