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The Internet is a global network that connects other computer networks, together with software and protocols for controlling the movement of data. The Internet, often referred to as "the Net", was initiated in 1969 by a group of universities and private research groups funded by the US Department of Defense. It now covers almost every country in the world. Its organization is informal and deliberately nonpolitical; its controllers tend to concentrate on technical aspects rather than on administrative control. The Internet offers users a number of basic services including data transfer, electronic mail, and the ability to access information in remote databases. A notable feature is the existence of user groups, which allow people to exchange information and debate specific subjects of interest. In addition, there are a number of high-level services. For example, MBONE allows the transmission of messages to more than one destination. It is used in videoconferencing. The World Wide Web, known as "the Web", is another high level Internet service, developed in the 1990s in Geneva. It is a service for distributing multimedia information, including graphics, pictures, sounds, and video as well as text. A feature of the World Wide Web is that it allows links to other related documents elsewhere on the Internet. Documents for publication on the Web are presented in a form known as HTML (hypertext mark up language). This allows a specification of the page layout and typography as it will appear on the screen. It also allows the inclusion of active links to other documents. Generally, these appear on the screen display as highlighted text or as additional icons. Typically, the user can use a mouse to "click" on one of these points to load and view a related document. Many commercial and public organizations now have their own Web site (specified by an address code) and publish a "home page", giving information about the organization. Up to the mid-1990s, the major users of the Internet were academic and research or ganizations. This has begun to change rapidly with individual home users linking in through commercial access providers and with a growing interest by companies in using the Internet for publicity, sales, and as a medium for electronic publishing. At the same time, there are problems with the flow of information across national borders, bringing in debates about copyright protection, data protection, the publication of pornography, and ultimately political control and censorship. It can be inferred that the development of HTML prepared the way for ______.

A. even farther information transfer
B. online commercial promotions
C. academic uses
D. distributing multimedia information

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Publication of this survey had originally been intended to coincide with the annual meetings of the World Bank and the International Monetary Fund, scheduled for September 29th-30th in Washington, D.C. Those meetings, and the big anti-globalization pro- tests that had been planned to accompany them, were among the least significant casualties of the terrorist atrocities of September 11th. You might have thought that the anti-capitalist protesters, after contemplating those horrors and their aftermath, would be regretting more than just the loss of a venue for their marches. Many are, no doubt. But judging by the response of some of their leaders and many of the activists (if Internet chat rooms are any guide), grief is not always the prevailing mood. Some anti-globalists have found a kind of consolation even a cause of satisfaction, in these terrible events--that of having been as they see it, proved right. To its fiercest critics, globalization, the march of international capitalism, is a force for oppression, exploitation and injustice. The rage that drove the terrorists to commit their obscene crime was in part, it is argued, a response to that. At the very least, it is suggested, terrorism thrives on poverty and international capitalism, the protesters say, thrives on poverty too. These may be extreme positions, but the minority that holds them is not tiny, by any means. Far more important, the anti-globalists have lately drawn tacit support if nothing else, reluctance to condemn--from a broad range of public opinion. As a result, they have been, and are likely to remain, politically influential. At a time such as this, sorting through issues of political economy may seem very far removed from what matters. In one sense, it is. But when many in the West are contemplating their future, with new foreboding, it is important to understand why the skeptics are wrong; why economic integration is a force for good; and why globalization, far from being the greatest cause of poverty, is its only feasible cure. Undeniably, popular support for that view is lacking. In the developed economies, support for further trade liberalization is uncertain; in some countries, voters are down- right hostile to it. Starting a new round of global trade talks this year will be struggle, and seeing it through to a useful conclusion will be. The institutions that in most people’s eyes represent the global economy--the IMF, the World Bank and the World Trade Organization are reviled far more widely than they are admired; the best they can expect from opinion at large is grudging acceptance. Governments, meanwhile, are accused of bowing down to business, globalization leaves them no choice. Private capital moves across the planet unchecked. Wherever it goes, it bleeds democracy of content and puts "profits before people". After September 11th, what may NOT be the response of the anti-capitalist protesters

A. Some of them may see the attack as something right.
B. Some anti-globalists have found a kind of consolation, even a cause of satisfaction, in these terrible events.
C. Grief will be the mood of some of them.
D. All the anti-capitalist protesters, after contemplating those horrors and their aftermath, would be regretting more than just the loss of venue for their marches.

在一个宏中可以包含多个操作,在运行宏时将按 【8】 的顺序来运行这些操作。

In the past few decades, remarkable findings have been made in ethology, the study of animal social behavior. Earlier scientists had (21) that nonhuman social life was almost totally instinctive or fixed by genetics. Much more careful observation has shown that (22) variation occurs among the social ties of most species, showing that [earning is a part of social life. That is, the (23) are not solely fixed by the genes. (24) , the learning that occurs is often at an early age in a process that is called imprinting. Imprinting is clearly (25) instinctive, but it is not quite like the learning of humans, it is something in between the two. An illustration best (26) the nature of imprinting. Once, biologists thought that ducklings followed the mother duck because of instincts. Now we know that. shortly (27) they hatch, ducklings fix (28) any object about the size of a duck and will henceforth follow it. So ducklings may follow a basketball or a briefcase if these are (29) for the mother duck at the time when imprinting occurs. Thus, social ties can be considerably (30) , even ones that have a considerable base (31) by genetics. Even among the social insects something like imprinting (32) influence social behavior. For example, biologists once thought bees communicated with others purely (33) instinct. But, in examining a "dance" that bees do to indicate the distance and direction of a pollen source, observers found that bees raised in isolation could not communicate effectively. At a higher level, the genetic base seems to be much more for an all-purpose learning rather than the more specific responses of imprinting. Chimpanzees, for instance, generally (34) very good mother but Jane Goodall reports that some chimps carry the infant. upside down or (35) fail to nurture the young.

A. not
B. only
C. but
D. solely

While hackers with motives make headlines, they represent less than 20% of all net- work security breaches. More common are instances of authorized users accidentally winding up where they should not be and inadvertently deleting or changing data. However, the Internet introduces another concern: some Internet surfers are bound to go where they have no business and, in so doing, threaten to wipe out data to which they should not have access. Before picking a firewall, companies need to adopt security policies. A security policy states who or what is allowed to connect to whom or what. You can group all users by department or classification. The better firewall products let you drag and drop groups in a graphical user interface (GUI) environment to define network security easily. Two methods are most often used together to establish an Internet firewall. They are application and circuit gateways, as well as packet filtering. With application and circuit gateways, all packets are addressed to a user-level application on a gate-way that relays packets between two points. With most application gateways, additional packet-filter machines are required to control and screen traffic between the gateway and the networks. A typical configuration includes two routers. With a bastion host that serves as the application gateway sitting between them. A drawback to application and circuit gateways is that they slow network performance. This is because each packet must be copied and processed at least twice by all the communication layers. Packet-filter gateways, which act as routers between two nets, are less secure than application gateways but more efficient. They are transparent to many protocols and applications, and they require no changes in client applications, no specific application management or installation, and no extra hardware. Using a single, unified packet-filter engine, all net traffic is processed and then for- warded or blocked from a single point of control. However, most packet filters are state- less, understand only low-level protocols, and are difficult to configure and verity. In addition, they lack audit mechanisms. Some packet filters are implemented inside routers, limiting computing power and filtering capabilities. Others are implemented as s9ftware packages that filter the packets in application-layer processes, an inefficient approach that requires multiple data copies, expensive delays and context switches and delivers lower throughput. So what’s a network administrator to do Some vendors are developing firewalls that overcome many of these problems and combine the advantages of application gateways and packet filtering. These efficient, protocol-independent, secure firewall engines are capable of application-level security, user authentication, unified support, and handling of all protocols, auditing and altering. They are transparent to users and to system setup, and include a GUI for simple and flexible system management and configuration. According to what you have read, the author’s probable preference will he ______.

A. walling for the coming of better firewall products,
B. finding a combination of both application gateway and packet filtering approach
C. meeting demands of every type with better products
D. implementing one better approach in the adoption of a firewall solution

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