AJAX Asynchronous JavaScript and XML

AJAX introduction  Ajax applications, look and act more like desktop applications. ex. writelywritely Ajax applications can add or retrieve new data for a page it is working with and the page will update immediately without reloading. ex. mapsmaps Classic modelAJAX model

Component technologies  DHTML ( Dynamic HTML )  XML (eXtensible Markup Language )  CSS ( Cascading stylesheets )  Document object model  JavaScript  XMLHttpRequest

Classic model & Ajax model

Classic & Ajax - example  Classic Classic Page 1 Http Request Page2  Ajax Ajax Page 1 Page 2

Classic web application model (synchronous)

Ajax web application model (asynchronous)

WHAT ’ S NEXT  Spending the time and money required to install applications on every computer. Ajax also could be useful for the growing number of Web applications for mobile devices.  Ajax may prove interesting to developers now, they may turn to versions of Flash and other technologies in the future.

Ajax 帶動另類資安威脅  由於採用 Ajax 技術將可創造更多的動態網頁， 也使得各種應用程式的增減更為容易，但若 該動態網頁有漏洞，將使得企業內應用系統 的弱點暴露在外。  日前有一個蠕蟲利用 Yahoo 郵件服務 Java Script 的漏洞，引發隱碼攻擊（ SQL Injection ）、跨站攻擊（ Cross Site Script ）以及 DoS （阻斷式服務攻擊）等。

攻擊方式  /winnt/system32/cmd.exe  /msadc/root.exe  ‘ or pwd like ‘ % ’  Ping 134.x.x.x – l size