81、Which of the following is an example of a passive attack initiated through the Internet?
A、Traffic analysis
B、Masqueradin***enial of service
D、E-mail spoofing
ANSWER: A
NOTE: Internet security threats/vulnerabilities are divided into passive and active attacks. Examples of passive attacks include network analysis, eavesdropping and traffic analysis. Active attacks include brute force attacks, masquerading, packet replay, message modification, unauthorized access through the Internet or web-based services, denial-of-service attacks, dial-in penetration attacks, e-mail bombing and spamming, and e-mail spoofing.
81,下列哪一项是透过互联网发起被动攻击的实例？
A、流量分析
B、伪装
C、拒绝服务
D、电子邮件欺骗
互联网安全威胁/脆弱性分为被动和主动攻击。被动攻击的例子，包括网络分析，窃听和流量分析。主动攻击，包括暴力攻击，伪装，包重放，修改信息，透过互联网或基于Web的服务的未经授权的访问，拒绝服务攻击，拨号渗透攻击，电子邮件轰炸和垃圾邮件，和电子邮件欺骗。