bitmindframes

Scenario: Your company has been given the network address 172.16.32.0/19.

10101100 . 00010000 . 001 00000 . 00000000

After careful planning, looking at current needs and expansion, you realize you need a maximum of three subnets of 1,000 hosts, three subnets of 250 hosts, and several subnets for serial point-to-point links.

There are several ways to do this, but you have decided that you will variably subnet your network as follows: (We did it this way just for the exercise and to keep it somewhat simple.)

Step 1 : The maximum number of hosts any of your subnets will need is 1,000, so you decide to make the initial subnets 172.16.32.0/22. Write out the eight /22 subnets in binary and decimal form:

1. 10101100 . 00010000 . 001 000 00 . 00000000 172.16.32.0/22

2. 10101100 . 00010000 . 001 001 00 . 00000000 172.16.36.0/22

3. 10101100 . 00010000 . 001 010 00 . 00000000 172.16.40.0/22

4. 10101100 . 00010000 . 001 011 00 . 00000000 172.16.44.0/22

5. 10101100 . 00010000 . 001 100 00 . 00000000 172.16.48.0/22

6. 10101100 . 00010000 . 001 101 00 . 00000000 172.16.52.0/22

7. 10101100 . 00010000 . 001 110 00 . 00000000 172.16.56.0/22

8. 10101100 . 00010000 . 001 111 00 . 00000000 172.16.60.0/22

Step 2 : You only need three /22 subnets, so you reserved the first three for those subnets needing 1,000 hosts. Which ones are they?

1. 10101100 . 00010000 . 001 000 00 . 00000000 172.16.32.0/22

2. 10101100 . 00010000 . 001 001 00 . 00000000 172.16.36.0/22

3. 10101100 . 00010000 . 001 010 00 . 00000000 172.16.40.0/22

Step 3 : You decide to sub-subnet the fourth subnet (172.16.44.0/22) for the three subnets each needing 250 hosts. A /24 will work well for this. What are the three /24 sub-subnets you will use?

4. 10101100 . 00010000 . 001 011 00 . 00000000 172.16.44.0/22

4a. 10101100 . 00010000 . 001 011 00 . 00000000 172.16.44.0/24

4b. 10101100 . 00010000 . 001 011 01 . 00000000 172.16.45.0/24

4c. 10101100 . 00010000 . 001 011 10 . 00000000 172.16.46.0/24

4d. 10101100 . 00010000 . 001 011 11 . 00000000 172.16.47.0/24

Step 4 : The last (fourth) of the /24 sub-subnets (172.16.47.0/24), you decide to use for you serial point-to-point links. List the first five /30 sub-sub-subnets (if there is such a term):

4d. 10101100 . 00010000 . 001 011 11 . 00000000 172.16.47.0/24

4d1.10101100 . 00010000 . 001 011 11 . 000000 00 172.16.47.0/30

4d2.10101100 . 00010000 . 001 011 11 . 000001 00 172.16.47.4/30

4d3.10101100 . 00010000 . 001 011 11 . 000010 00 172.16.47.8/30

4d4.10101100 . 00010000 . 001 011 11 . 000011 00 172.16.47.12/30

4d5.10101100 . 00010000 . 001 011 11 . 000100 00 172.16.47.16/30

etc.

4d5.10101100 . 00010000 . 001 011 11 . 111111 00 172.16.47.252/30