Chapter 20. Introduction to IPv6 and IPv6 Addressing

This chapter covers the following topics:

  • Introduction to IPv6—Discusses the need for IPv6's larger address space and the features of IPv6.

  • The IPv6 Packet Header—Describes the fields in the IPv6 packet header.

  • IPv6 Addressing—Explains how IPv6 addresses are represented, and describes the details of each type of IPv6 addresses.

  • IPv6 Address Assignment—Describes how IPv6 addresses can be assigned to devices.

  • IPv6 Mobility—Discusses how IPv6 allows mobile users to stay connected.

This chapter begins the discussion of Internet Protocol version 6 (IPv6) and focuses on understanding the features of IPv6, its packet header, and its addressing types and structure. The chapter concludes with a discussion of IPv6 address-assignment strategies and IPv6 mobility.

A well-designed IPv6 network looks similar to a well-designed Internet Protocol version 4 (IPv4) network. Of course there are differences in addressing, but the hierarchical design discussed in Chapter 1, "Network Design," continues to be preferred because it supports summarization, which is the key to scalability.

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 12-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 20-1 outlines the major topics discussed in this chapter and the corresponding quiz questions.

Table 20-1. "Do I Know This Already?" Foundation Topics Section-to-Question Mapping
Foundation Topics SectionQuestions Covered in This SectionScore
Introduction to IPv61 
The IPv6 Packet Header2–4 
IPv6 Addressing5–10 
IPv6 Address Assignment11 
IPv6 Mobility12 
Total Score  


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.How long is an IPv6 address?
  1. 16 hexadecimal numbers

  2. 32 decimal numbers

  3. 128 bits

  4. 32 bits

2.For which field in the IPv4 header is there not a similar field in the IPv6 header?
  1. Version

  2. ToS

  3. TTL

  4. Checksum

3.How large is the basic IPv6 header (without any extensions)?
  1. 20 bytes

  2. 128 bits

  3. 320 bits

  4. 512 bits

4.Which of the following functions is implemented with extension headers?
  1. Fragmentation

  2. Flow labels

  3. TCP

  4. Checksum

5.Which of the following is a valid host unicast IPv6 address?
  1. 2001::240E::0AC0:3428:121C

  2. 2001:240E::0AC0:3428::

  3. 2001::0000::240E::0000::0000::0AC0::3428::121C

  4. 2001:0:240E::0AC0:3428:121C

6.What is the EUI-64 format interface identifier that corresponds to the MAC address 00-0C-27-A2-13-1B?
  1. C:27A2:131B

  2. 020C:27FF:FEA2:131B

  3. FEFE:C:27A2:131B

  4. 000C:27A2:131B:0000:0000

7.Which of the following is not supported by IPv6?
  1. Unicast

  2. Broadcast

  3. Multicast

  4. Anycast

8.An IPv6 enterprise will typically be assigned a prefix at which level?
  1. /3

  2. /8

  3. /16

  4. /48

9.A NIC has a MAC address of 00-0F-66-81-19-A3 and discovers a routing prefix of 2001:0:1:5::/64. Which IPv6 addresses are assigned to it?
  1. 2001::1:5:20F:66FF:FE81:19A3

  2. FE80::20F:66FF:FE81:19A3

  3. ::1

  4. FF02::1

10.IPv6 multicast addresses use which prefix?
  1. F000::/16

  2. FF00::/8

  3. 0::/8

  4. 4000::/8

11.Which two items does stateless autoconfiguration use?
  1. Multicast prefix

  2. Advertised prefix

  3. Advertised interface ID

  4. EUI-64 format interface ID

12.A mobile IPv6 binding is an association between which of the following?
  1. Home address

  2. Correspondent nodes

  3. Prefix

  4. Care-of address

The answers to the "Do I Know This Already?" quiz are found 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:

  • 8 or less overall score—Read the entire chapter. This includes the "Foundation Topics," "Foundation Summary," "Q&A," and "Scenarios" sections.

  • 9 or 10 overall score—Begin with the "Foundation Summary" section and then go to the "Q&A" and "Scenarios" sections at the end of the chapter. If you have trouble with these exercises, read the appropriate sections in "Foundation Topics."

  • 11 or 12 overall score—If you want more review on these topics, skip to the "Foundation Summary" section and then go to the "Q&A" and "Scenarios" sections at the end of the chapter. Otherwise, move to the next chapter.