【正文】 ze a system of Client/Server ask user study from the beginning, is hard to use. The interface of the user of Browser/Server is unified on browser, browser is easy to use , interface friendly, must not study use again other software, the use of a Lao Yong Yi that has solved user problem. Customer end detumescence: The customer end of Client/Server has the function that shows and handles data , as the requirement of customer end is a client puter it is fat very high. The customer of Browser/Server holds the access that not takes the responsibility for database again and the etc. task of plex data calculation, need it only show , the powerful role that has played server fully is so large to have reduced the requirement for customer end, customer end bee very thin . System is flexible: The 3 minutes of the system of Client/Server, in modular, have the part that need to change to want relation to the change of other modular, make system very difficult upgrading. The 3 minutes of the system of Browser/Server modular relative independence, in which a part of modular change, other modular does not get influence, it is very easy that system improve to bee, and can form the system with much better performance with the product of different manufacturer. Ensure systematic safety: In the system of Client/Server, directly join with database server because of client puter, user can very easily change the data on server, can not guarantee systematic safety. The system of Browser/Server has increased a level of Web server between client puter and database server , makes two not to be directly linked again, client puter can not be directly controled for database, prevent user efficiently invade illegally. The architecture of Browser/Server of threelayer has the advantage that a lot of traditional architectures of Client/Server does not have , and is close to have bined the technology of Inter/Intra, is that the tendency of technical development tends to , it application system tape into one brandnew develop times. From this us option the configuration of B/S the architecture that develops as system. what are C/S with B/S 5 For C/S with the technology of B/S develop change know , first,must make it clear that 3 problems. ( 1 ) What is the structure of C/S. C/S ( Client/Server ) structure, the server structure and client puter that all know well. It is software systematic architecture, through it can hold hardware environment fully using two advantage, realize task reasonable distribution to Client end and Server end , have reduced systematic munication expense. Now, the most systems of application software are the two levels of structure of the form of Client/Server , are developing to the Web application of distribution type since current software application is systematic, Web and the application of Client/Server can carry out same business handling , apply different modular to share logic assembly。對(duì)于一臺(tái)計(jì)算機(jī)來(lái)說(shuō)，它可以具有雙重功能，在某一時(shí)刻充當(dāng)服務(wù)器 ，而在另一時(shí)刻又成為客戶(hù)機(jī)。 在 Browser/Server 的系統(tǒng)中，用戶(hù)可以通過(guò)瀏覽器向分布在網(wǎng)絡(luò)上的許多服務(wù)器發(fā)出請(qǐng)求。它從根本上改變了傳統(tǒng)的二層 Client/Server 體系結(jié)構(gòu)的缺陷，它是應(yīng)用系統(tǒng)體系結(jié)構(gòu)中一次深刻的變革。 (1) 什么是 C/S 結(jié)構(gòu)。目前我院內(nèi)網(wǎng)（ Intra）、外網(wǎng)（ Inter）和北京東方清大公司“案件、辦公管理軟件”就是 B/S 結(jié)構(gòu)管理軟件，干警在局域網(wǎng)各工作站通過(guò) WWW 瀏覽器就能實(shí)現(xiàn)工作業(yè)務(wù)。一旦服務(wù)器程序被啟動(dòng)，就隨時(shí)等待響應(yīng)客戶(hù)程序發(fā)來(lái)的請(qǐng)求；客戶(hù)應(yīng)用程序運(yùn)行在用戶(hù)自己的電腦上，對(duì)應(yīng)于數(shù)據(jù)庫(kù)服務(wù)器，可稱(chēng)為客戶(hù)電腦，當(dāng)需要對(duì)數(shù)據(jù)庫(kù)中的數(shù)據(jù)進(jìn)行任何操作時(shí)，客戶(hù)程序就自動(dòng)地尋找服務(wù)器程序，并向其發(fā)出請(qǐng)求，服務(wù)器程序根據(jù)預(yù)定的規(guī)則作出應(yīng)答，送回結(jié)果，應(yīng)用服務(wù)器運(yùn)行數(shù)據(jù)負(fù)荷較輕。在這種結(jié)構(gòu)下，用戶(hù)工作界面是通過(guò) WWW 瀏覽器來(lái)實(shí)現(xiàn)，極少部分事務(wù)邏輯在前端（ Browser）實(shí)現(xiàn)，但是主要事務(wù)邏輯在服務(wù)器端（ Server）實(shí)現(xiàn)，形成所謂三層 3tier 結(jié)構(gòu)。Browser/Server 系統(tǒng)在客戶(hù)機(jī)與數(shù)據(jù)庫(kù)服務(wù)器之間增加了一層 Web 服務(wù)器，使 13 兩者不再直接相連，客戶(hù)機(jī)無(wú)法直接對(duì)數(shù)據(jù)庫(kù)操縱，有效地防止用戶(hù)的非法入侵。這種三層體系結(jié)構(gòu)如下圖所示。同時(shí)，由于把許多業(yè)務(wù)邏輯集中到了單一的應(yīng)用服務(wù)器上，應(yīng)用系統(tǒng)的維護(hù)工作也被集中到了一起，消除了傳統(tǒng) Client/Server結(jié)構(gòu)中軟件分發(fā)的問(wèn)題。網(wǎng)絡(luò)各站點(diǎn)主機(jī)上資源（硬件、軟件、數(shù)據(jù)）分步不均衡，在客戶(hù) /服務(wù)器結(jié)構(gòu)下，無(wú)資源的客戶(hù)機(jī)通過(guò)向有資源的服務(wù)器發(fā)出請(qǐng)求，并得到資源請(qǐng)求，從而適應(yīng)網(wǎng)絡(luò)中資源分布的不均衡性。 It is even in one time dialogue course, mutual role also exchanges probably. As in carry out file transmission , if be called as one side who offers file server, is called as one side who gets file customer, when using get or mget order since another node takes file, can think that what self use and it is client puter , is using put or mput order to another node dispatch file can again think the machine that used self is server. Multilayer customer / server structure Along with the development of enterprise application, recently, have again arisen a kind of new multilayer architecture, it applies customer end to divide into two minutes: Customer application and server apply. Customer application is the part of original customer application , is another and partial to have been transfered to server to apply. New customer application takes the responsibility for user interface and simple regular business logic and new server application resident core , changeable business logic. Therefore its structure has bee new ( Client application + Server application )/Server structure. Following picture shows: This kind of structure has solved traditional Client/Server can expand problem, have reduced customer end business logic , and have reduced the requirement of customer end for hardware. At the same time because of a lot of business logic concentrations have gone to unitary application server on, the maintenance work of application system had been also concentrated together, have eliminated the problem in the This kind of structure is called as the architecture of B/S. Browser/Server and browser / server hold the architecture of B/S. On essence, Browser/Server is also a kind of structure of Client/Server, it is a kind of from the traditional two levels of structural development of Client/Server e to the threelayer structural special case of Client/Server that applied on Web. In the system of Browser/Server, user can pass through browser to a lot of servers that spread on work to send request. The structure of Browser/Server is maximum to have simplified the work of cl