Access-lists are the cornerstone of security in networking. They are used on Routers, Switches and Firewalls and are often a challenge to understand when first starting your career in networking. Before we dive into the configuration of access-lists, or otherwise known as ACL’s (Access Control Lists), it’s important to get an understanding of the concepts, […]
CIDR was invented in 1990, and was the change that allowed routers to use classless addresses to route traffic instead of class-full addresses. This helped a huge amount as before its invention, routers could only route traffic based on full classes. If we look at Class A address for example, there are only 126 of […]
Hashing is very different from encryption even though so many people believe it is an encryption protocol. Yes it does scramble the data, so from that aspect it is an encryption program, but the big difference between hashing and encryption, is that Hashing is mathematically impossible to reverse. Now I’m not the kind of person […]
Ports are logical channels that devices use to identify a type of traffic. If you can imagine that you and I have a 10 meter cable, that has 10,000 wires running through it, and I take 2 of the wires and attach them into the ends of a battery, and you choose 2 wires on […]
I’m sure you can imagine that trying to administer an IP address for every single person on the internet would be near impossible. Added to the fact that companies don’t want every computer in their network to be accessible on the internet for security reasons. The Internic and IANA (the two governing bodies for IP […]
The way that IP addresses have been used and allocated over the years has changed somewhat, however the principles have not changed. In order to better manage IP addresses they were put into classes and each class followed certain rules. In this post we are going to focus on the Class-full address structures, and understand […]
As the name indicates, and IP address is an address that computer equipment uses to be able to communicate with each other. It is made up of 4 octets (separated by a ‘.’), each of which is 8 bits in size (32 bits in total). If we look at our binary table for 8 bits, […]
Hex or Hexadecimal, is a 16-base number system with values from 0-9 as well as ABCDEF where A=10, B=11, C=12, D=13, E=14, F=15. Hex is used in many things in IT, most commonly seen in Mac addresses (A unique identity number on every Network Card). It is also seen in certain features such as HSRP […]
The concept of encryption can be quite daunting when you first look at it, however the basic concept of encryption is not that hard to understand When I moved into my house, my bathroom door didn’t have a key. The previous owners of the house didn’t know what key was needed for that door […]
The first and most important thing to understand when it comes to networking is binary. Without the fundamental understanding of binary and how it works, it would be very difficult to understand IP addresses, and without an understanding of IP addresses, it’s impossible to understand networking. So what is binary? Binary is a number system […]
Bit’s, crumbs, nibbles, bytes, megabytes ??? Ever wondered why when you buy a 250 Gigabyte hard drive and you format it, you never actually get 250 Gigabytes??? Well it’s all in the exact wording used, and how the information is reported to you. If we understand the terms of binary, and the difference between a […]