Cardano A Short Dive

Proof of stake (PoS) Blockchain

Ledger properties

Persistence states that once a node of the system proclaims a certain transaction as “stable,” the remaining nodes, if queried and responding honestly, will also report it as stable.

Liveness ensures that once an honestly generated transaction has been made available for a sufficient amount of time to the network nodes, say u time steps, it will become stable

Ledger =List[Transaction]

Leader Node Election

In each epoch a set of randomly selected stakeholders form a committee which is then responsible for executing the coin-flipping protocol. The outcome of the protocol determines the set of elected stakeholders that will execute the protocol in the subsequent epoch, as well as the outcomes of all leader elections for the epoch

Rewards

Incentive structure of the protocol to mitigate attacks like “block withholding” and “selfish-mining” by design.

Delegation to allow protocol to scale even if stakeholders are highly fragmented. Delegation mechanism can enable stakeholders to delegate their “voting rights,” i.e., the right of participating in the committees running the leader selection protocol in each epoch. Stakeholders can revoke their delegative appointment anytime.

Attacks

Double spending attacks- persistence ensures that once the transaction is confirmed by an honest player, all other honest players from that point on will never disagree regarding this transaction

Grinding attacks — Coin tossing provide uniform randomness

Transaction denial (censorship) attacks — liveness ensures that, provided the transaction is attempted to be inserted for a sufficient number of slots by the network, it will be eventually confirmed

Desynchronization attacks — security as long as parties with less than 50% of stake get desynchronized. If more than 50% parties get desynchronized protocol can fail

Bribery AttacksMalicious slot leaders who agree to deliberately attack the system not only risk to forego any potential profit they would earn from behaving honestly but may also risk to lose equity due to currency devaluation

Other attacks considered and mitigations— Long-range attacks, Nothing at stake attacks, Past majority attacks, Selfish-mining

Wallet Addresses Types

Base addresses — A base address directly specifies the staking key that should control the stake for that address.

Pointer addresses — A pointer address indirectly specifies the staking key that should control the stake for the address.

Enterprise addresses — Enterprise addresses carry no stake rights, so using these addresses means that you are opting out of participation in the proof-of-stake protocol (e.g. exchanges and other organizations)

Reward account addresses — Reward account addresses are used to distribute rewards for participating in the proof-of-stake protocol, Account-style accounting not UTXO, Funds cannot be received via transactions

EUTXO — The Extended UTXO Model

UTXO outputs from being a pair of a validator ν and a cryptocurrency value value to being a triple (ν, value, δ) of validator(script), value, and a datum δ, where δ contains arbitrary contract-specific data (e.g. meta-data to specify any validity constraints on consuming transaction).

Each EUTXO contains value and conditions which allow it to be consumed deterministically and by which validator(script)

Hard Fork

In most blockchains, a hard fork indicates block changes or a change to their interpretation. A hard-forked chain will be different from the previous version and that the history of the pre-forked blockchain will no longer be available.

In Cardano the Hard-fork are smooth transition to new protocol while saving the history of previous blocks.

Tokens on Cardano

Tokens on Cardano are native assets just like ADA and inherits all functionality and security of Cardano including governance. There is no need for writing ERC20 or ERC721 Smart Contract.

Transaction

Cardano support multi assets and multi signatures within one transaction

Transactions have a Set of inputs but a List of outputs

Determinism — Users can reliably compute how much they will need to pay ahead of time. Unlike Ethereum there is no possibility of partial fee and resource consumption during transaction or smart contract execution

Smart contract

A smart contract is an automated digital agreement, written in code, that tracks, verifies, and executes the binding transactions of a contract between various parties. The transactions of the contract are automatically executed by the smart contract code when predetermined conditions are met. Essentially, a smart contract is a short program whose inputs and outputs are transactions on a blockchain.

Smart contract development and deployment

Plutus — Based on Haskell functional programing. Code is divided into two parts on-chain and off-chain code. On-chain code updates the Cardano block-chain ledger and off chain code is executing business logic.

Marlow — A visual editor for building contract without writing low level code. Visual editor enables business domain expert to write and verify written contract meet all business requirement.

Glow — a domain specific language for writing dApps on Cardano blockchain

References:

https://eprint.iacr.org/2016/889.pdf

https://docs.cardano.org/core-concepts/cardano-addresses

https://docs.cardano.org/new-to-cardano/what-is-a-smart-contract

The Extended UTXO Model

--

--

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store