Why my computer subnet works like this? [closed]

Question

When I type "ipconfig" within my command line, I get this thing:

   IPv4 Address. . . . . . . . . . . : 10.100.102.6
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 10.100.102.1

Why tha hack my subnet mask is 255.255.255.0 and my IP CLASS is A? Because this thing, I have 2^16 of network prefix and 2^8 hosts can be - which is wnormous number I will never use! How can I make my IP to be class C (to be able to host only 2^8 hosts, and then subnneting this IP to be \29 so I my network will be able to hold just 5 computers trying to connect.?)?

Answer 1

You are using a mask 255.255.255.0, it means that the range of addresses is from 10.100.102.0to 10.100.102.255.

In 1993, the Internet Engineering Task Force published RFC 1518 and RFC 1519. These RFCs define a new concept called Classless Inter Domain Routing. The most important thing of those RFCs is that obsoletes the Classful Network where ranges where associated with classes with fixed netmasks.

Answer 2

Your ip is in the 10 range because it belongs to the group of private IP, which are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. Since this ranges are not routed onto to the public network you can do whatever you want with this ips on your home or office network.