Design

Implementation

Contract - Code diff

• AvailAttestation.sol - This is the contract which handles the DA attestation verification for AvailDA message bytes
• DataAvailabilityProtocol - It has to be set to AvailAttestation.sol using setDataAvailabilityProtocol function

CDK node

• aggregator component which uses zkevm-synchronizer-l1 library for reading data from Avail DA - code diff
• sequencer-sender component for sending data to Avail DA - Code diff

Explanation

• In the migration of Data Availability protocol for CDK chain, We are going to switch the protocol to AvailDA both on CDK contracts and node
• but this switch can’t change the history of transactions committing (DataAvailabilityMessage) for DAC on L1 chain (PolygonValidium contract)
• To complete switch and healthy functioning of chain, it will require the migrate the history data from DAC to AvailDA, so CDK node (aggregator component) can retrieve the data and fully create the chain
• But as CDK node reads the DA blob references from the L1 chain (PolygonValidium contract), there must be some logic to deviate this DAC blob ref to new AvailDA blob ref (can be centralised server, or contract for more decentralised visibility)

Steps for Migration from DAC to AvailDA