java中英文翻译.docx

1、java中英文翻译Characteristics of LANsThe main Characteristics of a LAN include its throughput,delays,wiring type and distances,security,and reliability.We discuss these characteristics below.We then compare the characteristics of major LANs.ThroughputThe throughput is the average total transmission rate

2、when the LAN is heavily loaded by many nodes. In a shared LAN,the throughput is a fraction of the rate of the transmitters.This fraction is called the efficiency of the MAC protocl.For insyance,a network that uses a MAC protocol with an efficiency oh 65 percent and 10-Mbps transmitters has a through

3、put of 6.5 Mbps.These values are typical for a shared 10-Mbps Ethernet.The throughput of a token ring network and that of FDDI are close to their thransmission rate.LatencyThe latency is the time a packet takes froms its arrival at anetwork interface until it reaches the destination node.We explain

4、in Section 4.8that this latency is almost aiways less than a fraction of a second and is often much smaller.Wiring Type and DistanceSome LANs use twisted wire pairs,others use optical fibers,Older LANs and installations in special environments use coaxial cables.The maximum length of the connections

5、 depends on the LAN and on the techanology.Typical values are 100 m for twisted pairs and a few kilometers for multimode fibers.SecurityAnoptical fiber is more difficult to tap into than a twisted pair,which improves the “physical”security.However,eavesdroppers rarely need to tap directly into a lin

6、k to gain access to information.A more common attack is to use one of the computers attached on the LAN and configure it to read all the packets that travel on the network(this is called snooping).If sensitive pieces of information such as user passwords are transmitted in the clear(nonencrypted),th

7、en the eavesdropper obtains entry points into computers.As a rule,a switched LAN is more secure than a shared LAN because a computer on such a network sees only the packets intended for it.ReliabilityWe depend increasingly on networks.Accordingly,reliability becomes more essential.As we mentioned in

8、 the opening remarks of this chapter,FDDA is designed to survive a link or node failure.An Ethernet keeps on working when some of its nodes or links fail.Atoken ring network can be wired with bypass electronics to have a similar reliability.Network Devices TextThere are many types of media for the n

9、etwork, and each one has advantages and disadvantages. One of the disadvantages of the type of cable that we primarily use (CAT5 UTP) is cable length. The maximum length for UTP cable in a network is 100 meters (approximately 333 feet). If we need to extend our network beyond that limit, we must add

10、 a device to our network. This device is called a repeater.The term repeater comes from the early days of visual communication, when a man situated on a hill would repeat the signal to the person on the hill to his right. It also comes from telegraph, telephone, microwave, and optical communications

11、, all of which use repeaters to strengthen their signals over long distances, or else the signals will eventually fade or die out.The purpose of a repeater is regenerate and retime network signals at the bit level to allow them to travel a longer distance on the media. Watch out for the Four Repeate

12、r Rule for 10Mbps Ethernet, also known as the 5-4-3 Rule, when extending LAN segments. This rule states that you can connect five network segments end-to-end using four repeaters but only three segments can have hosts (computers) on them.The term repeater traditionally meant a single port “in” and a

13、 single port “out” device. But in common terminology today the term multiport repeater is often used as well. Repeaters are classified as Layer 1 devices in the OSI model, because they act only on the bit level and look at no other information. The symbol for repeaters is not standardized.The purpos

14、e of a hub is to regenerate and retime network signals. This is done at the bit level to a large number of hosts (e.g.4,8, or even 24) using a process known as concentration. You will notice that this definition is very similar to the repeaters, which is why a hub is also known as a multi-port repea

15、ter. The difference is the number of cables that connect to the device. Two reasons for using hubs are to create a central connection point for the wiring media, and increase the reliability of the network. The reliability of the network is increased by allowing any single cable to fail without disr

16、upting the entire network. This differs from the bus topology where having one cable fail will disrupt the entire network. Hubs are considered Layer 1 devices because they only regenerate the signal and broadcast it out all of their ports (network connections).E-commerce (Electronic Commerce, is abb

17、reviated as E-commerce) employs the way on the basis of the browser / server under the environment of Internets open network, realize consumers online shopping, online trade between the trade companies and a new kind of commercial operation modes paid by mails online. E-commerce on Internet can be d

18、ivided into three respects: Information service, trade and paying. The main content includes: Electronic market conditions advertisement; The electron is chosen and exchange of trade, electronic trade evidence; Paying by mails and settling account and online service after sale,etc. The main trade ty

19、pe is trade (C2C) of trade (B2B) and individual and man-to-man bet between enterprises and personal trade (B2C) and enterprise,etc. JSP (Java Server Page) is that dynamic Web based on that Java has nothing to do but with the platform develops technology, there is very high operational efficiency, de

20、velopment period is shorter, it is stronger to expand ability, have opening, step the platform, expandability and reusable characteristic. JAVABEAN is kind of a kind of Java, become through encapsulating and have a certain function or target of dealing with a certain business, can visit Bean and met

21、hod in JSP page Java code inside through inlaying. The online mobile phone store is a WEB application program based on that JSP/JAVABEAN technology sets up, divide into 2 parts of goods show of the front desk and sale, back-stage management, It is a kind of typical B2C e-commerce mode, realize the m

22、ain function of e-commerce.The electronic commerce 21 century economy grows engine,It not only in on microscopic affects the enterprise the management behavior and consumers expense behavior, moreover from on macroscopic will affect the international trade relations and the country future the compet

23、itive ability. This article in view of the electronic commerce in our country development present situation, has analyzed the question which exists in the development, proposed the corresponding solution and the suggestion, according to the physical resource, the financial resource and the talented

24、person develops our country electronic commerce, explores the China electronic commerce development path. Here nowadays develops the condition and the tendency two aspects from the electronic commerce connotation and the characteristic as well as the electronic commerce outlines the electronic comme

25、rce, by will have the direct-viewing understanding and the understanding to the electronic commerce. Makes the brief review afterwards to our country electronic commerce developing process, from aspect and so on environment condition, profession and local condition makes the multianalysis to our cou

26、ntry electronic commerce development present situation and indicates the electronic commerce in our country foreign trade status and the function, analyzes question which exists in the development, like lacks in the strategic plan and the policy support is insufficient, the corresponding legal laws

27、and regulations standard standard lag and so on. Finally aims at the question to propose the countermeasure and the suggestion, including government countermeasure and to enterprise, individual request and so on, and the forecast forecast electronic commerce development tendency and the direction, c

28、an play the certain impetus role by the time to our country electronic commerce health development .abstract this article with to know the circumstances of the matter the power in the outline electronic commerce right of privacy and its in the protection question foundation, discussed in the electro

29、nic commerce the right of privacy with to know the circumstances of the matter the power conflict question, then proposed the solution two conflict principle and the means. Key word the electronic commerce right of privacy knows the circumstances of the matter the power The electronic commerce is on

30、e kind of brand-new commercial mechanism which under the whole world economic integration background produces, has the high efficiency, boundless characteristic and so on, does not have time limit and low cost, receives the global various countries government and the enterprise widely takes, has bec

31、ome at the beginning of for the 21st century one of global economy biggest growth. The electronic commerce has had the huge impact to the present legal system, if this article is going to discuss the right of privacy and knows the circumstances of the matter the power always is a pair of opposition

32、legal science category, they have represented the different aspect spiritual benefit, but in information time electronic commerce, these two kind of rights conflict then is more prominent, therefore we have the necessity with to know the circumstances of the matter the power to in the electronic com

33、merce right of privacy to carry on the discussion, and attempts to seek the coordinated two conflict the means. In 1 electronic commerce privacy and its protection (1) in electronic commerce right of privacy and its content. The right of privacy is the natural person enjoys to its individual, individual information, the personal activit