2016下半年信息安全工程师试题 - 图文(5)

64、以下关于网络流量监控的叙述中，不正确的是（）

A、流量检测中所检测的流量通常采集自主机节点、服务器、路由器接口和路径等 B、数据采集探针是专门用于获取网络链路流量的硬件设备 C、流量监控能够有效实现对敏感数据的过滤

D、网络流量监控分析的基础是协议行为解析技术 参考答案：C

65、两个密钥三重DES加密：C=CK1[DK2[EK1[P]]],K1≠K2，其中有效的密钥为（） A、56 B、128 C、168 D、112 参考答案：C

66、设在RSA的公钥密码体制中，公钥为（e，n）=（13,35），则私钥为（） A、11 B、13 C、15 D、17 参考答案：C

67、杂凑函数SHAI的输入分组长度为（）比特 A、128 B、258 C、512 D、1024 参考答案：C

68、AES结构由以下4个不同的模块组成，其中（）是非线性模块 A、字节代换 B、行移位 C、列混淆

D、轮密钥加 参考答案：A

69、67mod119的逆元是（） A、52 B、67 C、16 D、19 参考答案：C

70、在DES算法中，需要进行16轮加密，每一轮的子密钥长度为（） A、16 B、32 C、48 D、64 参考答案：C

（71）is the science of hiding information。Whereas the goal of cryptography is to make data unreadable by a third party。the goal of steganography is to hide the data from a third party。In this article,I will discuss what steganography is,what purposes it serves,and will provide an example using available software。

There are a large number of steganographic（2）that most of us are familiar with(especially if you watch a lot of spy movies),ranging from invisible ink and microdots to secreting a hidden message in the second letter of each word of a large body of text and spread spectrum radio communication。With computers and networks,there are many other ways of hiding informations,such as:

Covert channels(c,g,Loki and some distributed denial-of-service tools use the Internet Control（3）Protocol,or ICMP,as the communication channel between the“bad guy”and a compromicyed system) Hidden text within Web pages

Hiding files in“plain sight”(c,g，what better place to“hide”a file than with an important sounding name in the c:\\winnt system32 directory)

Null ciphers(c,g,using the first letter of each word to form a hidden message in an otherwise innocuous text)

steganography today,however,is significantly more（4）than the example about suggest,allowing a user to hide large amounts of information within image and audio。These forms of steganography often are used in conjunction with cryptography so the information is double protected;first it is encrypted and then hidden so that an advertisement first。find the information(an often difficult task in and of itself)and the decrypted it。

The simplest approach to hiding data within an image file is called（5）signature insertion。In this method ,we can take the binary representation of the hidden data and the bit of each byte within the covert image。If we are using 24-bit color the amount and will be minimum and indiscriminate to the human eye。 （71）A、Cryptography B、Geography C、Stenography D、Steganography （72）A、methods B、software