问题 问答题 简答题

简述RSA算法。

答案

参考答案:

RSA公开密钥密码体制。所谓的公开密钥密码体制就是使用不同的加密密钥与解密密钥,是一种“由已知加密密钥推导出解密密钥在计算上是不可行的”密码体制。

在公开密钥密码体制中,加密密钥(即公开密钥)PK是公开信息,而解密密钥(即秘密密钥)SK是需要保密的。加密算法E和解密算法D也都是公开的。虽然秘密密钥SK是由公开密钥PK决定的,但却不能根据PK计算出SK。

阅读理解

阅读短文,根据要求完成下面各小题。

      In October of 2007, we launched Chang'e-1 successfully. It was the first lunar probe (月球探测器) in our

country. It is running well now. Every part of the lunar probe is working well. (1) On November 26, 2007, we

saw the first photo of the moon which was taken by Chang'e — 1. 

      "China has collected all the information in order to draw the first full map of the moon. We have almost

finished the map," said Sun Jiadong, chief designer of our country's lunar probe project. In the near future, we

will be able to see the clear map of the whole moon. We can learn more about the moon. 

      The launch of Chang'e — 1 was the first stage. Then there will be another two stages. They are the launch

of a lunar rover (月球车) for a soft landing and a second rover to collect stones from the moon for

study. (2) 中国计划第一辆月球车于2013年在月球着陆. Lots of Chinese universities and scientific institutes

plan to make their own rovers. The final rover will have the good points of all these rovers.

1. 把划线(1)处译为汉语。

                                                                                                        

2. China had got all the information to _______ the first full map of the moon. (用适当词填空)

3. How many stages are there in China's lunar probe problem? (回答问题)

                                                                                                        

4. 从文中找出与"can" 同义的词组。

                                                                                                        

5. 把划线(2)处译为英语。

                                                                                                        

单项选择题