Servers:

The function of a server is to process the requests and demands of the client and route the information to the user. Depending on the clients request different types of servers may be called upon to retrieve and deliver the information. A web server is a computer that uses the HTTP protocol to send web pages to a client's computer when the client requests them. A print server operates on a local area network and manages one or more printers and print files sent by the client computer. Network servers manage the traffic of information being requested and received. A file server stores and retrieves files.

Since server co-location revolves around the use of the internet, an in-depth look into the function of a web server. The purpose of the web server is to store and exchange information with other machines. This function requires the work of two parties; a client, which requests the information, and a server which stores it. Each of these requires a piece of software to negotiate the exchange of data.

The function of a web server is complex as it involves the exchange of information between clients and servers with numerous application possibilities. In the case of the client, a browser such as Netscape or Explorer is used; however, the server end of the operation is a little more complicated as there are many software options available. The type of server software you are capable of using depends on the operating system chosen for the server; for instance, Microsoft Internet Information Server is an application compatible with Windows NT while Unix users often use Apache Web Server.

The basic exchange between the client machine and the web server can be explained in few easy to follow steps. First, the client's browser dissects the URL into a number of parts including address, pathname, and protocol. Then a Domain Name Server (DNS) translates the domain name the user entered into its IP address using a numeric combination that represents the site's true internet address. The browser then determines which protocol or language should be used to process the information; for example, FTP and HTTP. The server then sends a request to the web server to retrieve the address it has been given. The web server responds to the browser's request by verifying that the address given is legitimate, finds the necessary files, runs the appropriate scripts, if necessary exchanges cookies, and sends the results back to the clients via the browser. The browser then translates the data it has been given and displays the information to the user.

A web server is also responsible for many other tasks other than simply translating and delivering the data it's fed. A web server also distinguishes between various error and data types and between various elements on a web page such as GIF files, JPEG files and audio files. Depending on the site, a web server may also be required to perform additional tasks including logging statistics, security and encryption, serving images from other sites, generating dynamic content and managing e-commerce functions. Knowing the complexity and functions of a web server gives you a new appreciation for all the work that goes into delivering a single page of content.