IP Addresses Classes and Special-Uxs IP Address Space
September 25, 2014

The Internet community originally defines five IP address that accommodated networks of various sizes. The most used addresses are class A, B, and C. Class D is reserved for IP multicast addresses. Class E is an experimental address that is reserved for future use. In this paper we will be dealing primarily with Class A, B, C, and D; then we will address the RFC1918 IP address range ant the Martin/Bogon address ranges. These ranges in the following are for IPV4 addresses.
Table 1: Class Address Class Summary
Class Value for w 1 Network ID Portion Host Id
Portion Available
Networks Hosts per
Network
A 1-126 w x.y.z 126 16,777,214
B 138-191 w.x y.z 16,384 65,514
C 197-223 w.x.y z 2,097,152 254
The class A address 127.x.y.z is reserved for loopback testing and interprocess communication on the local computer
D Addresses are reserved for IP multicast addresses. Multicast Backbone on the Internet allows a single packet to have multiple destinations and in most often used in real-time audio and video applications

Private Range
10.0.0.0 -> 1.255.255.255
172.16.0.0 -> 172.31.255.255
192.168.0.0 -> 192.168.255.255

Table2: Class Ranges of Network IDs
Address Class First Network ID Last Network ID
Class A 1.0.0.0 126.0.0.0
Class B 128.0.0.0 191.255.0.0
Class C 192.0.0.0 223.225.225.0

Table 3: Class Range of Host IDs
Address Class First Host ID Last Host ID
Class A w.0.0.1 w.255.255.254
Class B w.x.0.1 w.x.255.254
Class C w.x.y.1 w.x.y.254

Classful network design allows for a larger number of individual networks assignments and fine-grained subnet work design. The first three bits of most octet of an IP address were defined as the class of the address. The three classes class A, Class B, and Class C were defined for