j"1LAnZuoQdcKCkpDBKQMCgziGMoPC4VQUckMI<div class="post">It doesn't have to be such a breaking change. New nodes could accept old transactions for a long time until most nodes have already upgraded before starting to refuse transactions without PoW. Or, they could always accept old transactions, but only a limited number per time period.<br/><br/>I've thought about PoW on transactions many times, but usually I end up thinking a 0.01 transaction fee is essentially similar and better. 0.01 is basically a proof of work, but not wasted. But if the problem is validating loads of transactions, then PoW could be checked faster.<br/><br/>A more general umbrella partial solution would be to implement the idea where an unlikely dropoff in blocks received is detected. Then an attacker would still need a substantial portion of the network's power to benefit from a DoS attack.<br/><br/><div class="quoteheader"><a href="https://bitcointalk.org/index.php?topic=788.msg8761#msg8761">Quote from: gavinandresen on August 11, 2010, 04:10:56 PM</a></div><div class="quote">Bitcoin's p2p network is subject to various kinds of denial of service attacks.<br/><br/>There, I said it.<br/></div>+1<br/><br/>Any demonstration tests at this point would only show what we already know, and divert dev time from strengthening the system to operational fire fighting.<br/></div> text/html
https://whatsonchain.com/tx/095a52ee6d8cf7db46d0de4bb54065ad4ef697e25ce6fefbddd8948a2ec98ab4