Contra-*: Mechanisms for Countering Spam Attacks on Blockchain's Memory Pools
This addresses security and performance issues for blockchain users and systems, but it is incremental as it builds on existing mempool management concepts.
The paper tackles spam attacks on blockchain memory pools, specifically Bitcoin, by proposing Contra-*, a set of countermeasures using fee, age, and size prioritization to reduce mempool size and mitigate DoS effects, with evaluation through simulations showing effectiveness under various attack conditions.
Blockchain-based cryptocurrencies, such as Bitcoin, have seen on the rise in their popularity and value, making them a target to several forms of Denial-of-Service (DoS) attacks, and calling for a better understanding of their attack surface from both security and distributed systems standpoints. In this paper, and in the pursuit of understanding the attack surface of blockchains, we explore a new form of attack that can be carried out on the memory pools (mempools) and mainly targets blockchain-based cryptocurrencies. We study this attack on Bitcoin mempool and explore the attack effects on transactions fee paid by benign users. To counter this attack, this paper further proposes Contra-*:, a set of countermeasures utilizing fee, age, and size (thus, Contra-F, Contra-A, and Contra-S) as prioritization mechanisms. Contra-*: optimize the mempool size and help in countering the effects of DoS attacks due to spam transactions. We evaluate Contra-* by simulations and analyze their effectiveness under various attack conditions.