Hyperledger Fabric Network Setup in Block Chain

Step 1/6 : Configure & Start Ordering Service

An Ordering service is configured and started for the network :
$ docker-compose [-f orderer.yml]...

Step 2/6 : Configure and Start Peer Nodes

A peer is configured and started for each Endorser or committer in the network :
$ peer node start ...

Step 3/6 : Install Chain code

Chaincode is installed onto each Endorsing Peer that needs to execute it :
$ Peer chaincode install ...

Join Channels

Peers that are permissioned can then join the channels they want to transact on :
$ peer channel join ...

Endorsement Policies

An endorsement policy describes the conditions by which a transaction can be endorsed. A transaction can only be considered valid if it has been endorsed according to its policy.

Each chaincode is deployed with an Endorsement policy
ESCC (Endorsement ChainCode) signs the proposal response on the endorsing peer
VSCC (Validation System Chaincode) validates the endorsements

Endorsement Policy Syntax

Instantiate the chaincode mycc on channel mychannel with the policy AND ('org1MSP.member')
Policy Syntax : EXPR(E[,E...])
         Where EXPR is either AND or OR and E is either a principal or nested EXPR

Principal Syntax : MSP.ROLE
         Supported roles are : member and admin
         Where is the MSP ID, and ROLE is either "member" or "admin"

N-out-of-K policy specification also possible (e.g., 3 out of 5 peers in the channel must endorse)

Endorsement Policy Examples

Examples of policies :

Request 1 signature from all three principals
- AND ('Org1.member', 'Org2.member', 'Org3.member')

Request 1 signature from either one of the two principals
- Or ('Org1.member', 'Org2.member')

Request either one signature from a member of the Org1 MSP or (1 signature from a member of the Org2 MSP and 1 signature from a member of the Org3 MSP)
- Or('Org1.member', AND('Org2.member', 'Org3.member') )

Hyperledger Fabric : Additional Information