But the scheme 1 does not provide asymmetry (non-repudiation) and the scheme 2 does not resist collusion attack.

但方案1不能够提供非对称性(防抵赖性)，方案2不能够抵抗共谋攻击。

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Additionally, the system had other characters such as integrity of reputation information, non-repudiation, collusion-resisted and retaliation-resisted, which improved the usability of P2P networks.

此外，本体制还具有信誉信息的完整性、不可否认性、防合谋、防报复等特性，从而更好地提高对等网的可用性。

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