How Does AuxPoW Leverage the Security of a Larger Blockchain?

Auxiliary Proof-of-Work (AuxPoW) allows blocks mined on a smaller chain (the secondary chain) to be simultaneously validated by the hash power of a larger, more secure chain (the primary chain, often Bitcoin or Litecoin). Miners on the primary chain can include the secondary chain's block header in their own block.

This means that to successfully attack the secondary chain, an attacker would need to overcome the combined hashrate of the primary chain, making a 51% attack economically unfeasible. It essentially piggybacks on the security budget of the dominant chain.

What Is the Main Security Threat That Difficulty Adjustment Helps to Mitigate?
How Does the Threat of Slashing Contribute to the “Cost of Attack” on Ethereum?
What Is the ‘Hash Rate’ and How Does It Measure Network Security?
What Is a 51% Attack and How Does Hashrate Prevent It?
What Are the Key Technical Components Typically Validated in a Blockchain PoC?
Does the Use of AuxPoW Slow down the Block Production of the Primary Chain?
What Is a “Transaction Spam” Attack and How Do Fees Mitigate It?
What Is “Merged Mining” and How Is It Related to AuxPoW?

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