Web pages are a collection of data, including images, text files, hyperlinks, database files etc., all located on some computer (also known as server space) on the Internet. A web server is dedicated software that runs on the server-side. When any user requests their web browser to run any web page, the webserver places all the data materials together into an organized web page and forwards them back to the web browser with the help of the Internet. Therefore, we can conclude that: -
A web server is a dedicated computer responsible for running websites sitting out on those computers somewhere on the Internet. They are specialized programs that circulate web pages as summoned by the user. The primary objective of any web server is to collect, process and provide web pages to the users.
This intercommunication of a web server with a web browser is done with the help of a protocol named HTTP (Hypertext Transfer Protocol). These stored web pages mostly use static content, containing HTML documents, images, style sheets, text files, etc. However, web servers can serve static as well as dynamic contents. Web Servers also assists in emailing services and storing files. Therefore it also uses SMTP (Simple Mail Transfer Protocol) and FTP (File Transfer Protocol) protocols to support the respective services. Web servers are mainly used in web hosting or hosting the website's data and running web-based applications.
The hardware of the web servers are connected to the Internet that manages the data exchange facility within different connected devices. In contrast, the software of web server software is responsible for controlling how a user accesses delivered files. Typically, web server management is an ideal example of the client/server model. Therefore, it is compulsory for all computers that host websites (whether with state or dynamic web page content) to have web server software.
How do web servers work?
The term web server can denote server hardware or server software, or in most cases, both hardware and software might be working together.
- On the software side, a web server includes server software accessed through website domain names. It controls how web users access the web files and ensures the supply of website content to the end-user. The web server contains several components, including an HTTP server.
Whenever any web browser, such as Google Chrome, Microsoft Edge or Firefox, requests for a web page hosted on a web server, the browser will process the request forward with the help of HTTP. At the server end, when it receives the request, the HTTP server will accept the request and immediately start looking for the requested data and forwards it back to the web browser via HTTP.
Let's discover the step-by-step process of what happens whenever a web browser approaches the web server and requests a web file or file. Follow the below steps:
- First, any web user is required to type the URL of the web page in the address bar of your web browser.
- With the help of the URL, your web browser will fetch the IP address of your domain name either by converting the URL via DNS (Domain Name System) or by looking for the IP in cache memory. The IP address will direct your browser to the web server.
- After making the connection, the web browser will request for the web page from the web server with the help of an HTTP request.
- As soon as the web server receives this request, it immediately responds by sending back the requested page or file to the web browser HTTP.
- If the web page requested by the browser does not exist or if there occurs some error in the process, the web server will return an error message.
- If there occurs no error, the browser will successfully display the webpage.
NOTE: A single web server can host multiple domains as well.
Examples of web server uses
Web servers are mostly used for:
- sending and receiving mails on Internet by using SMTP (Simple Mail transfer Protocol);
- fetching requests for File Transfer Protocol (FTP) files; and
- designing, developing, and publishing websites.
Static web servers vs. Dynamic web servers
A web server can be used to store, process or deliver either static or dynamic web pages. Let's understands the definition of static and dynamic web servers with the help of their difference table given below:
||Static Web Servers
||Dynamic Web Servers
||Static web servers refer to the servers, which serve only the static content i.e., the content is fixed and being shown as it is.
||Dynamic web servers refer to the servers where the content of the page can be updated and altered.
||A static web server includes a computer and the HTTP (Hyper Text Transfer Protocol) software.
||A dynamic web server also includes a computer with plenty of other software, unlike an application server and database model.
||It is called static; the web pages content won't change unless the user manually changes it, and the server will deliver web files as is to the web browser.
||It is called dynamic because the application server is used to update the web pages files at the server-side, and due to which, it can change on every call requested by the web browser.
||Static web servers take less time to load the data.
||The Dynamic web server can only produce the data when it is requested from the database. Therefore, it is time consuming and more complicated when compared to static web servers.
Web server software available in the market
Though there are various web servers found in today's market, but the commonly used one are as follows:
||Web Server Description
||Apache HTTP Server
This web server is developed by Apache Software Foundation. It is an open-source, accessible web server available for almost all operating systems, including Windows, MACOS, Linus, FreeBSD, etc. Apache is one of the most popular web servers used around the globe.
||Microsoft Internet Information Services (IIS)
IIS is a high-performance web server that is developed by Microsoft only for Microsoft platforms. This webs server is tightly integrated with Microsoft operating system; therefore, it is not open-sourced.
Nginx is an open-source web server commonly used by administrators as it supports light resource application and scalability.
Lighttpd, also known as lighty, is a free, open-source web server with the FreeBSD operating system. This web server is fast, secure and consumes much less CPU power. It can also run on the commonly used operating system, unlike Windows, Mac OS X, Linus.
||Sun Java System Web Server
Sun Java is a free web server developed by Sun Microsystems well equipped for a medium and large website that can run on Windows, Linux and Unix. Moreover, this web server supports several languages, scripts and technologies essential for Web 2.0, unlike JSP, Java Servlets, PHP, Python, HTML, etc. Though Sun Java is free, it is not an open-source web server.
Web server security Methods
Though there are various security techniques available in the market that a user can implement to have a safe web server experience, below given are some examples of security practices that can include processes:
- A reverse proxy is a proxy server that is accessible to the clients, therefore hiding the internal server. It acts as an intermediary as wherever any user makes requests to the web server for any data or file, the proxy server seizes those requests and then communicates with the webserver.
- Access restriction is a technique that limits the web host's access to infrastructure machines or using Secure Socket Shell (SSH);
- Keeping web servers mended and updated, as it benefits to ensure the web server isn't vulnerable to exposures;
- Network monitoring is a security practice that ensures that no unauthorized activity is going on the web server; and
- Using a firewall and SSL safeguards the web server as firewalls can supervise HTTP request traffic while a Secure Sockets Layer (SSL) supports securing the data.