Cisco CCENT/CCNA ICND1 100-101 Official Cert Guide

Appendix H. Practice for Chapter 20: Variable-Length Subnet Masks

Practice Problems

This appendix includes two varieties of VLSM practice problems related to Chapter 20, “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 whether 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 CCENT and CCNA blog, which is linked from the author’s website, www.certskills.com.

Practice Finding VLSM Overlaps

Table H-1 lists three ...