Dan Held, Kraken ’s director of business development, highlighted the issues related to the Bitcoin security model in the latest podcast show and the role of transaction fees in the ecosystem. In the next 30 days, Bitcoin will experience the third block reward halving, which, according to Held, may have an impact on security. He pointed out: "In the long run, Bitcoin's security is the most important. Whether its security model can withstand attacks, one of the core parts is to focus on block rewards, which consists of block subsidies and transaction fees. We It should be reviewed whether transaction fees will replace block subsidies in a meaningful way and whether they are sufficient to ensure the security of the network. "Held emphasized that when it comes to Bitcoin and cryptocurrencies, users will always switch to a more secure blockchain.