Question

Is a “subnet” a logical structure or a physical structure”? Why would a network administrator chose to use a CIDR addressing scheme rather than use the class A, class B, and class C designations usually associated with IPv4?

What are some of the major differences between IPv4 and IPv6? Since IPv6 is not backward compatible with IPv4, what are some of the ways in which a network administrators can assure that both IPv4 and IPv6 addresses will be accommodated within their networks?

Answer 1

Answer 1
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subnet is logical structure which devides whole network into sub-network to manage easily as class A uses /8 class B uses /16 and class C uses /24 but what if we want to use /11 /12 /23 /7 etc ? so this is called classless inter domain routing which does not lie in any of the class A,B or C.

Answer 2
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ipv4 has 32bit of length and at the max ip addresses limit is 4,294,967,296 but as day by day devices are increases we will ran out of this range in future so to overcome this issue IPv6 is in the present system to be implemented with 128 bit of length as we can not degrade from IPv6 to IPv4 because 128 bit can not fit into 32 bit that's obvious but vice versa is possible.

Network admin can configure a router which support both the version to support network system.

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