对照ISO/OSI参考模型各个层中的网络安全服务,在传输层主要解决进程到进程间的加密,最常见的传输层安全技术有 (1) ;为了将低层安全服务进行抽象和屏蔽,最有效的一类做法是可以在传输层和应用层之间建立中间件层次实现通用的安全服务功能,通过定义统一的安全服务接口向应用层提供 (2) 安全服务。在数据链路层,可以采用 (3) 进行链路加密;在网络层可以采用 (4) 来处理信息内外网络边界流动和建立透明的安全加密信道;在物理层可以采用 (5) 加强通信线路的安全。 4()
A. 防窃听技术
B. 防火墙技术
C. 防病毒技术
D. IPsec
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Questions 11 to 18 are based on the conversation you have just heard.
Ask someone to help the man.
B. Give the man the note for his reference.
C. Lend the man her pencil and paper.
D. Feel sorry that she can’t help the man.
Passage OneQuestions 26 to 28 are based on the passage you have just heard.
A. It is the largest language family.
B. It was originated 4, 900 years ago.
C. It contains all the languages spoken in Europe.
D. Many of the present-day European and Indian languages are modern forms of it.
When should you get covered
In the following essay, each blank has four choices. Choose the best answer and write down on the answer sheet.A Web browser is simply a terminal emulator, designed to display text on a screen. The two essential differences between an ordinary terminal emulator and a Web browser are that the browser knows how to deal with (1) , and that it has a mechanism for (2) graphical files. Display text, display graphics, and (3) hyperlinks ——there’s 99 percent of the (4) value. That’s not to say that the manufacturers didn’t go all - out to attach a hyperactive efflorescence of useless capabilities onto their browsers. Remember when media channels in the browser were a big deal, instead of the clutter you can’t wait to delete from your favorites of bookmarks menu Remember when client -side Java applets were supposed to become the preferred (5) , for application development Remember frames and all their nasty side effects 3()
A. direct
B. navigate
C. indicate
D. go-on