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I know, I know what you're thinking, you're really chomping at the bit to get to subletting, but

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before we talk about it, it's better to learn the IB classes and the subnet masks first.

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Right?

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Octets of the IP address are broken down to provide an addressing scheme that can accommodate large

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and small networks.

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So they're basically five different classes of networks and they range from A to E.

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We're going to focus on classis A, B and C, which provide unicast addresses for networks of three

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different network sizes, Class D is for multicast networking and the classi address ranges reserved

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for future or experimental purposes.

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So given an IP address, its class can be determined from the three high order bits and by that I mean

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the three leftmost bit in the first octet.

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In a class I address, the first octet is a network portion, so Class AA has a major network address

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of one that zero zero zero all the way through one to seven 255, 255 255.

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The next 24 bits are for the network manager to divide into subnets and hosts as he or she sees fit.

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Class addresses are used for networks that are more than sixty five thousand five hundred and thirty

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six hosts.

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In a Class B address, the first two octets are the network portion, so Class B has a major network

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address of one two eight zero zero zero all the way through one nine one two five 5.2 555 Datu five

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five.

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Octets, three and four, that means 16 bit are for local subnets and hosts.

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Class IP addresses are used for networks that have between 256 and sixty five thousand five hundred

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thirty four hosts.

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And finally, in a classy address, the first three octets are the network portion.

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Class C has a major network address of one nine two zero zero zero all the way through two to three

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to five 5.5 5.2 five five octet for eight bits is for local subnets and hosts perfect for networks with

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less than two hundred and fifty four hosts.