This chapter covers the following topics:
Understanding IP Addresses—Describes the structure of IP addresses and reviews binary, classful addressing, and the steps to calculate subnets.
Understanding Summarization—Proposes a way to take a list of addresses and convert them into a single summary or to provide a "best fit" set of summaries.
This chapter discusses IP addressing and summarization. It begins with a short review of CCNA concepts, including binary and IP subnetting. It then uses those concepts as a springboard to discuss summarization and address planning.
The first section, "Understanding IP Addresses," describes the structure of an IPv4 address and provides classful and classless methods that can be used to calculate the range of a given subnet.
The second section, "Understanding Summarization," builds on the range of calculation methods by describing how larger groups of addresses can be advertised in the simplest possible manner. This section reviews why summarization is important and discusses how to apply summarization to network design.
The topics in this chapter are indirectly important for the BSCI exam. Although you will not be tested directly on these topics, each routing protocol will introduce a technique to create summaries and you will be tested with questions that combine your understanding of summarization and the commands necessary to apply summarization.
The purpose of the "Do I Know This Already?" quiz is to help you decide which parts of this chapter to use. If you already intend to read the entire chapter, you do not necessarily need to answer these questions.
The 11-question quiz, derived from the major sections in the "Foundation Topics" portion of the chapter, helps you determine how to spend your limited study time.
Table 2-1 outlines the major topics discussed in this chapter and the corresponding quiz questions.
|Foundation Topics Section||Questions Covered in This Section||Score|
|Understanding IP Addresses||1–9|
The goal of self-assessment is to gauge your mastery of the topics in this chapter. If you do not know the answer to a question or are only partially sure of the answer, you should mark the question wrong for purposes of the self-assessment. Giving yourself credit for an answer you correctly guessed skews your results and might provide you with a false sense of security.
|1.||What is the binary for 172?
|2.||What is the binary for 128?
|3.||What is the decimal for 1100 0000?
|4.||What class is 172.16.1.1?
|5.||What class is 10.37.5.11?
|6.||What is the CIDR-notation equivalent of 255.255.255.0?
|7.||What is the dotted-decimal equivalent of /27?
|8.||What is the network for the address 192.168.37.62/26?
|9.||What is the broadcast address for the host address 192.168.190.55/27?
|10.||Given the addresses 10.1.8.0/24 and 10.1.9.0/24, which of the following is the best summary?
|11.||Given the addresses 10.1.138.0/27, 10.1.138.64/26, and 10.1.138.32/27, which of the following is the best summary?
You can find the answers to the "Do I Know This Already?" quiz in Appendix A, "Answers to Chapter 'Do I Know This Already?'Quizzes and Q&A Sections." The suggested choices for your next step are as follows: