下列选项中，防范网络监听最有效的方法是（）。
A．安装防火墙
B．采用无线网络传输
C．数据加密
D．漏洞扫描
参考答案：C
解析：
本题考查网络攻击中网络监听的基础知识。
网络监听是主机的一种工作模式，在这种模式下，主机可以接收到本网段在同一条物理通道上传输的所有信息。使用网络监听工具可轻而易举地截取包括口令和账号在内的信息资料。采用数据加密的方式保护包括口令和账号在内的信息资料，使得即使获取密文后也无法解密成明文是对付网络监听的有效手段。
Passage Four
| It’s so difficult to follow the ups and downs of a 2-year-old．One moment he’s beaming and friendly; the next he’s sullen (愠怒的) and weepy, often for no apparent reason. These mood swings, however, are just part of growing up. They are signs of the emotional changes taking place as your child struggles to take control of actions, impulses, feelings and his body. At this age, your child wants to explore the world and seek adventure. As a result, he’ll spend most of his time testing limits, his own, yours and his environment’s. Unfortunately, he still lacks many of the skills required for the safe accomplishment of everything he needs to do, and he often will need you to protect him. When he oversteps a limit and is pulled back, he often reacts with anger and frustration, possibly with a temper tantrum (发脾气) or sullen rage. He may even strike back by hitting, biting or kicking. At this age, he doesn’t have much control over his emotional impulses, so his anger and frustration tend to erupt suddenly in the form of crying, hitting or screaming. It’s his only way of dealing with the difficult realities of life. He may even act out in ways that unintentionally harm himself or others. It’s all part of being 2. It’s not uncommon for toddlers to be angels when you’re not around, because they don’t trust other people enough to test their limits. But with you, your toddler will be willing to try things that may be dangerous or difficult, because he knows you’ll rescue him if he gets into trouble. Whatever protest pattern he has developed around the end of his first year will probably persist for some time. For instance, when you’re about to leave him with a sitter, he may become angry and throw a tantrum in anticipation of the separation. Or he may whimper, or whine and cling to you. or he could simply become subdued and silent. Whatever his behavior, try not to overreact by scolding or punishing him. The best tactic is to reassure him before you leave that you will be back and, when you return, to praise him for being so patient while you were gone. Take solace in the fact that separations should be much easier by the time he’s 3 years old. |
Which of the following is true
A．A-2-year-old doesn’t know how to express his anger and frustration.
B．A 2-year-old often intentionally harms himself or others.
C．A 2-year old depends on his parents to do everything new and challenging.
D．A 2-year-old trusts his parents more than other people.