Daily Tutorials

INTRODUCTION TO COMPUTER NETWORKING/ INTERNETWORKING

Good morning students, today we shall be looking at a very interesting topic, still on the internet. It is called networking or your can call it internetworking. Come on, come on!! Don’t get scared nobody is telling you to market or sell anything. I want to talk about the fundamentals, what makes the internet work. Now a simple definition;

Networking is a process of connecting more than two or more computers physically present (i.e. on the same subnet) to each other so that they can exchange information, such as e-mail messages or documents, or share resources such as disk storage or printers. In most cases, this connection is made via electrical cables that carry the information in the form of electrical signals. But in some cases, other types of connections are used.

On the other hand internetworking is a process of connecting two or more networks together using routers and switches. It can also be describes as a connection between computers through the internet. An internetwork can be created by connecting two or more LANs or WANS via a router and configure a logical network addressing scheme with a protocol such as Internet Protocol (IP).

Now what is an IP address?

IP Address

       An internet protocol address (IP address) is a numerical label assigned to each device (e.g. computer, printer) participating in a computer network that uses the internet protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing.

       IP addresses are of two versions; Internet Protocol version (IPV4) and Internet Protocol Version 6 (IPV6). IPV4 is made up f 32 bits whereas IPV6 is made up of 128 bits for the address. IPV6 was created in 1995 due to the enormous growth of the internet and the prediction that we will someday run out of IPV4 addresses. In future the Internet Engineering Task Force (IETF) intends that IPv6 replaces IPV4 addressing.

       Although IP addresses are binary numbers, they are usually displayed in decimal notations and hexadecimal notations for IPV4 and IPV6 respectively.

Decomposition of an IPV4 address from dot-decimal notation to its binary value. (culled from Wikipedia)

Decomposition of an IPV6 address from hexadecimal representation to its binary value (culled from Wikipedia)

IP addresses can also be grouped into public IPs and private IPs. Public IPs are those addresses that have been assigned by the Internet Assigned Numbers Authority (IANA) as addresses reserved to be routable on the internet. While private IPs are those IP addresses that are reserved for use on only internal networks, they are not routable on the internet. There are also specially reserved addressed like 127.x.x.x for diagnostic functions, 255.255.255.255 for broadcasts to all hosts on the local network and 169.254.0.1 to 169.254.254 range for Automatic Private IP Addressing (APIPA); which automatically assigned when a computer is unsuccessful in getting an address from a DHCP Server.