This chapter covers the following topics:
Introduction to BGP—Describes where and when to use BGP, as well as some basic BGP operations.
Connecting to the Internet with BGP—Describes multihoming and load sharing.
Synchronization—Describes what synchronization is and when to use it.
BGP States—Describes the five neighbor states for BGP.
This chapter details Border Gateway Protocol version 4 (BGP-4, referred to throughout this book as BGP). This chapter deals with the basic concepts and configuration commands of BGP, which are covered in greater complexity in Chapter 15, "BGP Neighbors." This chapter builds on your understanding of routing within large enterprise networks. This chapter introduces external BGP (eBGP) and familiarizes you with the necessary terms and concepts.
This chapter deals with how BGP works theoretically. Implementing and managing a BGP network is described in Chapter 15.
The purpose of the "Do I Know This Already?" quiz is to help you decide what parts of this chapter to use. If you already intend to read the entire chapter, you do not necessarily need to answer these questions now.
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 14-1 outlines the major topics discussed in this chapter and the "Do I Know This Already?" quiz questions that correspond to those topics.
|Foundation Topics Section||Questions Covered in This Section||Score|
|Introduction to BGP||1–5|
|Connecting to the Internet with BGP||6–7|
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 this question wrong for purposes of the self-assessment. Giving yourself credit for an answer you correctly guess skews your self-assessment results and might provide you with a false sense of security.
|1.||Which of the following are key features of BGP?
|2.||Which of the following best describes the routers that utilize eBGP to communicate with each other?
|3.||What is the transport protocol for BGP?
|4.||When are full routing updates sent in BGP?
|5.||Which of the following are BGP message types?
|6.||Place the BGP connection strategies in order from lowest to highest, in terms of memory and bandwidth requirements.
|7.||Place the BGP connection strategies in order from lowest to highest, in terms of likelihood to take the best path.
|8.||The synchronization rule is best described by which of the following?
|9.||Which of the following are benefits of enabling BGP synchronization?
|10.||Place the BGP states in order, from startup to peering.
|11.||Ideally, the output of the show ip bgp neighbors command will display what?
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: