Subnetting and Subnet Masks Explained

What is Subnetting ?-Subnetting is the process of diving a network into small networks and is a common task on IPV4 networks. Before we discuss how to implement it it is useful to understand why and when we need to do it and to do that we are first going to work through a simple analogy to illustrate the problem subnetting solves

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Host Name Resolution Methods Explained

On computer and home networks when you type an Internet address into a web browser the web browser needs to convert that web address into an IP address. To do that it uses the the name resolution processes provided by the host machine. There are several ways that the host machine can resolve a domain name. The main ones are:

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DNS Lookups Explained

In this tutorial we will examine what happens when you use DNS to lookup or resolve a domain name to an IP address. We look at how DNS lookups work, and the exact process involved when looking up a domain name. We follow the client DNS query as it is processed by the various DNS servers in the response chain. Before we start it might be useful to compare DNS name resolution with a standard question and answer that takes place in everyday life.

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TCP vs UDP -What’s The Difference?

If you are just starting with TCP/IP then you are probably wondering why there are two transport layer protocols- ( TCP and UDP ). Why don’t we just have one? After all TCP seems to be the best option anyway. The aim of this short introductory tutorial is to explain the basic differences between the two and why each protocol is needed, and when they are used.

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Understanding The Domain Name Structure

To understand the domain name structure you really need to understand the problem the structure was meant to solve. The Domain Name Structure and Domain Name System were developed to organise and find the IP addresses of Computers on large distributed networks.

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Understanding DNS – Beginners Guide to DNS

DNS (Domain Name System) is one of the most important technologies/services on the internet, as without it the Internet would be very difficult to use. DNS provides a name to number (IP address) mapping or translation, allowing internet users to use, easy to remember names, and not numbers to access resources on a network and the Internet.

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TCP/IP Ports and Sockets Explained

On a TCP/IP network every device must have an IP address. The IP address identifies the device e.g. computer. However an IP address alone is not sufficient for running network applications, as a computer can run multiple applications and/or services. Just as the IP address identifies the computer, The network port identifies the application or service running on the computer. The use of ports allow computers/devices to run multiple services/applications. The diagram below shows a computer to computer connection and identifies the IP addresses and ports.

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