Designing subnets ( computer networking)?

A company granted site address block of class C which is 207.70.64.0. The company needs [at least] six subnets.

A) Design the six subnets

B) Calculate the number of hosts possible for each subnet

C) Calculate the broadcast address and the subnet IP addresses of each [subnet]

D) Request the sub network using block in terms of classes

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What we know:

a. We are to use the block of IPs that starts with 207.70.64.0

b. It's a Class C IP so we know the default Subnet Mask is 255.255.255.0 or /24.

c. We know a /24 gives us 256 IPs. We know this because a /24 in binary looks like:

1111 1111.1111 1111.1111 1111.0000 0000. And when we take the number of zeroes in the mask and use the formula: 2^(# of zeroes) = # of hosts/IPs, we get 2^8 = 256.

d. We [should] know that network objects are provisioned in Powers of 2. (2, 4, 8, 16, 32, etc.) Because 6 (subnets) is NOT a Power of 2, this means we cannot make only 6 subnets -- we have to make 8. So, we'll have to divide 256 by 8. This gives us 32 IPs per subnet.

e. Now we can map out the 6 needed subnets: (Starting IP --> Broadcast IP)

1. 207.70.64.0 -------> .31

2. 207.70.64.32 -----> .63

3. 207.70.64.64 -----> .95

4. 207.70.64.96 -----> .127

5. 207.70.64.128 ---> .159

6. 207.70.64.160 ---> .191

<--- the extra 2 subnets --->

7. 207.70.64.192 ---> .223

8. 207.70.64.224 ---> .255

f. Now we need to determine the new Subnet Mask to use with each new subnet. There are many ways to do this. One way is to imagine a subnet mask with all 1s in it:

- 1111 1111.1111 1111.1111 1111.1111 1111

Now, knowing that zeroes represent the number of hosts the mask will allow, and knowing that we must use the Power of 2 to allocate hosts, how many zeroes do we need to support 32 hosts?

Again, simply use the formula: 2^(# of zeroes) = # of hosts, and we get: 2^h = 32, which means h = 5. We'll need to put 5 zeroes at the end of the mask, like so:

- 1111 1111.1111 1111.1111 1111.1110 0000 = /27 = 255.255.255.224

And, unfortunately, I don't understand what Question D is asking.