Endpoint Id values have no relation to Chain Id values. Since LayerZero spans both EVM and non-EVM chains, each Endpoint contract has a unique identifier known as the
endpointId for determining which chain’s endpoint to send to or receive messages from.When using LayerZero V1 contract methods, be sure to use the correct endpointId listed below:-
1xx: refer to mainnet chains -
10xxx: refer to testnet chains
Contract Description
| Contract Name | Description |
|---|---|
| EndpointV1 | The primary entrypoint into LayerZero V1 responsible for managing crosschain communications. It orchestrates message sending and receiving between various smart contract connections. |
| UltraLightNodeV2 | The Ultra Light Node (ULN) message library contract responsible for verifying and validating crosschain messages using oracle and relayer attestations. |
| RelayerV2 | A contract responsible for relaying crosschain messages. The relayer picks up messages from the source chain and delivers them to the destination chain’s endpoint. |
| NonceContract | Tracks message nonces to ensure proper message ordering and prevent replay attacks across chains. |
| SendUln301 | A send message library contract for LayerZero V1 that handles outbound message preparation and validation. |
| ReceiveUln301 | A receive message library contract for LayerZero V1 that handles inbound message verification and delivery. |
Sepolia Testnet Endpoint
The Sepolia testnet endpoint is connected to Ethereum, Arbitrum, and Optimism mainnets only.
| Property | Value |
|---|---|
| EndpointId | 161 |
| Endpoint | 0x7cacBe439EaD55fa1c22790330b12835c6884a91 |
| RelayerV2 | 0x306B9a8953B9462F8b826e6768a93C8EA7454965 |
| ULNV2 | 0x41Bdb4aa4A63a5b2Efc531858d3118392B1A1C3d |
| NonceContract | 0xc097ab8CD7b053326DFe9fB3E3a31a0CCe3B526f |
Checking Default Configs
To see the default configuration for a given pathway (i.e., fromChain A to Chain B), you can use LayerZero Scan’s Default Checker.