Layer 1 Interactions
While Laïka leverages the robust Proof-of-Work security of the Dogecoin blockchain for data storage, it's crucial to acknowledge potential data integrity challenges inherent to PoW systems. Here's a breakdown of these challenges and Laïka's mitigation strategies.
↝ Potential Vulnerabilities of PoW Blockchains
Blockchains like Bitcoin and Dogecoin, secured by PoW, are susceptible to various attacks due to their consensus mechanisms. These attacks, though mitigated by sufficient decentralization, aim to manipulate the blockchain for malicious purposes.
Reorganizations: A specific concern for Laïka is the concept of "reorganizations." In PoW systems, the longest valid chain becomes the accepted blockchain. Occasionally, a longer valid chain might be discovered later, leading to a reorganization where some previously confirmed blocks are discarded.
Reorganizations and Transaction Order: For Laïka, transaction order is critical. Reorganizations on Dogecoin could potentially disrupt the intended order of transactions submitted by sequencers. This disruption could render Laïka transactions invalid.
Smart Contract Limitations on Dogecoin: Dogecoin lacks native smart contract functionality. This eliminates the option of using on-chain logic to verify data integrity and enforce transaction order after potential reorganizations.
Laïka's Solution: UTXO-based Transaction Chains
To address these challenges, Laïka sequencers leverage a clever approach utilizing Dogecoin's core transaction mechanism - Unspent Transaction Outputs (UTXOs).
UTXO Chains: Laïka sequencers treat all their transactions on Dogecoin as a single, linked chain based on UTXOs. Each new transaction spends the output of the previous transaction, creating a chronological sequence.
Genesis UTXO: The first transaction where a sequencer submits block data to Dogecoin becomes the "genesis UTXO" for the chain. This establishes the starting point for subsequent transactions.
Enforced Transaction Order: By relying on a single UTXO chain, sequencers ensure that transactions are processed in the intended order on the Dogecoin blockchain. A reorganization might cause some blocks to be discarded, but the UTXO chain ensures the remaining transactions maintain their correct sequence.
Benefits of UTXO Chains:
Traceability: Anyone can easily trace all Laïka-related data stored on Dogecoin by simply following the UTXO chain starting from the genesis UTXO. This fosters transparency and auditability.
Data Rebuilding: In case of data loss on a sequencer, the entire data sequence can be reconstructed by starting from the genesis UTXO and scanning the subsequent transactions on the Dogecoin blockchain.
Minimum Balances and Sequencing Algorithm: Sequencers are required to maintain minimum balances in their dedicated addresses. The sequencing algorithm prioritizes maintaining the UTXO chain order, ensuring data integrity and facilitating data recovery.