In the recent days – when Ethereum’s Ether-blockchain forked into ETH and ETC – we could not do else but read the term “Replay Attack”. If you wondered what exactly a replay attack is, continue to read. I will explain.
The basis of the Replay Attack is the fact that all wallets which contained Ether at the time of the fork will credit their corresponsing Ethereum Classic wallets with ETC. So, if you had, say, 100 ETH in your wallet, then you’ll be credited with 100 ETC.
But that’s not an automatic process (well, it is, but only under certain circumstances): it only works on exchanges which support the quasi-new Ethereum Classic chain.