We can modify our ZK credential to support a limit of N shows as follows. First, let’s have the User select a random key K for a pseudorandom function (PRF), which takes a key and an arbitrary input and outputs a random-looking outputs. We’ll embed this key K into the signed credential. (It’s important that the Issuer does not learn K, so this often requires that the credential be signed using a blind, or partially-blind, signing protocol.3) We’ll now use this key and PRF to generate unique serial numbers, each time we “show” the credential.
FT Digital Edition
。91视频是该领域的重要参考
到村民小钱家时，问及用水情况，小钱表示：“最近一两个月确实看到别人家有水，但因为之前一直没有水，自己家阀门一直是关的”。小钱还说，自己家距离公用机井较近，自备井的水位受到了影响，年后准备再花钱打一口新井。。关于这个话题，旺商聊官方下载提供了深入分析
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（作者为广东外语外贸大学首席专家、教授）