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248 Chapter 5: Network Protocols
Step 3
Record the results of the Boolean AND below the two numbers.
Step 4
Convert the result of Step 3 back into decimal, 8 bits at a time.
Repeating the same samples from Table 5-15, using the Boolean AND delivers the following
results:
An example network will be used as a backdrop to discuss this binary view of subnetting.
Figure 5-22 illustrates six different subnets. Table 5-16 provides the list of subnet numbers.
Address (Step 1)
8.1.4.5
0000 1000 0000 0001 0000 0100 0000 0101
Mask (Step 2)
255.255.0.0
1111 1111 1111 1111 0000 0000 0000 0000
Result (Steps 3 and 4)
8.1.0.0
0000 1000 0000 0001 0000 0000 0000 0000
Address (Step 1)
130.4.100.1
1000 0010 0000 0100 0110 0100 0000 0001
Mask (Step 2)
255.255.255.0
1111 1111 1111 1111 1111 1111 0000 0000
Result (Steps 3 and 4)
130.4.100.0
1000 0010 0000 0100 0110 0100 0000 0000
Address (Step 1)
199.1.1.4
1100 0111 0000 0001 0000 0001 0000 0100
Mask (Step 2)
255.255.255.0
1111 1111 1111 1111 1111 1111 0000 0000
Result (Steps 3 and 4)
199.1.1.0
1100 0111 0000 0001 0000 0001 0000 0000
Address (Step 1)
172.100.2.2
1010 1100 0110 0100 0000 0010 0000 0010
Mask (Step 2)
255.255.255.0
1111 1111 1111 1111 1111 1111 0000 0000
Result (Steps 3 and 4)
172.100.2.0
1010 1100 0110 0100 0000 0010 0000 0000
Address (Step 1)
17.9.44.3
0001 0001 0000 1001 0010 1100 0000 0011
Mask (Step 2)
255.255.255.0
1111 1111 1111 1111 1111 1111 0000 0000
Result (Steps 3 and 4)
17.9.44.0
0001 0001 0000 1001 0010 1100 0000 0000
ch05.fm Page 248 Monday, March 20, 2000 5:06 PM