Subnetting Example Solution
Consider the following network on a vessel that is comprised of these 6 networks:
1. Operation technology – 24 devices
2. VoIP – 16 devices
3. Business Network – 9 devices
4. Server LAN – 4 devices
5. Crew LAN – 15 devices
6. Crew WiFi – 40 devices
Allocate networks to the above networks by subnetting the class C network: 10.10.10.0/24.
Network Description
Prefix
Network Address
Broadcast Address
Host Address Range
Unused Addresses
Crew WiFi
/26
10.10.10.0
10.10.10.63
.1-.62
22
Operation technology
/27
10.10.10.64
10.10.10.95
.65-.94
6
VoIP
/27
10.10.10.96
10.10.10.127
.97-.126
14
Crew LAN
/27
10.10.10.128
10.10.10.159
.129-.158
15
Business Network
/28
10.10.10.160
10.10.10.175
.161-.174
5
Server LAN
/28*
10.10.10.176
10.10.10.191
.177-.190
10
*Could also me divided into two /29s (leaving the server network with 2 spare IP addresses, although I opted for the /28 for simplicity. If that occurred
there is also a spare /29.
How much space is left unallocated? An entire /26 – 62 host addresses unallocated (from .192-.255). All networks have space or further growth.
