Pool 51pool.org, allegedly created to launch a “51% attack” on the new Ethereum Classic network, has itself become a target of multiple attacks.
It is reported that the pool was launched by an unknown user to gain control of the ETC system through seizure of 51% or more of its processing power. Such an attack, organised by miners and/or supporters of the forked blockchain, can potentially lead to a change in the history of operations, block confirmation of transactions in the network and cause a temporary malfunction of the system. Possibly, the DDoS-attack is performed by supporters of the alternative token to prevent the unethical move.
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http://www.coinfox.info/news/6067-ethereum-classic-enemies-warned-by-ddos-attacks