Technology Selection
Think of web technologies as falling into one of the following categories:- GUI (presentation)
- Communication
- Middleware
- Data
CORBA, DCOM and enterprise Java Beans provide distributed objects communication.
CGI, ASP and Servlets are middleware, providing for server-side processing.
Communication
Typing script via a telnet session duplicates a browser request.MIME headers, specified in the HTTP header, designate the transported-file contents.
Ajax
AJAX is just XMLHttpRequest.HTTP Request
Search parameters are separated from the URL with a question mark (?). Each search and parameter set is separated by an ampersand (&). Search parameters are specified as "name/value pairs", separated by an equal sign (=). Spaces are replaced with a plus (+) sign. Non-alphanumeric characters are replaced with their hexadecimal equivalents, escaped with the percent sign (%).Encryption
Rather than distribute private decryption and encryption keys to trusted parties and cross your fingers, distribute your public key with full confidence that messages sent to you will only be readable by you.SSL (Secure Sockets Layer) an open, non-proprietary protocol, designed by Netscape, is the most common data transmission encryption methodology between web browsers and web servers (HTTP-S is the runner up).
Both Netscape and Microsoft have implemented SSL. The browser and SSL-server will do all the encryption work; your code remains the same.
Form submission
Web servers, typically, limit the number of characters they'll accept in a GET request. Never use GET for an operation that has "side effects” i.e. that actually does something.Middleware
The web server is the entry point to the Middleware Layer, which processes incoming requests, using (including networked) resources, available to the web server. Middleware uses network protocols to access distributed objects, provided by technologies such as DCOM (Microsoft), CORBA (Open Systems/C++) and RMI (Java).CGI is an "interface", bridging the web server to the back end resources; however, CGI does not define the implementation.
Server-side Includes (SSI)
Server-side Includes API’s extend operating-system functionality for the web application server. Cold Fusion and Net Objects designed custom web servers with incredible SSI functionality, providing dynamic web-page capabilities. Cold Fusion Web Server, perhaps the best-known SSI-based application server, offers over 70 custom "CFML" tags.ASP (Active Server Pages)
ASP is an IIS web server extension - to code custom-tags in JavaScript (JScript) or VBScript; these tags can be interpreted by IIS before the pages are sent out. An ASP page is a text file with an .asp extension, containing HTML and scripting (e.g.. Vbscript). Unlike SSI, ASP has a robust object set to do serious programming. ASP also gives the ability to instantiate server-side resources (i.e. any COM component a.k.a. ActiveX for web use). Apache has a MOD_ASP module - to code ASP pages on Apache web servers. Third party vendors also provide ASP functionality for non-IIS servers.Web Services
Web services are an alternative to CGI, SSI and ASP/COM technologies.Java Servlets
Since Java was designed for network use, implementing a web service involves creating client sockets and then processing the socket data. Java Servlets are Java server services, embedded through the web server ... like server-side applets. The web server will load and execute Java Servlets, as a browser would an applet. Since they run on the server side, security and communications restrictions, typical of Java applet programming, do not apply to Java Servlets.Java Servlet-aware web application servers include Java Web Server (JWS), Apache (using JServ) and O'Reilly WebSite. Third party add-ons, which handle web server servlets include ServletExec and JRun.
REST
… requests are URLs with encoded parameters.SOAP
… XML transmitted to and received from a SOAP server via HTTP.SOAP requests accept more parameters than GET requests. Several SOAP requests may be bundled within one XML document request. The SOAP server is specified in the WSDL file.
An example, handling SOAP requests via PHP, is here: https://www6.software.ibm.com/developerworks/education/os-amazon1/section4.html
Presentation
The most popular style sheet standards are CSS (Cascading Style Sheets) and XSL (eXtensible Style Sheet Language); CSS has the market share.When Microsoft Word documents are saved as HTML web documents, Title and Heading 1 will not wrap, properly, around floating boxes. To fix, modify the Title and Heading 1 Format -> Frame setting from “Around” (the right-side box) to “None” (the left-side text box).
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