Appendix D. Practice for Chapter 5: Variable Length Subnet Masks

Practice Problems

This appendix includes two varieties of VLSM practice problems related to Chapter 5, “Variable Length Subnet Masks.” The first type of problem lists pairs of IP addresses and masks from a network, and your job is to discover if any of the subnets implied by those addresses/masks overlap. The second problem starts with a list of existing subnets, and your job is to find the numerically lowest new subnet ID that could be added to that internetwork for a given mask.

Note that you can find additional practice at the author’s CCNA blog, which is linked from the author’s website,

Practice Finding VLSM Overlaps

Table D-1 lists four practice problems ...

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