Subnetting BEST Method Example 2

10.128.192.0/18

Requirement = 30 Subnets (Max Hosts)

Total Number of Subnets = 2^n (network bits) (count bits from Left to Right)

= 2^5

= 32 Total Subnets

New Mask = /18+/5 = /23

New IP Address = 10.128.192.0/23

Host bits

/32 - /23 = 9 Hosts bits

How many Hosts/Subnet = 2^n -2 (host bits) (count bits from Right to Left)

= 2^9 - 2

= 512-2

= 510 Hosts/Subnet

10.128.192.0/23 (First NID)

10.128.192.255/23 (255 Hosts) + 10.128.193.255/23 (255 Hosts)

10.128.194.0/23 (Second NID)

10.128.196.0/23 (Third NID)

10.128.196.0/23 (Fourth NID)

. .

10.128.254.0 (Last NID)

10.128.254.255 (Last BID)

10.128.255.255

Reference:

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