Authentication Methods and Apparatus Utilizing Hash Chains
    81.
    发明申请
    Authentication Methods and Apparatus Utilizing Hash Chains 有权
    使用哈希链的认证方法和设备

    公开(公告)号:US20070279227A1

    公开(公告)日:2007-12-06

    申请号:US11768608

    申请日:2007-06-26

    申请人: Ari Juels

    发明人: Ari Juels

    IPC分类号: G08B13/14

    摘要: A first processing device, which may be, for example, a wireless authentication token or an RFID tag, comprises a memory, a processor coupled to the memory, and interface circuitry coupled to the processor. The processor is operative to control the output of authentication information via the interface circuitry, where the authentication information comprises a sequence of values corresponding to images of a hash chain. A given one of the values of the sequence is utilized by a second processing device to generate a modified value suitable for providing joint authentication of the first and second processing devices.

    摘要翻译: 可以是例如无线认证令牌或RFID标签的第一处理设备包括存储器,耦合到存储器的处理器和耦合到处理器的接口电路。 处理器可操作以经由接口电路来控制认证信息的输出,其中认证信息包括对应于散列链的图像的一系列值。 序列的给定值之一被第二处理装置利用以产生适于提供第一和第二处理装置的联合认证的修改值。

    Cryptographic countermeasures against connection depletion attacks
    82.
    发明授权
    Cryptographic countermeasures against connection depletion attacks 有权
    针对连接耗尽攻击的加密对策

    公开(公告)号:US07197639B1

    公开(公告)日:2007-03-27

    申请号:US09496824

    申请日:2000-02-02

    IPC分类号: H04L9/00

    摘要: This invention relates to cryptographic communications methods and systems that protect a server from a connection depletion attack. Specifically, the invention presents a method for allocating a resource comprising the steps of receiving a resource allocation request from a client, imposing a computational task and a time limit for correct completion of the task upon the client, verifying that the task was performed correctly within the time limit, and allocating the resource if the task was correctly performed within the time limit.

    摘要翻译: 本发明涉及保护服务器免受连接耗尽攻击的密码通信方法和系统。 具体地说,本发明提出了一种分配资源的方法,包括以下步骤:从客户端接收资源分配请求,对客户端进行任务的正确完成,对计算任务进行计算任务和时间限制,验证任务是否在 时间限制,如果任务在时间限制内正确执行,则分配资源。

    Mixing in small batches
    83.
    发明授权
    Mixing in small batches 有权
    小批量混合

    公开(公告)号:US06813354B1

    公开(公告)日:2004-11-02

    申请号:US09521681

    申请日:2000-03-09

    IPC分类号: H04L918

    摘要: A highly efficient mix network for small numbers of inputs is provided. Four data messages would be a typical number of inputs. The structure of sorting/permutation networks is used to permute the input. This is done in a way that changes the position of pairs of items. A mix network is provided which is highly efficient on small input batches and is robust and private in the face of collusion by any minority set of mix servers. Additionally, the mix network method and apparatus has the feature of being publicly verifiable because the mixing method yields a transcript of results that can demonstrate to a third party that the mix proceeded correctly. An apparatus comprised of a plurality of mix servers is provided. Each mix server includes a randomizer network. Each randomizer network receives a plurality of input data messages and performs re-encryption and permutation operations on the plurality of input data messages to form a plurality of output data messages. The randomizer networks of the plurality of mix servers are arranged in a chain so that the first randomizer network of the first mix server in the chain receives its plurality of input data messages and provides its plurality of output data messages to the next randomizer network of the following mix server in the chain. Each randomizer network is comprised of a plurality of randomizers, wherein each randomizer receives first and second input data messages and produces first and second output data messages, wherein the first output data message is a re-encryption of either the first or the second input data message and the second output data message is a re-encryption of the other input data message. A bulletin board having computer memory may be provided, to which each mix server produces proof that each randomizer of each randomizer network has re-encrypted and permuted in a proper manner.

    摘要翻译: 提供了一种用于少量输入的高效混合网络。 四个数据消息将是典型数量的输入。 排序/排列网络的结构用于排列输入。 这样做可以改变项目对的位置。 提供混合网络,在小批量输入批次上是高效的,并且在任何少数混合服务器的串通的情况下是强大的和私有的。 此外,混合网络方法和装置具有可公开验证的特征,因为混合方法产生可以向第三方证明混合正确进行的结果的抄本。 提供了由多个混合服务器组成的装置。 每个混合服务器包括随机网络。 每个随机化网络接收多个输入数据消息,并对多个输入数据消息执行重新加密和置换操作以形成多个输出数据消息。 多个混合服务器的随机化网络被布置在链中,使得链中的第一混合服务器的第一随机化网络接收其多个输入数据消息,并将其多个输出数据消息提供给下一个随机化网络 以下混合服务器在链中。 每个随机化器网络由多个随机化器组成,其中每个随机化器接收第一和第二输入数据消息并产生第一和第二输出数据消息,其中第一输出数据消息是第一或第二输入数据的重新加密 消息,第二输出数据消息是另一输入数据消息的重新加密。 可以提供具有计算机存储器的公告板,每个混合服务器向其提供证明,每个随机化器网络的每个随机化器都以适当的方式重新加密和置换。

    Methods and apparatus for verifying the cryptographic security of a selected private and public key pair without knowing the private key
    84.
    发明授权
    Methods and apparatus for verifying the cryptographic security of a selected private and public key pair without knowing the private key 失效
    用于在不知道私钥的情况下验证所选择的私钥和公钥对的加密安全性的方法和装置

    公开(公告)号:US06411715B1

    公开(公告)日:2002-06-25

    申请号:US09188963

    申请日:1998-11-10

    IPC分类号: H04L908

    摘要: Methods and apparatus are disclosed for demonstrating that a public/private key pair is cryptographically strong without revealing information sufficient to compromise the private key. A key pair can be shown to be cryptographically strong by demonstrating that its modulus N is the product of two relatively large prime numbers. In addition, a key pair can be shown to be cryptographically strong by demonstrating that N is cryptographically strong against Pollard factoring attacks, Williams factoring attacks, Bach-Shallit factoring attacks, and weighted difference of squares factoring attacks.

    摘要翻译: 公开了用于示出公共/私人密钥对在密码学上很强而不显露足以危及私钥的信息的方法和装置。 通过证明其模数N是两个相对较大素数的乘积,密钥对可以被证明是加密的。 此外,通过证明N对波拉德因子分解攻击,威廉姆斯因子分解攻击,巴赫 - 沙利特因子分解攻击以及平方分解攻击的加权差异具有密码学强度,可以显示密钥对密码。

    Executable digital cash for electronic commerce
    85.
    发明授权
    Executable digital cash for electronic commerce 有权
    可执行电子商务数字现金

    公开(公告)号:US6157920A

    公开(公告)日:2000-12-05

    申请号:US134012

    申请日:1998-08-14

    摘要: The invention provides techniques for implementing secure transactions using an instrument referred to as "executable digital cash." In an illustrative embodiment, a first user generates a piece of digital cash representing an offer made by that user. The piece of digital cash includes a digital certificate authorizing the first user to make specified transfers, and an offer program characterizing the offer. The piece of digital cash is broadcast or otherwise transmitted to one or more additional users, utilizing a mobile agent or other suitable mechanism, such that a given one of these users can evaluate the offer using the offer program. For example, a second user could execute the offer program with a specific bid as an input to determine what that user would receive upon acceptance of his bid. If the result is acceptable to the second user, that user generates a bid capsule including the bid, the corresponding output of the offer program, and another certificate authorizing the second user to make the transfer specified in the bid. The bid capsule is submitted to an institution for processing in accordance with a policy which may be specified in the piece of digital cash. The institution selects one or more winning bids and implements the corresponding transactions. Digital signatures generated using secret keys associated with the certificates of the first and second users are utilized to ensure adequate security for the transmitted offer and bid information.

    摘要翻译: 本发明提供了使用称为“可执行数字现金”的仪器实现安全交易的技术。 在说明性实施例中,第一用户生成表示该用户提供的报价的数字现金片。 该数字现金包括授权第一个用户进行指定的转账的数字证书,以及表征报价的报价方案。 使用移动代理或其他合适的机制将该数字现金广播或以其他方式传送到一个或多个附加用户,使得这些用户中的给定的一个可以使用提供程序来评估报价。 例如,第二用户可以以特定出价作为输入来执行报价方案,以确定在接受投标时用户将收到什么。 如果第二用户的结果是可接受的,则该用户生成包括出价的出价胶囊,要约程序的相应输出,以及授权第二用户进行投标中指定的转移的另一证书。 投标胶囊根据可以在数字现金中指定的政策提交给机构进行处理。 该机构选择一个或多个中标并实施相应的交易。 使用与第一和第二用户的证书相关联的密钥生成的数字签名用于确保所传送的报价和投标信息的足够的安全性。