Definitions

Security

Definitions

For those not familiar with computer security, let's look at simple definitions of a few words.

Protocol

A protocol is a computer communication language. Computers communicate with each other over the internet using various protocols.

Port

A port identifies a type of service. For example, port 53 is used for the domain name server. So if something is sent to port 53, the computer receiving it knows it is for the domain name server.

IP Address

An Internet Protocol address, normally called an IP address, is the address of a specific computer or network. An IP address is made up of four numbers separated by dots, and each number can be anything from 0 to 255. An example is "220.65.8.129." Every computer in the world, that is connected to the internet, is designated an IP address. When you connect to the internet, your internet service provider designates an IP address to your computer. Your internet service provider has a range of IP addresses, and you may have any one from that range each time you connect to the internet. Computers belonging to large organizations, or hosting websites, always have the same IP address.

Website

A website is shown like "www.anywebsite.com." Many websites can be hosted at one IP address.

Domain Name Server

A domain name server has a record of where all the web sites are in the world. Have you ever wondered, when you send something to www.anywebsite.com, how your computer knows where to send it? It could be anywhere in the world. Your computer sends a packet to the domain name server asking it. The domain name server sends a packet back telling your computer where it is.

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