HyperLedger Fabric: Technical Terms

LEDGER: Stored Data

we will be storing two things in the blockchain

• World State ( Current State: what do we "have" now )
• Transaaction Log ( History: everything that happend before )
  • this data is synced between peers ( whenever a peer updated his ledger, the other peers need to add that transaction to their ledger )

CTF: Crash Fault Tolerance

guaranties to withstand system failures, such as crashes, network partitioning.

• HyberLedger Fabric uses Kafka for that

PEER: a user in the network

a user needs to be "certified" ot get identified as a peer ( something to prove that u are who u saying u are , b7al carte nationale / passport )

• every transaction a peer does need to be "signed" by it's certificate to be valid
• every peer has its own copy of the LEGDER

P2P : Peer to Peer network

CERTIFICATE AUTHORITY

it will be the one to "certify" the peers ( make them valid/trusted users )

SMART CONTRACT == CHAINCODE

with it we can initiate a transaction

MEMBERSHIP SERVICE PROVIDER

specifies which peers are allowed to be a part of the network and which aren't ( so getting a certificate from a CA [Certificate Authority] doesnt necessary mean u are a part of the network) it also specefied the rules of a network

Block

a block is a transaction, so every transaction that's being done == a block needs to be add to the ledger

Orderer Peer: ( Writer )

It's the one that writes/add blocks to the peer's ledgers

Channel

it's like a group, only the peers in a channel can see it's ledger .

• Multiple channels can exist in the same blockchain network

Application

• a user is outside the network he connect to it through a Smart Contract which communicates directly with the Peer who can acces a channel directly

Endorsement

when a Peer allows an Application to do a transaction in a Channel ( Note: allowign a transaction doesnt mean it's done, it just means it could happen )

Transaction

• Application send a transaction request to a Peer
• Peer send a confirmation message ( endorssement / license ) to the Application allowing it to do the transaction
• Application sends the transaction with the endorssement to the Orderer Peer
• Orderer Peer verifies the endorssemet, then allows the tranasaction to happen. which means a block needs to be added to the ledger
• Orderer Peer notifies the Peer in the network that a new block is present and u should add it to his ledger