Blockchain Developer
What is Enterprise Blockchain
Blockchain which is used for Enterprises known as Enterprise Blockchain. Hyperledger is one of the examples where we use fabric, Sawtooth etc to develop enterprise specific applications.
Enterprise blockchain are also known as permissioned blockchain as participants are known to each other and blockchain is not open to everyone.
Enterprise Blockchain is different from Public Blockchain in many aspects as this is mainly designed fro Enterprises.
Difference between Enterprise and Public Blockchain or why we need Enterprise Blockchain
Features of Enterprise Blockchain
Blockchain is Immutable
Cost saving by eliminating middleman
High availability
High Transparency
Automation of manual processes
Increase trust
Examples of Enterprise Blockchain
Hyperledger Fabric
Corda
Qurom
What is Hyperledger?
Hyperledger was initiated by Linux foundation as a base project to create blockchain based applications.
Hyperledger is one of most popular software for enterprise blockchain
What is Hyperledger Umbrella Project?
What is Hyperledger Fabric?
Hyperledger Fabric is a software that helps developers to develop enterprise blockchain solutions.
Features of Hyperledger Fabric
· It features a plug-and-play consensus.
· Support different programming languages for chaincode development
· Faster transaction rate.
· It offers a flexible approach to data privacy – it performs data isolation via ‘channels,’ data sharing on a need-to-know basis by leveraging private data ‘collections.’
· Offer different SDK’s
What is channel in Hyperledger Fabric?
Channel is one of very important feature of Hyperledger fabric that helps participants to have secrets transactions without letting the whole network know.
This feature is not available in Public blockchain as each transaction is seen by anyone but in Fabric you can restrict who can see & do what.
Can we have multiple channel in Fabric Network?
Yes, there can be n number of channels in a network, but overuse of channel is also not recommended.
What is MSP (Membership service Provider)?
1. Contains list of parties/actors involved in Blockchain network
2. Provide identity to each participant
What is Fabric CA?
It is a certificate authority component which can integrate existing registry like LDAP
MSP leverages fabric CA component
What is ACL (Access Control List)?
By using Access Control List (ACL)
1. Handle permission for parties involved
2. Handle permission at channel level also
What is Committing Node?
No, not all nodes keep copy of ledger, only few nodes keep that and that nodes are known as Committing nodes.
What is Endorsing Node?
No, not all nodes execute chaincode , only few nodes do that and that nodes are known as endorsing nodes
What is Ordering service?
Sequence of transactions is very important in Blockchain and that is maintained by Ordering node.
What is State Database?
List down the high level steps involved in Hyperledger fabric Transaction
Step 1: Client start the transaction
Step 2: Validation of client and transaction
Step 3: Endorsing peer simulate the transaction and send response back to client
Step 4: Verification of responses
Step 5: Broadcast the transaction to Ordering service
Step 6: Order the transaction and put to block
Step 7: Block validation by peers
Step 8: Add block to ledger
What is the default consensus algorithm used in Fabric?
It use PBFT where we look for 2/3rd Majority to proceed further.
In which scenario the transaction not added to Block?
· When consensus is not reached
· Transaction is invalid
Can any client connect to network and send the transaction?
No, only authorized clients can send the transactions. In the validation step, client identity is checked if that does not match then transaction is nor processed fur
List down the prerequisites steps for Hyperledger Fabric setup
Operating System: Ubuntu Linux 14.04/16.04 (64 bit)
git & curl: latest version
go version: 1.13.x
Gradle
Nodejs: 8.9 and higher with the exception of 9
libtool: latest version
Docker Engine: 17.06.2 or higher
Docker Compose: 1.14 or higher
Python: 2.7.x
Why you need Docker engine for Hyperledger fabric?
Hyperledger fabric uses different docker containers, like ordering service has its own docker container, chaincode has its own etc.
Why you need to install go language?
Go language is used to develop the smart contracts (chaincode) in Hyperledger Fabric.
Why you need Gradle?
Gradle is build automation tool needed when you use Java as programming language for chaincode development.
Blockchain developer is one of the fastest-growing sectors. Companies are looking for blockchain developers to make new implementations, advance their current systems, and get ahead in the industry.
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