Blockchain Mechanism webinar presentation to the Institute of Engineers and Technology based in Mauritius.

1. Blockchain Mechanism
Understanding the Nitty-Gritty
Charles OkaforMbah
Blockchain Solutions Architect

2. About Me!
- Been in Tech for 15 years
- Blockchain space for 6 years
- Worked on Enterprise and Public Blockchain solutions
- Contributed to Blockchain policy framework drafting
for Nigerian Govt agencies(NITDA, SEC)

3. Blockchain!
Blockchain is a form of distributed ledger technology that make records
immutable, provable and secure using timestamping and hashing to
cryptographically connect blocks of transactions together using defined
consensus mechanism to secure the network.

4. Blockchain: PreHistory!
- David Chaum (eCash, 1983)
- Cynthia Dwork and Moni Naor (Both Cryptographers, 1992), publication
- Adam Back (Hashcash:PoW, 1997)
- Wei Dai (bMoney, 1998) never implemented. publication
- Nick Szabo(bitGold, 1998) never implemented. publication
- Hal Finney (rPoW, 2004)
- Satoshi Nakamoto (Bitcoin Network, 2008/9)

5. Blockchain as DLT
Distributed Ledger Technology is shared
ledger or record amongst a group of
node or computers. Blockchain seems
to be the most popular and widely used
of them all.

6. Asymmetric Encryption: Public Keys Cryptography
- Custodial Wallets
- Non-Custodial Wallets
The general purpose of PKC is to enable secure, private communication using digital
signatures in a public channel where there can be potentially malicious eavesdroppers. In the
context of cryptocurrencies, the goal is to prove that a spent transaction was indeed signed
by the owner of the funds, and was not forged, all occurring over a public blockchain
network between peers

7. Layers of Blockchain
According to Enterprise Ethereum Association Standard. The the Institute of
Electrical and Electronics Engineers also have some standardization going on.

8. MemPool and Forming a Block
Before a transaction get added to a block, it waits in the
memory pool of the network.
A Mempool or pre-chain is where all UNCONFIRMED
transactions sits. It is also known as transaction-in-flight.
A block is added to the blockchain once it fulfills the
mathematical function of providing the right answer
needed for the cryptographic hash. Once successful, it
gets added to the block to continue the chain.

9. Blockchain Trilemma Issue
Majorly associated with Public Blockchains. For Enterprise or
Private blockchains, other consensus mechanism are being
adopted.

10. Blockchain Trilemma Issue(Possible Fixes)
On-Chain Solutions (Protocol layer fix) Off-Chain Solutions
- Shrink transaction data (Bitcoin Core Segwit)
- Block creation time
- Open communication between different native blockchains
(Polkadot)
- Sharding (Ethereum)
- Delegated Proof of Stake (EOS)
- Roll-ups (Ethereum)
- State Channels (Ethereums)
- Raiden (Ethereum)
- Lightening Network (Bitcoin)
- Plasma (Ethereum)
- SideChains(PoA.network - Ethereum)

11. Consensus Algorithms
This is the HOLY GRAIL that solved “Double Spend” and by extension, Byzantine General Fault issue.
These types of algorithms tend to rely on laws of physics (limit on computing speed) or
economics (incentives for honest behaviors or disincentives for dishonest behaviors) to
guarantee agreement; they apply to the cryptocurrency networks in a public setting.
This is the agreement between the nodes/validators in the network on the correctness
of the block added to the blockchain and the history of the blockchain. If a bad
transaction is added to the network, it gets sideline by the other nodes in the network.
- Proof of Work
- Proof of Stake
- Delegated Proof of Stake (Selected Validators)
- RAFT (Vote a leader to create block)
- IBFT (Verifies block created. No leader)
- Proof of Authority

12. Attacking a Blockchain: The Sybil Way!
A Sybil attack is a kind of security threat
on an online system where one person
tries to take over the network by
creating multiple accounts, nodes or
computers.

13. Governance
Depending on the Blockchain or Project there is:
1 Public Blockchain: Miners, Exchanges, Wallet companies, Core Developers, Users
2 Private or Enterprise Blockchain: Consortia
3 Decentralized Autonomous Organizations: Vote tokens and proposals

14. References
- https://en.wikipedia.org/wiki/History_of_bitcoin#:~:text=On%203%20January%202009%2C%20the,of%20second%20bailout%20for%20banks.
- https://en.bitcoin.it/wiki/How_bitcoin_works
- https://en.wikipedia.org/wiki/Proof_of_work#Reusable_proof-of-work
- https://entethalliance.org/how-ethereum-layer-2-scaling-solutions-address-barriers-to-enterprises-building-on-mainnet/
- https://en.wikipedia.org/wiki/Public-key_cryptography
- https://en.wikipedia.org/wiki/Trapdoor_function
- https://www2.cs.duke.edu/courses/fall07/cps212/consensus.pdf)
- https://www.kaleido.io/blockchain-blog/consensus-algorithms-poa-ibft-or-raft
- https://en.bitcoin.it/wiki/Scalability_FAQ
- https://medium.com/@katherine_42300/consensus-protocols-proof-of-work-proof-of-stake-proof-of-authority-raft-and-federated-
207b2889e269
- https://standards.ieee.org/search-results.html?facetValue=4294967230,4294967245&q=Standard
- https://academy.binance.com/en/articles/sybil-attacks-explained

15. Questions about Blockchain Mechanism?
Charles OkaforMbah
charlie4biz@gmail.com
Linkedin.com/in/justcharlz