An IP subnetting design effort is under way at a company. So far, the senior engineer has decided to use Class B network 172.23.0.0. The design calls for 100 subnets, with the largest subnet needing 500 hosts. Management requires that the design accommodate 50 percent growth in the number of subnets and the size of the largest subnet. The requirements also state that a single mask must be used throughout the Class B network. How many masks meet the requirements

The answer is "0".

Explanation:

The mask should describe sufficient subnet bits for build 150 subnet masks with 50% development. The Mask thus needs a minimum of 8 subnet bits (7 subnet bits supply 27, or 128, subnets, and 8 subnet bits supply 28, or 256, subnets). Similarly, such a need to grow by 50% of its size of the main subnet needs, that host part to amount to 750 hosts/subnet. There's not enough 9 host bits (29 - 2 = 510), yet 10 network bits have 1022 host(s)/subnet (210 – 2 = 1022). This same maximum mask project requires to be 34 bits, (at least) in the form of 16 network bits, because of the Class B network, but there are only 32 bits, therefore no single mask meets its requirements.

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