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Your patience pays off, subletting allows you to create multiple logical networks that exist within

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a single class A, B or C network.

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If you do not subnet, you are only able to use one network from your class A, B or C network, which

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is, well, pretty unrealistic.

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So subnetwork is the process of designating some high order bits from the host part as part of the network

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prefix and adjusting the subnet mask appropriately.

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So this divides a network into smaller subnets, in other words, in order to subnet a network, extend

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the natural mask with some of the high order bits from the host ID portion of the address in order to

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create a sub network ID.

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So I'll give you an example.

11
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Let's take a classy network of one nine two one six eight dot zero, which has a natural mask of two

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five 5.2, five 5.2 five 5.0.

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You can create subnets by moving to bits from the host part to the network prefix.

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Now, the last octet of the network mask starts with 11.

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So this eight bit corresponds to one nine two in decimal form.

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Now, the network ID is 26 bit in Ceyda notation, it's now a slash 26 subnetwork.

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You can find the network prefix by a bit wise and operation between the IP address and the subnet mask.

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The number of sub networks available and the number of possible hosts in a network may be readily calculated.

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In our example, two bits were borrowed to create subnetwork.

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Thus creating two to the power of two possible subnet.

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You with me?

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So now let's calculate the maximum number of hosts for each subnet.

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In our example, 26 bits are used to define the network.

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The remaining bits after the subnet bits are used for dressing hosts within a subnet.

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So the host part of the IP address is six bit all zeros and the old ones values for the host ID are

26
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not allowed in a subnetwork, right.

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These two values are reserved for the network address and broadcast address, respectively.

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So the maximum number of hosts which can be addressed in these sub networks is two to the power of six

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minus two, which equals 60 to.

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Excellent.

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So as a result, the IP addresses of the devices in the subnetwork, one nine two one six eight two

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one two eight 26 will be between one nine two one six eight, not two, not one to nine and one nine

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two one six eight two one nine zero.