Verkle Trees - Preimages generation & distribution

Why is this relevant for the Verkle conversion?

• We have to migrate all the data from MPT to VKT
• The keys in MPT are hashed
• We need the preimage of the hash to rekey it into the VKT
• Thus, we need all the preimages of the MPT tree

Overlay Tree overview & timeline mental model

Current proposed strategy

How to decide the right moment for Slot C?

Database generation and validation

• Who generates the database? (TBD)
• Can people easily verify it? (Yes)

Database format

• Can be easy and efficient
• Flat file with [20 byte | 32 byte] ordered values
• No lookups, sequential read in the exact expected order
• Redundancy?

How is the database distributed?

• Out of protocol:
  • Multiple independent CDNs
  • Torrent
• In protocol:
  • Build sub-protocol allowing clients to share file through peers

Most important question

• How we distribute the preimage database? (In-protocol or out-protocol?)