Câu hỏi:

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer.

The advent of the Internet may be one of the most important technological developments in recent years. Never before have so many people had access to so many different sources of information. For all of the Internet’s advantages, however, people are currently becoming aware of some of its drawbacks and are looking for creative solutions. Among the current problems, which include a general lack of reliability and numerous security concerns, the most crucial is speed.

First of all, the Internet has grown very quickly. In 1990, only a few academics had ever heard of the Internet. In 1996, over 50 million people used it. Every year, the number of people with access to the Internet doubles. The rapid growth has been a problem. The computer systems which run the Internet have not been able to keep up with the demand. Also, sometimes, a request for information must pass through many routing computers before the information can be obtained. A request for information made in Paris might have to go through computers in New York, Los Angeles and Tokyo in order to obtain the required information. Consequently, the service is often slow and unpredictable. Service also tends to be worse when the Internet is busiest - during the business day of the Western Hemisphere - which is also when companies need its service the most.

Some people are trying to harness the power of networked computers in such a way as to avoid this problem. In 1995, a group of American universities banded together to form what has come to be known as Internet II. Internet II is a smaller, more specialized system intended for academic use. Since it is more specialized, fewer users are allowed access. Consequently, the time required to receive information has decreased.

Businesses are beginning to explore a possible analogue to the Internet II. Many businesses are creating their own “Intranets”. These are systems that can only be used by the members of the same company. In theory, fewer users should translate into a faster system. Intranets are very useful for large national and international companies whose branches need to share information. Another benefit of an Intranet is an increased amount of security. Since only company employees have access to the information on the Intranet, their information is protected from competitors.

While there is little doubt that the Internet will eventually be a fast and reliable service, industry and the academic community have taken their own steps toward making more practical global networks.

According to the author, what is one reason why the Internet is sometimes slow?