Google's Gmail system, which serves millions of customers around the world, shut down yesterday. Twitter, the micro - blogging service used by tens of millions of people, went off - line last month. It blamed the trouble on a malicious programmer in Russia who was trying to shut down the account of a user in neighboring Georgia. It is astonishing the local actions of a small number of programmers can bring an entire Interact service to its knees, but that have been the case. The Internet as it is set up now operates at three levels. The first is the servers that store data and content for use by customers. Google and other large companies keep massive server farms. These are well -protected from outside programmers by sophisticated software, but clearly that does not always work. The protection devices may fail more and more often as hackers get more skillful. The second part of the Internet is the" pipes" that carry data, video, e - mail messages, and text of websites from companies such as Google, Yahoo !, and Twitter, that make up Internet content and services to customers. Some of these" pipe" providers, specifically telecom and cable companies, are already complaining that the amount of data that they have to move is rising too rapidly for them to accommodate. Video files, which aye particularly large, have posed significant problems to cable companies. The last piece of the Internet is the end user, the companies and consumers who have the PCs. Perversely, these PCs are also the tools by which hackers build malicious code that they send out to compromise the effectiveness of the servers to destroy the data transport system which is at the core of the worldwide web's operations. The problem of online outages is as old as the internet itself, AOL's dial - up 56k service would go down regularly in the mid - 1990s. The company did not have enough modems to keep up with demand. The Internet for the last decade may not be the Internet for the future. The prophylactic software that was meant to protect the web is less effective. Like anything else that is used regularly whether it is a car, a light bulb, or a PC, the Internet is going to have to be upgraded more often now. It won't work every hour of every day anymore.
单选题
What is the main purpose of the first paragraph?
单选题
According to the passage, which description about internet is fight?
【正确答案】
C
【答案解析】考查关于特定事物的理解定位到文章原句The first is the servers that store data and content for use by customers；The second part of the Internet is the "pipes"．Some of these "pipe" providers，specifically telecom and cable companies；The last piece of the Internet is the end user．第一层是储存数据的服务器，第二层是数据通道，第三层是终端用户，选项A认为三层都是由网络公司拥有的服务器，是不正确的。选项C认为随着黑客技术的发展，要升级网络保护技术的要求越来越迫切，定位到文章原句The protection devices may fail more and more often as hackers get more skillful．由于黑客的技术越来越高，网路保护失效的可能性越来越大，可见选项C是符合文意的，故选择C。
单选题
According to the passage, what is main problem that cable companies face now7
【正确答案】
B
【答案解析】考查特定条件下发生的事情定位到文章原句Some of these "pipe" providers，are al ready complaining that the amount of data that they have to move is rising too rapidly for them to accommodate．一些数据通道提供商已经在抱怨数据的流量太大，而通道太小。选项B认为数据流量增长速度超过通道增长的速度，与文意是符合的。D项认为通道运营商有太多的数据要传输，从文章原句Some of these "pipe" providers，specifically telecom and cable companies，电信公司是数据通道的提供者，不是内容的提供者，故D不正确。
单选题
According to the passage, why the PCs can be the tools to destroy the internet system?
【正确答案】
C
【答案解析】考查具体事情发生的原因定位到文章原句these PCs are also the tools by which hackers build malicious code that they send out to compromise the effectiveness of the servers，个人电脑有时也会被黑客当作传输恶意代码的工具，而影响服务器的正常工作。选项C认为黑客可以利用个人电脑发出有破坏性的代码而降低服务器的功效，与文意相符，故选择C。
单选题
What can NOT be inferred from the passage?
【正确答案】
D
【答案解析】考查全篇大意选项A认为通常情况下对互联网的需求都大于能提供的互联网服务，定位到文章原句The problem of online outages is as old as the internet itself．可见互联网的老化问题一直伴随着互联网，故A是合文意的。选项B认为互联网和汽车一样，需要升级以满足对他更高的要求，Like anything else that is used regularly whether it is a car，the Internet is going to have to be upgraded more often now，故B是合文意的。选项C认为互联网偶尔会出现故障是正常的，定位到文章原句It won't work every hour of every day anymore，可见C是合文意的。选项D认为在50年代，美国对互联网的需求不大，定位到文章原句in the mid-1990s…The company did not have enough modems to keep up with demand．可见上世纪90年代中期，对互联网的需要是大于供应能力的。