【信息安全工程师202211】【12】1997年NIST发布了征集AES算法的活动，确定选择Rijndael作为AES算法，该算法支持的密钥长度不包括（12）。

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【信息安全工程师201611】【68】AES结构由以下4个不同的模块组成，其中（68）是非线性模块。

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【信息安全工程师201905】【71-75】The modern study of symmetric-key ciphers relates mainly to the study of block ciphers and stream ciphers and to their applications. A block cipher is， in a sense， a modern embodiment of Alberti's polyalphabetic cipher： block ciphers take as input a block of （71）and a key， and output a block of ciphertext of the same size. Since messages are almost always longer than a single block， some method of knitting together successive blocks is required. Several have been developed， some with better security in one aspect or another than others. They are the mode of operations and must be carefully considered when using a block cipher in a cryptosystem.
The Data Encryption Standard （DES） and the Advanced Encryption Standard （AES） are（72）designs which have been designated cryptography standards by the US government （though DES's designation was finally withdrawn after the AES was adopted）. Despite its deprecation as an official standard， DES （especially its still-approved and much more secure triple-DES variant） remains quite popular; it is used across a wide range of applications， from ATM encryption to e-mail privacy and secure remote access. Many other block ciphers have been designed and released， with considerable variation in quality. Many have been thoroughly broken. See Category： Block ciphers.
Stream ciphers， in contrast to the ‘block’type， create an arbitrarily long stream of key material， which is combined （73）the plaintext bit-by-bit or character-by-character， somewhat like the one-time pad. In a stream cipher， the output（74）is created based on an internal state which changes as the cipher operates. That state change is controlled by the key， and， in some stream ciphers， by the plaintext stream as well. RC4 is an example of a well-known， and widely used， stream cipher; see Category： Stream ciphers.
yptographic hash functions （often called message digest functions） do not necessarily use keys， but are a related and important class of cryptographic algorithms. They take input data （often an entire message）， and output a short fixed length hash， and do so as a one-way function. For good ones， （75） （two plaintexts which produce the same hash） are extremely difficult to find.
Message authentication codes （MACs） are much like cryptographic hash functions， except that a secret key is used to authenticate the hash value on receipt. These block an attack against plain hash functions.

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【信息安全工程师202011】【55】无线Wi-Fi网络加密方式中，安全性最好的是WPA-PSK/WPA2-PSK，其加密过程采用了TKIP和（55）。

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【信息安全工程师202011】【35】2001年11月26日，美国政府正式颁布AES为美国国家标准。AES算法的分组长度为128位，其可选的密钥长度不包括（35）。

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【信息安全工程师202011】【29】有线等效保密协议WEP是IEEE 802.11标准的一部分，其为了实现机密性采用的加密算法是（29）。

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