查询词典 transposition cipher

The validity of the provable security of counter with cipher block chaining message authentication code mode and cipher-based message authentication code mode was studied and proved. The illustrations of different communications' encryption have been developed.

对分组密码算法CCM、CMAC加密模式进行描述，用可证安全性理论对它们进行相关研究和证明，并对各种证明情况在不同通信环境下的使用作出说明。

In addition, algorithms used in PBE were discussed in details, including International Data Encryption Algorithm, Advanced Encryption Standard of U.S., safe Hash function named SHA-1, Pseudo Random Number Generator.The modes of operation in blok cipher,such as Electronic Code Book, Cipher Block Chaining, Cipfertext Feedback and Output Feedback,are described in the thesis.

采用DSP TMS320C5409汇编语言编制了以上各种算法，在DSP上实现了一个口令加密系统，数据加密速度达到3Mb/s以上，并实现密钥的安全管理，能满足个人PC机脱离主CPU加密大量数据的需要。

Chapter 2 clarifies the cryptographical foundation, which includes the symmetrical cipher technology, unsymmetrical cipher technology and digital envelope .

包括对称密码技术，非对称密码技术和数字信封技术，并详细分析了DES算法和RSA算法。

In essence, stream cipher is such a pseudorandom generator that its chaos sequence of output and random sequence are computational indistinguishability; and the aim in designing block cipher materially is to design a pseudorandom permutation which is computationally indistinguishable from random permutations.

实际上，序列密码本质上就是一个伪随机生成器G，其输出的乱数序列和随机序列是计算不可分辨的；而分组密码的设计目标实质上就是设计一个伪随机置换，它与随机置换是计算不可分辨的。

The S box was constituted with the multiplication inverse element affined transformation in GF(2) of all elements of limited field GF(28),with S box s nonlinear byte changed,ciphered text attained the ideal status of the even of difference and the linear of deviation,and increased the capability of the AES algorithm of anti beating the difference cipher of analysis and linear cipher of analysis.

S盒由有限域G F(28)上所有元素的乘法逆元及在域G F(2)上的仿射变换构成，经过S盒的非线性字节代换，密文的差分均匀性和线性偏差都达到较理想的状态，提高了A E S算法抗击差分密码分析及线性密码分析的能力。

The diffusion structure has important impact on the rate of the diffusion and safety intensity for block cipher.Using the linear transform which has branch numbers as large as possible as the diffusion structure is a main method to devise block cipher.The linear transform is usually achieved by constructing the invertible matrix.

扩散结构的好坏直接影响了分组密码的扩散速度和安全强度，以分支数尽可能大的线性变换为分组密码算法的扩散结构是设计分组密码的一种重要方法，线性变换的构造可通过可逆矩阵的构造完成。

When operating a cipher in CBC mode, the plain text must be padded to the cipher's block size in an unambiguous manner so that the padding can later be removed.

当经营CBC模式密码，纯文本必须填充到密码的块大小可以很清楚地让填充以后可以删除。

This invention discloses a safety authenticating method for PC customer end including PC customer end presents registration request to a service via ID number and cipher, the server makes the first authentication based on customer ID number and the cipher to generate a field of reauthentication if it's passed to be fed back to PC customer end along with the finished authentication message; when PC customer end makes calls, it will send ID number and field of reauthentication during registration to media gate controller which transfer the ID number field of reauthentication to be server for second time authentication and refuse the calling if it's not passed, or receive the calling and feeding back the called information.

要约 本发明公开了一种PC客户端的安全认证方法，包括：PC客户端通过用户ID号码和密码，向服务器发起登录请求；服务器根据用户ID号码和密码进行第一次认证，若认证通过，生成一个用于再次认证的字段，并随认证通过消息返回给PC客户端；当PC客户端发起呼叫时，将用户ID号码和登录时获得的再次认证的字段一起传送给媒体网关控制器；媒体网关控制器将该用户ID号码、再次认证的字段一起传送给服务器进行第二次的认证，若认证没有通过，则拒绝呼叫，否则接受呼叫返回被叫信息。

The block cipher with a substitution permutation network is the best known and widely used block cipher system.

包含代替置换网络的分组密码是一种广泛使用的分组密码系统。

One of the simplest examples of a substitution cipher is the Caesar cipher, which is said to have been used by Julius Caesar to communicate with his army.

对一替代密码的一个最简单的例子是凯撒密码，据说是被凯撒用于与他的军队。

"Second Life is remarkably easy to work with, and is very popular,"

"第二次生命是显着容易的工作，并且很受欢迎，"

For example, we usually assume that materials are homogeneous and isotropic and free of internal defects or flaws.

为了得到适合有限元分析的模型，我们必须经过如图2所示的简化步骤。