By Brendan Fitzpatrick
To simplify the discussion for non-technical people I won’t attempt to dig into such topics as networking, switching, DNS etc. Simplified, the Internet is a very big network of devices across the globe with millions of computers and servers connected by network devices. Network devices route traffic to it’s proper destination upon request for various types of communication protocols (ie. video streaming, file transfer, web content etc.).
There are various forms of communication protocols which I’ll briefly touch upon here. The most common protocol is HTTP (Hyper Text Transfer Protocol) and HTTPS (Hyper Text Transer Protocol Secure) which is what a browser communicates with to a server (aka web server) – when you go to a web page in a browser the URL will start with http:// for public connections or https:// for secure connections, the ‘s’ in https:// indicating if the connection is secure or not. Think of a protocol as a language (set of requests and responses) that is used between 2 devices to communicate. Here are some other protocols commonly used over the internet but are lower level protocols (often used behind the scene of a process not obvious to the end user compared to HTTP/S)
FTP – file transfer protocol (for transferring files)
SFTP – secure file transfer protocol (for transferring files over encrypted communications)
SNMP – simple network mail protocol (for email)
Question: I know that the internet is a large black box where lots of people can do lot’s of things but how does it really work in simple terms?
Answer: If you think of the Internet as similar to a complicated phone system (many devices connected via wires, fiber optic or wireless and network switches), just like your phone number – your PC has a unique identification called your IP Address (Internet Protocol Address). Every device on the Internet including URL’s (such as mywebsite.com) has a unique IP Address associated with it, this is how the network devices know to connect your computer to where it wants to go.
A URL (Uniform Resource Locator) is a virtual name (domain name) assigned to an IP Address to make it easier for users to remember what to type in their browser.. isn’t it much easier to remember to go to http://google.com than it is to go to http://126.96.36.199? Google has 1000’s of servers each having a unique IP Address. Sometimes their servers (such as IP Address 188.8.131.52) will be taken out of service for maintenance so by using a URL you never need to worry if they take a server down, the URL translation is smart enough to know which IP Address on the Internet you want to go to (Lookup DNS for more information). It’s like having a phone number to an individual vs. to a 24×7 helpdesk with dozens of people waiting to pick up the phone. You are virtually guaranteed to have someone pick up the hotline number compared to hoping that someone is near their phone to pick up.
Hopefully I haven’t confused you yet. Now that you have a basic understanding of the basic concepts of how computers communicate with each other, the rest is simply information scattered across all the computers on the internet that can now be shared rather easily via the protocols already mentioned. For example, a file from a remote computer can be downloaded to your machine using the FTP protocol, all you need is a user ID and password that is setup on that remote computer. A browser is nothing more than a file transfer implementation but instead of downloading a file to your computer using FTP it simply GETS a file using the HTTP protocol and displays the file contents in your browser while reformatting it using the HTML tags within that file. Many websites are public so that you don’t need a user ID and password to access their files (ie. their homepage).