How can the HTTP Server Perform?

The HTTP protocol is the most used protocol in use inside the TCP/IP arena. Every day huge amounts of people use it inside their internet sessions, when they browse the net.

In this article My goal is to explain how this server works for many who need or want to know this mechanism.

(The HTTP server has to be installed in computers in which hold html pages for your browsers to display).

The HTTP server unwraps a 'listening' socket for incoming connection to it. When a web browser (the HTTP server's client) directs a request, it processes the obtain and sends back a remedy. The browser request seems like this:

"GET /index. html HTTP/1. 1

Sponsor: qms. siptele. com

User-Agent: Mozilla/5. 0 (Windows; You; Windows NT 6. 0; en-US; motorhome: 1. 9. 2. 10) Firefox/3. 6. 10

Acknowledge: image/png, image/*; q=0. 8, */*; q=0. 5

Accept-Language: en-us, en; q=0. 5

Accept-Encoding: gzip, deflate

Accept-Charset: ISO-8859-1, utf-8; q=0. 7, *; q=0. 7

Keep-Alive: 115

Relationship: keep-alive

Referer: "

The HTTP server searches for a file name "index. html" in the HTTP main directory and sends that back if exists or inform the file does not is out there - error code "404" as many of us noted.

The request includes several lines with value:

The "Host" line shows the HTTP server whose host is at reference. This field allows the HTTP server to deal with several hosts (or domains) in a server. It just sees this value and consider the proper root directory because of this host.

The "User-Agent" tells the particular server which browser is at use. In our case it really is "Firefox" browser. This field does not have any special importance, it just we can get statistics about the browsers percentage used.

The accept fields inform the server in regards to the browser capabilities. The server attempts to be able to send back content the browser can handle.

The "keep alive" tells the server the browser wants to utilize the current socket for 115 times for requests/responses.

The "Referrer" field is the main information for Internet internet marketers. It tells the server where page the browser originated in. This information is logged and informs us things such as:

a. What search phrases where found in the search engine (like Google) to get us.

b. Which advertisement of ours gets visited.

c. Which article/page points to your site generated this check out.

This information is precious. It tells us just how are marketing efforts carrying out. If we run ads browsing engines for example we could know which ad will be performing better then other folks, and focus on that.

The first HTTP servers where able to locating files and sending these to the browsers. Later on the necessity to access databases arouse and taken to the creation of "CGI" (Common Entry Interface) programs. The CGI is simply a native program that runs from the HTTP server in a particular process environment, gets some request parameters from your server and processes that.

After the processing it returns the data to the HTTP server which sends it returning to the browser.

Having a native program running around the server opens many options for the programmer. He can accessibility and process information inside databases, create dynamic behavior with the system and open completely new ways of system features.

Opening the system furthermore increased the vulnerability with the computer to hacking...

Right after several penetration incidents, a fresh restricting set of rules are already developed for the server. The server now has privileges of your restricted account and party, so it could only run inside the predefine directories allocated with it, and not access the complete system. Having restricted account also means that an intruder gaining shell usage of the server (after piling the HTTP server) will never be able to see and also utilize system information to get control over the personal computer itself.

There was a demand for owning a script language to simplicity the developing time. This demand was responded to by company called "Zend" in which developed a scripting terminology called "PHP" which represents "Personal Home Page". Once i say "scripting language" After all a language that will be interpreted line by series at execution time. Such languages take more hours to parse and carry out compatible to native programs (that should just be run), but the rapid boost in computer performance helps it be irrelevant.

PHP gained a huge user-base and is probably the top scripting languages used today. To run that, the HTTP server needs a PHP interpreter to be able to process it. When the HTTP server requested to deal with a PHP program that run the PHP interpreter being a CGI program, and this interpreter provides the PHP script and techniques it.

A new mechanism was invented to help keep information in the web browser, which are called "cookies". Cookies are short level of information sent from the particular HTTP server and kept from the browser. The browser keeps these records and sends it each and every time it accesses the HTTP server. This information allows keeping state information for some time. The information often includes username and session -id so people need not fill their username and password each and every time they access the HTTP server. This is one way Gmail "remembers" the consumer and session that users have and invite them to open the appropriate Email page without seeking credentials every time.

These days the HTTP server have become sophisticated. Web 2. 0 allows sending many requests for the browser and get responses without necessity to refresh the complete screen. This makes it an easy task to process information inside the particular page without affecting the complete page. This makes it easy and interactive to change information quickly in web sites like Facebook.

I have explained the following the operation and evolvement with the HTTP server. This description should give bird-eye overview in regards to the way an HTTP server works and invite programmers to understand the causes of creating things while they are.

Owner of Woodstone - Home of Servers Alive Network Monitoring application