Name: __________________________
Class C Subnetting Worksheet
Class C Subnetting Examples
1) Complete the table:
Network Address: 193.18.55.0 (Class C) – Default Subnet Mask 255.255.255.0
Subnetworks Needed: 25
Number of borrowed host bits required: 5 (25 = 32 – 2 = 30 nets max = 5 bits required)
Magic Number: 8 (value of lowest bit borrowed = 11111xxx – determines subnet offset)
Custom Subnet Mask: 255.255.255.248 /29 (sum of borrowed bits)
Subnetwork Table
Subnet Address Number First Host Last Host Broadcast
193.15.55.0 N/A NOT USEABLE NOT USEABLE NOT USEABLE
193.15.55.8 1 193.15.55.9 193.15.55.14 193.15.55.15
193.15.55.16 2 193.15.55.17 193.15.55.22 193.15.55.23
193.15.55.24 3 193.15.55.25 193.15.55.30 193.15.55.31
193.15.55.32 4
193.15.55.40 5
193.15.55.48 6
193.15.55.56 7
193.15.55.64 8
193.15.55.72 9
193.15.55.80 10
193.15.55.88 11
193.15.55.96 12
193.15.55.104 13
193.15.55.112 14
193.15.55.120 15
193.15.55.128 16
193.15.55.136 17
193.15.55.144 18
193.15.55.152 19
193.15.55.160 20
193.15.55.168 21
193.15.55.176 22
193.15.55.184 23
193.15.55.192 24
193.15.55.200 25
193.15.55.208 26
193.15.55.216 27
193.15.55.224 28
193.15.55.232 29
193.15.55.240 30
193.15.55.248 N/A NOT USEABLE NOT USEABLE NOT USEABLE
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