This is a short outline of features and changes needed to bring CC sector upgrades into reality

Intro:

Since 90+% of sectors in the Filecoin Network are CC sectors, having a protocol that allows for updating CC sectors to store real data without incurring in a full re-sealing would massively improve our network in terms of the amount of real data stored through it.

Relevant docs/links:

• https://github.com/filecoin-project/FIPs/issues/131 - FIP Issue
• https://docs.google.com/document/d/1lerNbgVMBBEDOHC4dqexiS-IKUDOBOy_eTu7fjyv5gs/edit# - Lightweight Sector Updates in Filecoin

Implementation breakdown, per component:

Actors:

• Finalizing the construction
  • One message
• Actor update to v6
• DeclareUpdate implementation
  • Looks like we won't need this message
• ProveCommitReplicaUpdate implementation
• Remove old cc sector upgrade path
• Actors Tests
• State migration

Proofs:

• New: Sector upgrade circuit
  • Circuit design
  • Audit
  • Implementation
  • Phase 2 Trusted Setup
• Encoding Decoding function
• Integration into the system
• New API endpoints
  • EncodeNewDeals (encode a set of new deals into given CC replica)
  • VerifyReplicateUpdate
  • ComputeReplicaUpdateProof