LayerZero V2: Explaining DVNs
This article focuses on the verification of messages sent across LayerZero, which is accomplished by entities called Decentralized Verifier Networks (DVNs).
Looking for a complete deep dive into LayerZero V2? Read it here.
You can also listen to a recent Twitter space LayerZero Labs hosted that explains DVNs from the perspective of the teams that run them.
What is a Decentralized Verifier Network (DVN)?
Every application built on LayerZero can Configure a Security Stack comprised of a number of required and optional Decentralized Verifier Networks (DVNs) to check the payloadHash emitted for message integrity, specifying an optional threshold for when a message nonce can be committed as Verified.
In other words, DVNs are the entities responsible for verifying messages sent across chains by applications that use LayerZero.
Who Can Run a DVN?
LayerZero is permissionless.
Therefore, any entity can build a DVN or develop a DVN Adapter as long as its verification schema can confirm the integrity of a message’s payloadHash.
This leads to a wide array of DVN options for application developers to select from, spanning multiple client types, validation methods, validation sets, and proving techniques.
For example, a single DVN may require the participation of 20 validators spread across multiple continents and be run by a crypto-native Ethereum research organization. Another DVN may involve a handful of signers from a curated group of enterprises. More novel DVNs may leverage a re-staking protocol and implement economic security or slashing mechanics.
Over 30 DVNs are currently available to applications building on LayerZero, spanning verification methods that use zk-technology, middlechains, consortium signers, and third-party bridges.
A full list of DVNs available can be found here.
DVNs coming soon include native bridges, more third-party bridges, restaking services, zkOracles, and MPC wallets.
Why are DVNs Important?
Applications built on LayerZero may choose any DVN (or combination of DVNs) to verify messages going between chains. The selected configuration of DVNs is part of an application’s Security Stack.
The LayerZero protocol was deliberately designed to take an unbiased stance on how messages are verified. Rather than enforcing one fixed security approach, LayerZero hands ownership of security over to the applications themselves.
We believe developers should choose the verification methodology that fits their project’s needs and that it can and should evolve over time with research and project growth without any compromise to long term security.
This is a design choice that differs from most messaging protocols and services, which instead offer only a single shared security configuration, continually updating a single, monolithic end-to-end security model (i.e. validator set, oracle, middlechain, etc) to include new chains.
A one-size-fits-all approach to security often leads to applications either under or overpaying for security. For example, an omnichain NFT project has much lower security needs than an omnichain money market. One project secures < 0.5 ETH value transfers, while another may secure $1B+. However, if both are built on a shared security cross-chain protocol, their projects — and user base — pay the same amount for security (shown below).
In contrast, with a diverse and growing set of DVNs, LayerZero developers can configure security parameters to best suit their application rather than being forced to fit their application into a rigid, monolithic architecture. This not only allows for more immediate flexibility, but it also future-proofs applications. For instance, without writing any additional code, an application can swap an optimistic oracle DVN for a battle-tested zkOracle as new technologies become available.
Research and time will introduce safer and more sophisticated methods of securing information delivered between chains. LayerZero V2 enables such advancements to be leveraged in the future.
How are DVNs Used in Practice?
An application’s “Security Stack” refers to its unique configuration of DVNs, Executors, and other security preferences. This includes choices such as enabled chains and the number of block confirmations DVNs must wait for message verification.
For the purpose of this article, we will only focus on the DVN aspect of the Security Stack.
The concept called “X of Y of N” is the core of the Security Stack. It is the configuration of DVNs inside a Security Stack, describing how applications select and/or remove DVNs to verify messages. (Editor’s note: video explanation here.)
X of Y of N allows applications to combine DVNs however they like. Application developers can designate a quorum of DVNs to check the integrity of a cross-chain message before signing off on its validity.
For instance, a “1 of 3 of 5” combination of DVNs would include one required DVN and two arbitrary DVNs out of a total of five to verify a message before moving on to execution.
When building a strong Security Stack, applications should combine DVNs that minimize collusion and/or hack risk. For example, a DVN setup of Google Cloud and the Axelar DVN Adapter is a very hard Security Stack, as it includes verification from a centralized and a decentralized entity, minimizing collusion risk (and more DVNs can be added to this setup later on).
To minimize risk, applications can run their own DVN, reach out to DVN teams to perform due diligence, and/or choose a DVN combination where it is impossible to collude.
Conclusion
V2 is about connecting blockchains, universal development, and application-owned security.
With V2, LayerZero is the antithesis of vendor lock-in, allowing developers to choose, modify, and combine different types of verification methods based on a specific use case.
Eliminate silos. Build everywhere. Own security.
Thank you to Irene for co-writing this article.
Contact
For more information on V2, check out this thread, read this article, or check out our docs. To learn more about LayerZero in general, check out the website. For additional information, the LayerZero Labs team is available to answer general questions on Discord and Telegram. You can also follow LayerZero Labs on X to receive the most up-to-date information.
- For specific DVN inquiries, fill out this form!
About LayerZero
LayerZero is a permissionless, censorship-resistant, and immutable protocol that connects blockchains. Using LayerZero, developers can send and compose arbitrary messages across chains while preserving full control over their application’s security.
