Miles Carlsten will present his MSE talk, "The impact of transaction fees on Bitcoin mining strategies" on Friday, May 6 at 1:30pm in CS 301. The members of his committee are Arvind Narayanan (adviser) and Mark Braverman. The title and abstract follow below. Everyone is invited to attend. Title: The impact of transaction fees on Bitcoin mining strategies Abstract: There are two incentives for Bitcoin miners to mine Bitcoin blocks. The miners are rewarded both from the minting reward of creating a new block and from the transaction fees on the transactions included in the block mined. Traditionally, the minting reward has always been significantly larger than the transaction fees, but as time goes on the minting fee is designed to diminish, and it is expected that the transaction fees will take its place. We look into the unverified claim that once incentives shift to mostly transaction fees, the security of the system will be the same as it was when it was based on minting rewards. We show that this change can lead to very uneven blocks, which can give rational miners an incentive to intentionally try to fork the blockchain. Additionally, we reexamine a previously known alternate mining strategy, known as Selfish Mining, and show that it will become profitable for any miner (regardless of their hash power) to utilize this strategy.