EIP-155 was implemented to prevent replay attacks by using a unique chainId value for different networks.
However, if the chainId remains at 1 and does not change on the potential PoW fork, replay attacks are possible again.
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实施 EIP-155 是为了通过对不同网络使用唯一的 chainId 值来防止重放攻击。
但是，如果 chainId 保持为 1 并且在潜在的 PoW 分叉上没有变化，则可能再次进行重放攻击。
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