Web Hosting Explained (part I)
In this article I will discuss the basics that are part of a web hosting company. There will be more articles following this one. My end goal of these articles is to give you enough information so you can decide what you need for your site and, maybe even more important, what you don’t need!
There are so many web hosts nowadays with so many different features and packages that it became really hard to judge whether a web host is good or not. It is not my intention to tell you which specific web host to pick. This is true for all types of products: if you know what’s out there and what your options are, making the right decisions will be easy.
What is web hosting?
Let’s start with my definition of web hosting:
The business of providing the storage, connectivity, and services necessary to serve files for a website.
This includes services like ftp access, e-mail, a database server and most important: a web server to serve files on the world wide web. A company that provides these services is called a web host. Most web hosting companies offer plans. A plan is a detailed description of the services offered by a web host. A plan might includes details like available web space, the maximum allowed data tranfer per month, the number of domains you are allowed to host on a plan and more. Most important, every plan has it’s own price. If you know what you don’t need, you will save money.
If you don’t understand some the terminology above, don’t worry! I will explain everything you need to know in this and following tutorials.
The basic concepts
If you want to be able to make the right choice you’ll need to learn a few terms and concepts about web hosting. I know, it’s boring so I’ll try to keep this short and entertaining.
The basic ingredients of a web hoster
To run a web hosting company, that company needs computers. These computers are usually called servers, because their main tasks are running server software. But there really is nothing magical about these servers. Most of the times they contain the same relatively cheap parts that are put into regular desktop pc’s. They usually have a very flat and long casing made of metal. They have no monitor, keyboard and mouse. This is all done to save space. These servers are mounted in large racks. You can put a lot of these flat servers on top of each other. Can you image the noise and heat these things can produce? It’s a lot! That’s one of the reasons why servers are placed in a so called data center.
A data center is well secured and build a bit higher than ground level. The air is conditioned very well to get rid of all the server heat and to keep the air dry. Dry air is very important, it increases the life time of electrical equipment. All the necessary internet connections, backup internet connections, power supply and backup power are provided inside the data center.
I hope you will have a general idea of the hardware side of web hosting. It might not be very important but it’s good to know the basics. It will increase your understanding of all the other stuff.
Now it is time to take a look at the most important server programs web hosters have on their servers.
The web server
This software program is used to serve files on the world wide web. The most common web server software is probably Apache but there are a lot more web servers. All have their own advantages and disadvantages. This is not something you have to worry about.
When you enter a URL that starts with http://, your browser will contact a web server at that address. The web server will look for the document you asked and serve it to your browser.
The ftp server
Ftp servers enable you to upload and download documents to the server. You can access the ftp server with an ftp client. You need to be able to put files like images and web pages on the server in order to make them publicly available on the web.
The mail server
Mail servers handle incoming and outgoing e-mail messages. The mail server waits all day for an email to come in and forward it to your inbox. It will also take an email from your email client (like Oulook) and send it to another address that you specified.
The DNS servers
A ‘Domain Name System’-server is used to resolve domain names to their corresponding tcp/ip address. When you enter a sites’ domain in your browser, the browser contacts the DNS server of your internet provider to get the ip-address of the server hosting that site. After recieving the ip-address your browser is able to contact the server directly and request the files you asked for.
You can compare this with the telephone system. Everyone has a number that’s connected to your name. On the internet, you enter the name instead of the number. With telephones, you enter the numbers directly. The DNS server is comparable with an automated telephone book, you say the name and milliseconds later you get a phone number! The DNS server is such an important player when it comes to actually finding your site on the web, that there as at least two of them. One main server and one or more backup servers. These servers are often hosted on different fysical locations. So when server 1 goes down for whatever reason (think of power problems, fires, flooding, terrorists..) the other servers will hopefully not be affected.
These are the most important server programs you will be using in the hosting business. DNS is not something you will manage yourself, but you will be dealing and interacting a lot with the web, mail and ftp server once your site is up and running.
This concludes part I of this introduction to the world of web hosting. In part II we will cover the different types of web hosting that are out there. We will talk about dedicated hosting, virtual servers and virtualization.