“Proof of transaction” to fight 51% attack — the more aging and distributed, the more secure TAU is.
Fight 51% attack — 51% attack is unavoidable on decentralized ledger according to Satoshi, and just happened in BCH community. With 51% power, one can do both short range (double spend or censorship) and long range attack (rebuild a new chain).
TAU aims to make it harder for anyone to obtain 51% of the total power.The most scarce resource to build is “time” rather than equipment and stake. In a blockchain, the transactions are representing “time”. Transactions cost fee to happen, so that it is immune to Sybils.
Checkpoint is used to contain long range attack, TAU will inherit that although it is still at mercy of “weak subjectivity”. For short-range attack, when POT blockchain lives many years, in order to secure 51% POT power, one need to either secure enough miners’ private keys to get power or build own power through same time period. The older the chain, the harder to achieve that, due to time can not be created.
TAU focuses on mobile node to make more people be able to mine and secure the chain. This will make “nothing at stake” hard to implement on massive small forks. POT total mining power will be very distributed among many addresses, it will be hard to form 51% power to fight against network. We recently removed the mining club to make 51% formation even harder, and reduce the block size to 10kb to allow maximum data availability in the network.
For a currency, security is everything.