Endorsement policy
Now that we understand how a smart contract generates, for a single organization, a signed transaction response comprising the before- and after-images of changed states, we're close to understanding how to generate a multi-party transaction. We're going to see how an endorsement policy is central to this process.
In Figure 6.9, we can see an endorsement policy for the car smart contract we've been discussing:
Figure 6.9: A smart contract has an endorsement policy associated with it
The car contract has an associated endorsement policy: AND(SARA, BOB). This says, "any transaction generated by the car smart contract is only valid if it is signed by Sara and Bob."
In Hyperledger Fabric, every smart contract has an associated endorsement policy to describe the set of signatures required for the transaction that generated it to be considered valid. Multi-party transactions are the core of Hyperledger Fabric—that...