For most people nowadays, using the internet involves accessing in­for­ma­tion or en­ter­tain­ment, viewing products and services, or using social media platforms to keep in touch with friends and ac­quain­tances. It may seem that visiting a webpage merely involves entering the URL in the address bar, but that’s just the start of a more com­pli­cat­ed process. In a split second the browser makes contact with globally dis­trib­uted web servers, requests stored data packages, and then assembles the webpage from the in­for­ma­tion contained in the packages. Read on to find out how this process works and which steps are taken.

From URL to IP address

The easiest way to access a website is to write the desired address into the address bar located in the browser. This address is known as a Uniform Resource Locator (URL), and every webpage can be reached with its own in­di­vid­ual URL (web address). A URL is made up of several sections; all of which have their own functions. Here is a generic example of a webpage URL:

Protocol Third-level domain Second-level domain Top-level domain (Path) (File)
http:// www. ex­am­ple­do­main .com /directory /index.html

The World Wide Web (WWW) is a system of elec­tron­i­cal­ly stored hypertext documents. The hypertext transfer protocol (HTTP) is used in the World Wide Web in order to transfer webpage data from the web server to the browser. In addition to HTTP, there’s also an encrypted version of the protocol: Hypertext Transfer Protocol Secure (HTTPS). The HTTP protocol header is followed by the hostname, which consists of a second-level and top-level domain (in this order). In the web, we usually see “www” as third-level domain, but there are other sub­do­mains. If a URL points to a specific directory or file, the relevant in­for­ma­tion will be placed after the hostname.

URLs are generally comprised of letters, meaning that people can easily remember them. Computers, on the other hand, work with com­bi­na­tions of numbers (known as IP addresses) to find a server on the internet. An ad­di­tion­al step is required in order to access content from the web browser. This step requires trans­lat­ing a webpage’s URL into the cor­re­spond­ing IP address. The task is carried out by DNS servers, which are re­spon­si­ble for managing the Domain Name System.

DNS server: a directory for IP addresses

When a web address is entered into the search bar of the browser, the browser looks for the requested domain in its cache. If it’s not there, it requests the operating system’s DNS server to find the required IP address. A DNS server is liable for the name res­o­lu­tion. The DNS server that is to be requested can be con­fig­ured in the operating system as well as in the router. Per default, the internet access provider sets the address of its own DNS server there. Since re­quest­ing the domain name system takes some time, the IP addresses of sites that have already been visited are usually stored in the operating system’s or the browser’s DNS cache. This cache keeps IP addresses at hand for future visits to the website. This lightens the load of the DNS server and speeds up the webpage’s loading time.

The router as a link between computer and server

The router is the interface between the internet and home network. It requests data from the internet and dis­trib­utes it to net­work­ing devices such as desktop computers, laptops, and tablets. The router is required as a link since the devices in the home network com­mu­ni­cate with each other using local IP addresses, while outwardly sharing the router’s public IP address. The network addresses are then trans­lat­ed with a process known as Network Address Trans­la­tion (NAT). With modern IPv6 internet con­nec­tions, trans­la­tions via NAT generally aren’t needed since every device in the network is allocated a public IP address.

Data exchange via HTTP

When the IP address of the chosen webpage is iden­ti­fied, the browser requests the relevant data for the page from the ap­pro­pri­ate web server. This request takes place via HTTP in the form of a data packet, which contains all the in­for­ma­tion the web server needs in order to deliver the webpage data. The browser com­mu­ni­cates the IP address of the chosen webpage, and provides in­for­ma­tion on the operating system, itself, and the device on which the webpage should be displayed. The router adds its own public IP address as sender and forwards the packet to the public internet. The web server processes the in­for­ma­tion and transmits an HTTP status code. Should the request be suc­cess­ful, the server sends a data packet to the web browser with all the in­for­ma­tion required for the page. If the server can’t find the webpage at the requested address, it either sends a 404 error code (webpage not found) or sends the visitor to the new URL via redirect if it’s known.

Be secure. Buy an SSL cer­tifi­cate.
  • Secures data transfers
  • Avoids browser warnings
  • Improves your Google ranking

Page rendering in web browsers

Incoming data packets from the internet are finally forwarded from the router to the computer on which the webpage is being accessed. The web browser then takes on the task of analyzing the data packets. Webpages generally comprise of HTML, CSS, and JavaScript files, whose lines of code contain detailed in­for­ma­tion about how the webpage should be presented. While HTML documents define the structure and controls of a webpage, the design in­for­ma­tion is specified in Cascading Style Sheets (CSS files). Elements that help user in­ter­ac­tion on the webpage are usually im­ple­ment­ed with JavaScript. The rendering engine of the web browser de­ter­mines how the code is in­ter­pret­ed. Webpages can have a different ap­pear­ance depending on the web browser used. Each browser has a cache in which data is tem­porar­i­ly stored when a webpage is accessed. This means that, when a webpage is re-visited, not all the data needs to be requested from the web server. The web browser simply retrieves the files that have changed since the last visit meaning that the website doesn’t take as long to access.

Go to Main Menu