Web Hosting Definitions

I will be updating this in the next few weeks. If you have some that I missed, please add them in the thread and I will add them to the main post.

95th Percentile – This is a method used by some web hosts where they will only bill you for 95% of your bandwidth usage. The reasoning for this is that your top 5% are spikes that are not usually part of normal operations. This method is calculated by taking the average bandwidth used in 5min intervals and then taking only 95% of the usage for that 5minutes.

Bandwidth – The amount of data that can be transferred in a fixed amount of time. This can be expressed in Gigabytes per month, or throughput amounts like Mbs. As a rule of thumb, 1mbs of bandwidth equates 300gb per month. Meaning, if you consitantly use 1mbs, you will wind up using 300gb of bandwidth (or sometimes known as transfer) per month. In terms of your web hosting account, everything from uploading files, to retrieving email, to actually getting hits on your website will use bandwidth.

Co-location – This term means that you are co-locating or telehousing your servers with another company. This is a popular alternative to dedicated servers where you provide your own equipment and ship it to the data center. The benefits is that you pay one time for the equipment rather then paying the monthly lease charges associated with a dedicated server. Keep in mind that you will still need to pay for the space your server takes up in the data center and the bandwidth it uses.

Data Center – Some times referred to as the DC, this is the physical location (ie: building) where the servers are kept. The DC's usually have a fiber optic backbone connection (ie: OC48), redundant power delivery, temperature control and extreme security.

Dedicated Hosting – This is a type of hosting where you own/rent an entire server. This means you have full (root) control of the server and don’t need to share it with anyone else. This becomes crucial for running big sites that require a lot of server resources.

DDoS – Distributed Denial of Service Attack. This is an attack where an attacker uses multiple machines to attack and over load your server. In a simpler single-machine attack it is refered to as a DOS (Denial of Service Attack).

ISP – An Internet Service Provider (ISP) is a company that provides internet access and other similar services to consumers. In the early days of the internet this category was very broad and included service providers like web hosts. These day's the term ISP usually refers to the telecoms bandwidth providers (like AT&T). This also includes companies that provide dial-up, ISDN, phone and cable internet services.