The presentation will give the basic idea about what is blockchain technology, it's architecture, main features, types of blockchain network and other things that will make your fundamentals clear.

1. Workshop on
BLOCKCHAIN
TECHNOLOGY
Presented by:
Rashi Singh

2. OUTLINE
• Blockchain Architecture
• Blockchain Mining
• Structure of a Blockchain
• Blockchain Header
• Merkle Tree
• How Blockchain works?
• Types of Blockchain Networks
• Centralized vs. Distributed Ledger.

3. What is
Blockchain Technology?
• Decentralized database which stores information in the form of transactions.
• A cryptographically secure, shared, distributed ledger.
• Immutable transactions are written on this distributed ledger on distributed nodes.

4. Blockchain
• A blockchain consists of data sets which are composed of a chain of data
packages(blocks) where a block comprises multiple transactions (TX 1 to TX N).
• Blockchain is extended by each additional block and hence represents a complete
ledger of the transaction history
• In addition to the transactions, each block contains a timestamp, the hash value of
the previous block, and a nonce.
• This concept ensures the integrity of the entire blockchain through to the first
block.

5. Blockchain Architecture
These are the core blockchain architecture components:
• Node
• Transaction
• Block
• Chain
• Miners
• Consensus (consensus protocol)
– PoW(Proof-of-Work)
– PoS(Proof-of-Stake)

6. Blockchain Mining

7. Consensus Algorithms

8. Structure of Block in
Blockchain
• A block is a container data structure, which brings
together transactions for inclusion in the public
ledger, known as the blockchain.
• Block is made up of header: consists of three sets of
block metadata.
• Version: version number to track software/protocol
upgrades.
• Transaction counter: identifies how many
transactions are stored in current block.
• Block body: where all block transactions are stored.

9. Blockchain Header
• Block Version: software/protocol version.
• Parent Block Hash: connects current block to the
previous block, lying in blockchain.
• Timestamp: Block creation time
• Nonce: counter used for the proof-of-work algorithm.
• nBits: represents the target value.
• Merkle Tree Root Hash: A hash of Merkle tree root of
the block’s transaction.

10. Merkle Tree
• Merkle tree summarize and verify the
integrity of large sets of data.
• A Merkle tree is built by recursively
hashing pairs of nodes until there is only
one hash, called the root hash.
• Also known as Binary Hash Tree.

11. How Blockchain Works?

12. Example of Blockchain
Step1: A trade is recorded.
For example, let’s say Mr
Pink is selling two of his
coins to Mr Green for $100.
The record lists the details,
including a digital signature
from each party.

13. Step 2: The record is checked by the network. The computers in the
network, called 'nodes', check the details of the trade to make sure it is valid.

14. Step 3: The records that the network accepted are added to a block. Each
block contains a unique code called a hash. It also contains the hash of the
previous block in the chain.

15. Step 4: The block is added to the blockchain. The hash codes connect the
blocks together in a specific order.

16. Types of
Blockchain Network
• Public Blockchain: Publicly accessible blockchains are termed as Public Blockchain.
• Private Blockchain: This particular blockchain requires the participants to be invited before they can
be a part of the blockchain
• Hybrid Blockchain: This blockchain is divided into two different types, where some nodes are
private, while the other nodes are public.

17. Features of Blockchain
• Increased Capacity
• Decentralized Technology
• Immutability
• Enhanced Security
• Distributed Ledgers
• Consensus

18. Centralized vs.
Distributed Ledger
A distributed ledger is a network that records ownership through a shared registry.
The best known existing use for the distributed ledger is the cryptocurrency Bitcoin.

19. Centralized vs. Distributed Ledgers
• Blockchain aims to decentralize transactions of assets to the internet
network, via a chain of nodes called a distributed ledger.
• Traditional centralized ledgers functions as a middleman exchange
between the buyer and seller and chargers extra operational fees due to
third party involvement.
• In a blockchain environment, the user has personal access to his asset
via a private key
• If the user chooses to transact their assets, they can do so directly
without the intervention of the third party entity.

20. Advantages of Distributed Ledger
over Centralized Ledger
Factors Centralized Ledger Distributed Ledger
Control Single point of control Decentralized
Failure Single point failure Distributed
Third party
involvement
Unnecessary gateways and
middleman
Peer-to-peer
Change in Data No restrictions Immutable(append only)
Ease of use Easy and intuitive to use Complex to use, and not very
intuitive.
Hackable More susceptible to hacks Difficult to hack

21. Distributed vs.
Decentralized Ledger

22. Opportunities in
Blockchain