POSTER: Deterring DDoS Attacks on Blockchain-based Cryptocurrencies through Mempool Optimization

In this paper, we highlight a new form of distributed denial of service (DDoS) attack that impacts the memory pools of cryptocurrency systems causing massive transaction backlog and higher mining fees. Towards that, we study such an attack on Bitcoin mempools and explore its effects on the mempool size and transaction fees paid by the legitimate users. We also propose countermeasures to contain such an attack. Our countermeasures include fee-based and age-based designs, which optimize the mempool size and help to counter the effects of DDoS attacks. We evaluate our designs using simulations in diverse attack conditions.