Cross Domain Messaging on the Autonomys Network
This guide explains what XDM is and walks you through how to transfer assets between consensus and domain chains.
Introducing Cross Domain Messaging (XDM)
Cross Domain Messaging (XDM) is a core feature of the Autonomys Network that enables secure and seamless communication between independent blockchain domains, such as the consensus chain and specialized domains like Auto EVM. XDM allows these separate blockchains to exchange assets, messages, and data reliably, enhancing interoperability and collaboration across the entire Autonomys ecosystem.
If you want to learn more about the technical nuances of XDM you can find further details in our protocol specs.
XDM Confirmation and Timing
To maintain security, there is a challenge period that has to expire when transferring tokens between domains and the consensus chain. Tokens are not fully available for use until the confirmation time has passed. Study the table below to understand confirmation blocks and rough timings:
| Source | Destination | Confirmation Blocks | Confirmation Time |
|---|---|---|---|
| Consensus | Domain | 100 consensus | ~10 minutes |
| Domain A | Domain B | 14,400 domain | ~1 day |
| Domain | Consensus | 14,400 domain | ~1 day |
Refunds due to a failure to complete an XDM transfer will take 28,800 blocks in total
As long as the XDM is confirmed on the source chain (100 consensus blocks or 14,400 domain blocks) the XDM is able to be relayed and executed (the transfer happens) on the destination chain.
The destination chain generates an XDM response that will be sent back to the source chain after the XDM response is confirmed on the destination chain (100 consensus blocks or 14,400 domain blocks), but the XDM response is mostly a no-op and only useful when the XDM is failed and it is necessary to refund the sender on the sender chain.
XDM Fees
An XDM transfer in any direction costs 2 tAI3 on Taurus. This fee amount is yet to be determined on mainnet and there are plans to make it dynamic. The price is also likely to change based on the outcomes of the SR Labs security audit report.
What Happens to the XDM Fee?
The tAI3 is earned by the operators for processing the transaction. They share that execution fee with their nominators. A portion also goes to farmers for storing the transaction.
Executing XDM Transfers
Consensus to Auto EVM domain
Visit https://astral.autonomys.xyz/taurus/transfer
Select networks for XDM consensus → Auto EVM. Enter amount to transfer.
Hit Send token and you will be asked to approve the signature request.
After hitting Approve you will see an extrinsic hash.
Which you can search on Astral.
Our target account starts with no tokens.
We can also check the balance on the Auto EVM explorer at https://blockscout.taurus.autonomys.xyz/
We wait 10 minutes for the confirmation…
And we have successfully completed an XDM transfer from consensus to Auto EVM.
Auto EVM domain to consensus
So now we have some tokens on the Auto EVM domain, let’s try and send some back the other way.
First, we will need the 0x public key of the account you want to send the tokens to on consensus. If you do not have this, you can get it from ss58.org as per the below screenshot.
Next, you will need to navigate to the Auto EVM domain in PolkadotJS by either selecting it in the network switcher or following this link: Polkadot/Substrate Portal
Working from the top down:
- Select the account you want to XDM from.
- select the
transporter.transfer()extrinsic. - Select
Consensusin thedstLocationchainId. - Enter the
0xaccount address we got above in theAccountId32textbox. NOTE: it is possible to use the “Substrate: 42” address that starts with a5in this box if you find that easier. - Enter the amount. Which will be the number of tokens with 18 zeroes afterwards as the value is in Shannons.
- Submit Transaction.
Remember that there is a 2 tAI3 fee for each XDM transaction and that you will need to wait for 14,400 domain blocks to pass which is about a day before the funds are available in the destination account.
We are working on an update for EVM wallet detection in Astral that will enable you to XDM back to consensus without needing to use PolkadotJS and instead stay entirely within Astral.
It is also possible to use the Auto SDK’s @autonomys/auto-xdm package to submit these transactions if you’d like to automate them in some way.