[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fB-0NI1cDM92lKsbo3ybEkhm9ntJorH2gDu8rbm-TU4o":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":10,"question":17,"related":18,"source":28,"type":29},[],"2024-10-31 19:52:56",163965256,[8,9],"哈西函数出了问题:不用等到sealed envelope发布者公布内容,其他人可以利用输出结果,提前逆向推导出输入是,"涨"或"跌"","输入空间和取值分布出了问题:不用等到sealed envelope发布者公布内容,其他人可以利用蛮力求解的办法提前得到信的内容.如:假设ealed envelope的值为digest1,我们可以H("涨")=digest2 和H("跌")=digest3,对比再要值那个与digest1相等,就能判断出sealed envelope中的内容是"涨"或"跌"了",{"count":11,"courseId":12,"courseImg":13,"courseName":14,"workId":15,"workName":16},52,"f02ef6e361c29d9a67e5550d3ca7108c","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F42ddf1a6b86c68bd645c1a677038bec7.jpg","路由交换与防火墙技术应用2024年","exam_135558854","5.信息链测试","在使用HASH函数的抗碰撞性(collision resistance)、和信息隐藏性(hiding)来是想预测股票涨停的digital commiment的seasled envelope时,假设哈西函数为H,输入参数为"涨"或"跌",那么用H('涨')=digest1 或用 H('涨')=digest2为什么不可以,问题出在哪里",[19,30,38,47,55,62,65,73,80,89],{"answer":20,"createTime":5,"id":21,"options":22,"question":27,"source":28,"type":29},[],163965251,[23,24,25,26],"没有办法解决","更换HASH函数","扩大输入空间,把涨、跌参数后面拼接一个好的随机数nonce,计算出一个digest,把digest和nonce提前发布出去,到时间公布内容时,大家来验证解封内容.因为别人不知道这个随机数nonce,而且输入空间足够大,遍历方法很难在有限时间内找出这个nonce,就无法蛮力求解seasled envelope的内容了","扩大输入空间,把涨、跌参数后面拼接一个好的随机数nonce,计算出一个digest,把digest提前发布出去,而把nonce保存起来,到时间公布内容时,再把nonce一起发布出去,大家来验证解封内容.因为别人不知道这个随机数nonce,而且输入空间足够大,遍历方法很难在有限时间内找出这个nonce,就无法蛮力求解seasled envelope的内容了","在使用HASH函数的抗碰撞性(collision resistance)、和信息隐藏性(hiding)来是想预测股票涨停的digital commiment的seasled envelope时,假设哈西函数为H,输入参数为"涨"或"跌",那么用H('涨')=digest1 或用 H('涨')=digest2用遍历输入空间的值(涨","跌"),对比结果,推断出seasled envelope里面的内容.那如何解决此问题","v1",0,{"answer":31,"createTime":5,"id":32,"options":33,"question":37,"source":28,"type":29},[],163965252,[34,35,36],"存在","在一定条件下存在","不存在,只能通过长时间的实践检验来验证","是否存在一种数学方法可以证明某个HASH函数是具有collision resistance特性的呢",{"answer":39,"createTime":5,"id":40,"options":41,"question":46,"source":28,"type":29},[],163965253,[42,43,44,45],"当x=y时,H(x)<>H(y)","当x=y时,H(x)=H(y)","当x<>y时,H(x)<>H(y)","当x<>y时,H(x)=H(y)","如下描述,哪一个是哈西函数的碰撞(collision)的数学描述",{"answer":48,"createTime":5,"id":49,"options":50,"question":54,"source":28,"type":29},[],163965254,[51,52,53],"1996年,被证实存在弱点,可以被加以破解;2004年,证实MDA5算法无法防止碰撞","从不具备","一直被认为具备","MD5算法具有collision resistance的吗",{"answer":56,"createTime":5,"id":57,"options":58,"question":61,"source":28,"type":29},[],163965255,[59,60],"不可以","完全可以","在使用HASH函数的抗碰撞性(collision resistance)、和信息隐藏性(hiding)来是想预测股票涨停的digital commiment的seasled envelope时,假设哈西函数为H,输入参数为"涨"或"跌",那么用H('涨')=digest1 或用 H('涨')=digest2,是否可行",{"answer":63,"createTime":5,"id":6,"options":64,"question":17,"source":28,"type":29},[],[8,9],{"answer":66,"createTime":5,"id":67,"options":68,"question":72,"source":28,"type":29},[],163965257,[69,70,71],"输入段message,利用哈西函数输出固定大小的字段信息,作为这个message的摘要(digest),对比两个digest的一致性,利用哈西函数的collision resistance特性,就可以判断原message是否一致,以此来判断原信息被修改过n次以上","输入段message,利用哈西函数输出固定大小的字段信息,作为这个message的摘要(digest),对比两个digest的一致性,利用哈西函数的collision resistance特性,就可以判断原message是否一致,以此来判断原信息被修改过几次","输入段message,利用哈西函数输出固定大小的字段信息,作为这个message的摘要(digest),对比两个digest的一致性,利用哈西函数的collision resistance特性,就可以判断原message是否一致,以此来判断原信息是否被修改过","哈西函数的collision resistance的特性有什么价值",{"answer":74,"createTime":5,"id":75,"options":76,"question":79,"source":28,"type":29},[],163965258,[77,78],"哈西函数的输出空间是有限定的(如:256比特位),因为输入空间大于输出空间,那么输入空间和输出空间就是多对一的映射关系,所以会出现哈西碰撞","哈西函数的输入空间是有限定的(如:256比特位),因为输入空间小于输出空间,那么输入空间和输出空间就是一对多的映射关系,所以会出现哈西碰撞","为什么会出现哈西碰撞",{"answer":81,"createTime":5,"id":82,"options":83,"question":88,"source":28,"type":29},[],163965259,[84,85,86,87],"SHA-64","SHA-512","SHA-128","SHA-256","比特币中采用的是那种HASH函数",{"answer":90,"createTime":5,"id":91,"options":92,"question":95,"source":28,"type":29},[],163965260,[93,94],"加密","不加密,但是因为账户地址与实体身份没有对应关系,故此具有一定的隐私保护作用","比特币作为一种加密货币系统,系相关信息(账户地址、转账金额等)是否加密"]