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Subnet Mask Config

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

Find the total no of hosts

10.10.0.0/18 subnetted with mask 255.255.255.252

10.10.0.0/25 subnetted with mask 255.255.255.252

10.10.0.0/16 subnetted with mask 255.255.255.252

10.10.0.0/24 subnetted with mask 255.255.255.252

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3 REPLIES

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

Rolf

P.S.:

Note that the first subnet ID is also the ID of the given range:  10.10.0.0

And the broadcast address of the last subnet is also the broadcast address of the given range: 10.10.63.255

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:

http://packetlife.net/blog/2008/jun/18/using-31-bit-subnets-on-point-point-links/

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

Best regards

Rolf

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