533

Complete the attachments(s).  Worth 50 points.

The Practice Exercise has the last question referring to IP address 199.1.1.5.  The question references the last row of the table itself in which you found the subnet and broadcast for 199.1.1.4.  You would use the same subnet mask for the 199.1.1.5. In essence, you answered the Network ID and Broadcast ID when you calculated the answer for 199.1.1.4.  Now tell me the assignable host addresses.

The Comprehensive Exercise is a conglomeration of several learning concepts: 1) establishing the range of a subnet, 2) the number of bits to take for a specific number of subnets, knowing how many subnets neeeded if give parameters, and use CIDR.

By the way, you should read the Network Addressing document and/or the textbook chapter 5 before you attempt these exercises (See reading assignment for this week).  These two exercises are considered special activities and are worth 50 points (40 for Comprehensive and 10 for Practice). Similar exercises will occur on the 

MidTerm

 and Final Exams

Example 

Determining the Number of IP Subnets and Hosts

CREATED BY A VALID MASK. NO CIDR OR VLSM.

Step One

Use the first octet of the IP address to determine the class of address (A, B, or C).

169.199.109.137

   = CLASS B

255.255.255.192

Step Two

Use the class of the address to determine which octets are available for hosts.

CLASS B = Network. Network. Host. Host

                                    169.199.109.137

                                    255.255.255.192

Step Three

Look at the host octet(s) in the subnet mask. Use the 

“Possible Masks” chart

 to determine which bits are set to one. If no bits are set to one, there are no subnets. If any bits are set to one, proceed to step four.

169.199.109.137

255.255.255.192 = 11111111 11000000 (host octets only)

Step Four

Count the total number of ones in the host octet(s) of the subnet mask. Call this number X. Raise 2 to the power of X. Use the 

“Powers of 2” chart

 if necessary. This is the number of potential subnets created by the mask. Two of these potential subnets are normally not usable.

11111111 11000000 = 10 ones.  210 = 1,024 – 2 = 1,022 usable subnets created.

Step Five

Count the total number of zeros in the host octet(s) of the subnet mask. Call this number Y. Raise 2 to the power of Y. Use the “Powers of 2” chart if necessary. This is the number of potential subnets created by the mask. Two of these numbers are never used to address hosts.

11111111 11000000 = 6 zeros.  26 = 64 – 2 = 62 usable host addresses created.

Sample 

you need to complete the chart here is additional info to help you 

1. Complete the table below:

Network Address (ID)

Default

Subnet Mask

# of  Required Subnets

Max Number of (usable) Subnets

Number of Network bits added

Subnet Mask

172.16.0.0

255.255.0.0

5
6
3

255.255.224.0

172.17.0.0

255.255.0.0
50

 62

 6

 255.255.252.0

192.168.23.0

255.255.255.0

10

 14

 4

10.0.0.0

255.0.0.0

4000

12

255.255.240.0