Subnetting (Aw shit)

Question 1

What are the IP class ranges

Answer 1

A - 0-126
B - 127-191
C - 192-224 (?)

Question 2

What are the five rules of answering subnetting questions

Answer 2

1) Rule of classes - determine the class of your subnet first as this will tell you its default subnet.

2) Rule of squared - Use 2^x to determine available hosts and subnets, where X = the number of host or network bits accordingly. Keep in mind for finding subnets you need to count from the class subnet, not the very start of the IP. For example: 80.160.0.0/20 is a class A subnet, and therefore we have 12 network bits from the end of the class A default subnet to the end of our /20 subnet. 2^12 = 4096 subnets.

3) Rule of diminishing host IPS - when you add another bit to the network ID, it stops the hosts using it. This means a /25 address will stop hosts using the 128 bit at the start of the octet for their own device IPs, reducing the highest IP available to 127

4) Rule of -1 – Always take away one host ID to account for gateway

5) Rule of direction - Work from left to right when adding network IDs, not left to right.

Question 3

Free card: Use this site to quiz yourself

Answer 3

https://ipcisco.com/subnetting-quiz-1-n485hju/

Question 4

What are the whack counts per octet

Answer 4

8, 16, 24, 32

Question 5

For broadcast addresses on IPV4 networks, will the broadcast address always end in 255?

Answer 5

No. Broadcast addresses are usually the LAST possible IP address in a subnet, which isn’t always 255.

For example, a network ID of 172.18.16.0/21 has a broadcast of 172.18.23.255.

In other words, if you had all the host bits of the host IDs together on each octet (separately) you get the broadcast IP.