CNS L1 to UNS L1: Domain Transfer Guide

This guide covers two options for transferring from CNS Layer 1 to UNS Layer 1. Both options call the safeTransferFrom function, but the second option passes the _data parameter of abi.encode(['bool'], [false]). See Step 3 for details on the safeTransferFrom domain transfer options.

Prerequisites

• Token ID of minted domain on Layer 1 (Ethereum)
• Owner’s wallet address
• abiCoder.encode( ['bool'] , [false] ) = 0x0000000000000000000000000000000000000000000000000000000000000000

Step 1: Verify Contract Info for Each Registry

• Open the CNS Layer 1 Contract page
• Open the UNS Layer 1 Contract page
• Verify that you’ve opened the correct contracts by checking the Contract address (top of the page) and tracker field (right side of page).

For CNS Layer 1

• contract address should be: 0xD1E5b0FF1287aA9f9A268759062E4Ab08b9Dacbe
• token tracker should read: .crypto (UD)

For UNS Layer 1

• contract address should be: 0x049aba7510f45BA5b64ea9E658E342F904DB358D
• token tracker should read: Unstoppable Domains (UD)

Step 2: Verify Domain Ownership on CNS L1

• Retrieve the token ID of the domain you want to transfer.
• On the CNS Layer 1 Contract page, select Contract -> Read Contract -> and scroll down to complete the OwnerOf function.
• Paste the token ID into the ‘ownerOf’ field.
• Select the Query button to check the ownership and confirm the location of the domain.
• Verify the wallet address returned by the OwnerOf query to ensure it is an exact match to your wallet address.

Step 3: Select a safeTransferFrom Option

Before writing the contract, you must select a safeTransferFrom Option. Both of the safeTransferFrom options operate the same way on the backend, so it doesn’t matter which option is selected as long as all parameters are correctly entered.

OPTION 1: safeTransferFrom function with three fields

• Complete the three safeTransferFrom fields: from, to, tokenId.
  • from (address): Enter the owner’s wallet address
  • to (address): Enter the UNS Layer 1 contract address
  • tokenId: Enter the tokenId of the domain you want to rewrite to the UNS registry (i.e., the same tokenID that you verified in Step 2 above)

OPTION 2: safeTransferFrom function with four fields

• Complete the four safeTransferFrom fields: from, to, tokenId, _data.
  • from (address): Enter the owner’s wallet address
  • to (address): Enter the UNS Layer 1 contract address
  • tokenId: Enter the tokenId of the domain you want to rewrite to the UNS registry (i.e., the same tokenID that you verified in Step 2 above)
  • _data: enter the false boolean parameter required for this function, 0x0000000000000000000000000000000000000000000000000000000000000000

Step 4: Rewrite the Domain to UNS L1 Registry

• At the top of the CNS Layer 1 Contract page, select Contract -> Write Contract -> Connect to Web3 to connect your wallet.
• Then, select Contract -> Write Contract -> and scroll down to complete one of the safeTransferFrom options selected from Step 3 .

• Select the Write button to rewrite or transfer the domain to the UNS Layer 1 registry.

• Sign the transaction with your wallet address.
• Click the View your transaction button to verify the transaction, such as status, from, to, and tokens transferred fields.

Step 5: Verify Domain Transfer to UNS L1

• On the UNS Layer 1 Contract page, select Contract -> Read as Proxy -> and scroll down to complete the OwnerOf function.

• Paste the token ID into the ‘ownerOf’ field.
• Select the Query button to check the ownership and confirm the location of the domain.
• Verify the wallet address returned by the OwnerOf query to ensure it is an exact match to your wallet address. If your wallet address is showing, then it means that your domain transferred successfully from CNS Layer 1 over to UNS Layer 1.