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New Member

Subnet Mask Config

Plss help me, how can I solve this question................

Find the total no of hosts subnetted with mask subnetted with mask subnetted with mask subnetted with mask

Everyone's tags (2)

Re: Subnet Mask Config

All the subnets have a /30 mask, that means each subnet will have 1 network ID, 2 IP addresses for hosts and 1 broadcast address. So 50% from the particular ranges can be used for hosts, the other 50% are network IDs and broadcast addresses.

I'd calcultate the number of addresses for each of the given ranges and simply divide by two.

/18: 2^ (32 - 18) = 2^14 = 16.384 => 50% => 8.192 possible hosts in that range


Hope that helps



Note that the first subnet ID is also the ID of the given range:

And the broadcast address of the last subnet is also the broadcast address of the given range:

New Member

Subnet Mask Config

Thank you very much Sir.

One more issue which option will allow to configure 113 P2P links ??

Subnet Mask Config

You're welcome.

I guess the "classic"  approach would be to use /30-subnets which would requiere 4 x 113 IP addresses.

However, for P2P links in particular, you can also use /31-subnets if supported:

In this case you would need only 2 x 113 IP addresses; so subnetting a /24-prefix would be sufficient.

Best regards


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