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1. What is Monero (XMR)?
Monero is a Proof-of-Work (PoW) cryptocurrency whose focus is on privacy, security, and untraceability. Its first block was mined in 2014.
Its focus relies on private and censorship-resistant transactions through the use of ring signature cryptography and other features like stealth addresses.
Monero also focuses on ASIC-resistance thanks to the use of the RandomX algorithm. Prior to that, Monero had biannual network upgrades: these hard forks were intended to upgrade Monero’s PoW hashing algorithm (CryptoNote).
Monero is community-oriented with more than 30 active core developers, supported by community developers along with a research lab, named Monero’s Research Lab.
Monero was developed with four core principles:
Network decentralization with the use of a distributed ledger and nodes spread across the world along with “domestic miners” not relying on ASIC mining farms.
Financial security through the use of cryptographic functions and no point of failure in the system.
Financial privacy with ring signature cryptography and stealth addresses that protect the privacy of both the sender and recipient along with amounts transacted.
Fungibility i.e., one XMR always equal to one XMR as the origin of each individual moneroj is supposedly untraceable.
2. Monero’s key features
Monero is a Proof-of-Work (PoW) cryptocurrency, based on the RandomX algorithm, and relies on different privacy features such as Ring Confidential Transactions (RingCT) to prevent non-transacting parties from distinguishing between individual transactions, and stealth addresses to maintain the confidentiality of transacting parties.Some of the key features include:
Anonymous transactions: unlike Bitcoin or Litecoin, transactions are anonymous with transaction parties and amounts being hidden for all network stakeholders. Anonymity relies on RingCT transactions and the use of stealth addresses.
Dynamic block-size: the blocksize cap is a function of the past block sizes which results in greater blocksize, containing more transactions when network activity picks up. Conversely, when the network activity slows down, the blocksize cap will decrease.
ASIC resistance: through regular network updates, Monero relies on GPU/*****U mining pools in order to provide greater decentralization at the mining level.
2.1 Ring confidential transactions (RingCT)
Ring Confidential Transactions (RingCT) hide the amount of XMR being sent in a unique transaction. Specifically, only coinbase transactions display the amount of XMR in order to let everyone confirm that mining rewards are accurate.Ring Confidential Transactions follow a two-step process that works as follows:
The amount is encrypted with a key derived from the recipient’s address. This encrypted amount can only be decrypted by the recipient.
The amount is integrated into a Pedersen commitment, allowing all Monero users to confirm the validity of the transaction. Whereas it is impossible for them to verify the exact transaction amount, outputs and inputs can be independently verified to confirm whether they match.
2.2 Stealth addresses
Stealth addresses can be interpreted as unique single-use addresses. One-time addresses are used by both the recipient and the sender. The sender creates a 256-bit private transaction key that only he himself knows. This number is multiplied by the recipient's public address. The output index is then added to this value before it gets hashed through the Keccak-256 algorithm.Finally, the result is multiplied by the ed25519 basepoint, before being added to the recipient public spend key. The final result is the stealth address.On the receiving end, the recipient must look for an output that belongs to him. Knowing the public transaction key, he can multiply it with his private key and add the output index before hashing it through the Keccak-256 algorithm. Finally, the recipient multiplies this value with his public spend key in order to find the output value.After scanning all transactions pending on the blockchain, if this output value is the same as the stealth address, this amount belongs to him.
2.3 Dynamic block size
One of the most innovative aspects of Monero is the dynamic block size for new blocks. Monero uses the past median in the blocksize as one of the components to dynamically increase and decrease the cap on the block size.Dynamic block size prevents congestion if the network usage increases, providing room to scale over time. However, some research companies (e.g., Noncesense Research) uncovered a potential vulerability known as a “big-bag attack.”. Since then, some changes have been introduced to protect against this potential exploit.
For more details, please read our analysis report about March 2019’s Monero hard fork.
2.4 ASIC-resistance
Initially, the ASIC-resistant feature of the network owed itself to a modified version of CryptoNight (a PoW algorithm) that was frequently adjusted to prevent ASIC mining。However, since December 2019, RandomX has replaced CryptoNight. Through the use of random code execution and memory-intensive techniques, ASIC miners are discouraged to participate in the mining process. In addition, GPUs have also been penalized since the network upgrade.Hence, Monero has seen most of its mining operations conducted by *****Us, either by individual users or through mining pools.
3. Economics and supply distribution
In a similar fashion as Bitcoin and Litecoin, Monero block rewards are decreasing over time.However, after 2022, mining block rewards will be set at 0.6 XMR per block, maintaining a perpetual decaying inflation rate.
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