Understanding IP addressing and subnetting

Nowadays, a lot of effort is being made to advance the development of IP addressing technologies. Specifically, IPv6 addressing is the best example of such an effort. Nevertheless, even though the IPv6 addressing technology is becoming more and more plausible, it still prefers the role of spectator in the great arena of the internet, where IPv4 addressing technology continues to be the norm.

• IPv4 addressing technology is the fourth version of IP addressing. In brief, an IPv4 address, or simply IP address, is a logical element that consists of 32 bits. It is organized into four (4) groups of eight (8) bits (octet) each pided by a decimal point. For the purpose of easier interpretation, it is represented in decimal format (for example, 192.168.1.1). Knowing that one (1) byte equals eight (8) bits, then an IP address is four (4) bytes. From that, the total number of IPv4 addresses is 2³² , or 4,294,967,296. When compared with the total world population, it is obvious that nearly 3 billion IP addresses are missing if we assign an IPv4 address to every inpidual.
• IPv6 addressing technology has been introduced to overcome IPv4 limitations. Similar to IPv4, IPv6 is a logical component of computer networks too. However, it consist of 128 bits organized into eight (8) groups of sixteen (16) bits (hextet) each pided by a colon. For the purpose of easier interpretation, it is represented in hexadecimal format (for example, 2001:0DB8:85A3:0000:0000:8A2E:0370:7334). From that, the total number of IPv6 addresses is 2¹²⁸ , or 340,282,366,920,938,463,463,374,607,431,768,211,456. And that is more than enough IPv6 addresses!
• IPv4 subnetting helps implement multiple logical networks within existing IPv4 classes such as A, B, and C. In subnetting, a subnet mask plays an important role in determining the size of the network. So, by definition, a subnet mask is a 32-bit address used in combination with an IPv4 address to indicate the network and its computers. Each class has a default subnet mask. Table 1.1. shows the default subnet masks for each class of IPv4 addresses.

Table 1.1. Default subnet masks for each class of IPv4 addresses: