How Does the Availability of Specialized Mining Hardware (ASICs) Influence Attack Cost?

The availability of ASICs (Application-Specific Integrated Circuits) increases the attack cost for well-established coins that use those ASICs, but can lower the cost for smaller, newer coins. For a coin like Bitcoin, the massive existing ASIC infrastructure makes it extremely expensive to buy or rent 51 percent of the total hashrate.

However, if a smaller coin uses the same ASIC algorithm, the existing pool of ASIC hashrate can be easily diverted or rented, making the attack cheaper and faster than if the attacker had to rely on less efficient GPU mining.