IPv4 VLSM Allocation
Allocate conventional host subnets largest-first inside one parent.
Your numbers
Request 1
Uses conventional network and broadcast reservations; /31 and /32 allocations are not used.
Scenario comparison
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Formula
For each requirement choose 2^ceil(log₂(hosts+2)); allocate largest blocks first
Allocate conventional host subnets largest-first inside one parent.
Worked example
- Parent network address
- 192.168.0.0
- Parent prefix
- 24
- Required host counts
- 100, 50
- Request 1
- 192.168.0.0/25
- Request 2
- 192.168.0.128/26
- Unallocated addresses
- 64
Scope and limitations
Uses conventional network and broadcast reservations; /31 and /32 allocations are not used.
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Formula version: b350dde622ac · Example checked: