1. Hyperledger Blockchain Integrity

2. Overview Motivation Goal Approach
As a committer, a peer validates each new coming block before committing it to its ledger.
When a peer is hacked, the block data in its ledger can be compromised.
Validating the new coming block does not help to detect any compromised historical block.
Goal
Each peer maintains the correctness of all the blocks in its ledger.
Approach
Each peer periodically validates its blockchain.
Once a broken block is detected, the peer asks its neighbors for a correct block to replace the broken one.

3. Implementation
CheckChainIntegrity(): a separate Go routine when a peer starts.

4. Implementation VerifyChain():
Verifies blockchain within [startBlockNum, endBlockNum] inclusive range.
Set the “CorruptedBlock” flag to true if a corrupted block is found.
Please see this Jira for the VerifyChain() function.
I modified VerifyChain() by
Adding the “CorruptedBlock” flag and the corrupted block ID.
Making it compatible to Hyperledger Fabric V-1.0.0

5. Implementation
requestBlocksInRange(): Replace the broken block and reset the “CorruptedBlock” flag to false

6. Performance
Overhead of validating the blocks

7. Performance
Block retrieval time