BGP: Building Reliable Networks with the Border Gateway Protocol

by Iljitsch van Beijnum

Overview

Border Gateway Protocol (BGP) is the routing protocol used to exchange routing information across the Internet. It makes it possible for ISPs to connect to each other and for end-users to connect to more than one ISP. BGP is the only protocol that is designed to deal with a network of the Internet's size, and the only protocol that can deal well with having multiple connections to unrelated routing domains.This book is a guide to all aspects of BGP: the protocol, its configuration and operation in an Internet environment, and how to troubleshooting it. The book also describes how to secure BGP, and how BGP can be used as a tool in combating Distributed Denial of Service (DDoS) attacks. Although the examples throughout this book are for Cisco routers, the techniques discussed can be applied to any BGP-capable router.The topics include:

• Requesting an AS number and IP addresses
• Route filtering by remote ISPs and how to avoid this
• Configuring the initial BGP setup
• Balancing the available incoming or outgoing traffic over the available connections
• Securing and troubleshooting BGP
• BGP in larger networks: interaction with internal routing protocols, scalability issues
• BGP in Internet Service Provider networks

The book is filled with numerous configuration examples with more complex case studies at the end of the book to strengthen your understanding. BGP is for anyone interested in creating reliable connectivity to the Internet.

Product Details

ISBN-13:	9781449390822
Publisher:	O'Reilly Media, Incorporated
Publication date:	09/11/2002
Sold by:	Barnes & Noble
Format:	eBook
Pages:	290
File size:	3 MB

About the Author

Iljitsch van Beijnum has been working with BGP in ISP and end-user networks since 1996. He has configured the protocol on single-router networks; networks with several hundred Ciscos ranging from the slowest to the fastest available; and multivendor environments with BGP running on Cisco and Juniper routers, Extreme switches, and FreeBSD hosts running GNU Zebra

Table of Contents

Preface; Intended Audience; What’s in This Book?; How to Read This Book; Conventions Used in This Book; How to Contact Us; Acknowledgments; Chapter 1: The Internet, Routing, and BGP; 1.1 Topology of the Internet; 1.2 TCP/IP Design Philosophy; 1.3 Routing Protocols; 1.4 Multihoming; Chapter 2: IP Addressing and the BGP Protocol; 2.1 IP Addresses; 2.2 Interdomain Routing History; 2.3 The BGP Protocol; 2.4 Multiprotocol BGP; 2.5 Interior Routing Protocols; Chapter 3: Physical Design Considerations; 3.1 Availability; 3.2 Selecting ISPs; 3.3 Bandwidth; 3.4 Router Hardware; 3.5 Failure Risks; 3.6 Building a Wide Area Network; 3.7 Network Topology Design; Chapter 4: IP Address Space and AS Numbers; 4.1 The Different Types of Address Space; 4.2 Requesting Address Space; 4.3 Renumbering IP Addresses; 4.4 The AS Number; 4.5 Routing Registries; 4.6 Routing Policy Specification Language; Chapter 5: Getting Started with BGP; 5.1 Enabling BGP; 5.2 Monitoring BGP; 5.3 Clearing BGP Sessions; 5.4 Filtering Routes; 5.5 Internal BGP; 5.6 The Internal Network; 5.7 Minimizing the Impact of Link Failures; 5.8 eBGP Multihop; Chapter 6: Traffic Engineering; 6.1 Knowing Which Route Is Best; 6.2 Route Maps; 6.3 Setting the Local Preference; 6.4 Manipulating Inbound AS Paths; 6.5 Inbound Communities; 6.6 BGP Load Balancing; 6.7 Traffic Engineering for Incoming Traffic; 6.8 Setting the MED; 6.9 Announcing More Specific Routes; 6.10 Queuing, Traffic Shaping, and Policing; Chapter 7: Security and Integrity of the Network; 7.1 Passwords and Security; 7.2 Software; 7.3 Protecting BGP; 7.4 Denial-of-Service Attacks; Chapter 8: Day-to-Day Operation of the Network; 8.1 The Network Operations Center; 8.2 NOC Hardware Facilities; 8.3 SNMP Management; 8.4 Router Names; 8.5 General IP Network Management; Chapter 9: When Things Start to Go Down: Troubleshooting; 9.1 Keeping a Clear Head; 9.2 Managing the Troubleshooting Process; 9.3 Dealing with Service Providers; 9.4 Physical and Datalink Layer Problems; 9.5 Routing and Reachability Problems; 9.6 Black Holes; 9.7 DNS Problems; Chapter 10: BGP in Larger Networks; 10.1 Peer Groups; 10.2 Using Loopback Addresses for iBGP; 10.3 iBGP Scaling; 10.4 Dampening Route Flaps; 10.5 OSPF as the IGP; 10.6 Traffic Engineering in the Internal Network; 10.7 Network Partitions; Chapter 11: Providing Transit Services; 11.1 Route Filters; 11.2 Communities; 11.3 Anti-DoS Measures; 11.4 Customers with Backup Connections; 11.5 Providing IPv6 and Multicast; Chapter 12: Interconnecting with Other Networks; 12.1 Peering; 12.2 Internet Exchanges, NAPs, and MAEs; 12.3 Connecting to an Internet Exchange; 12.4 Connecting to More Exchange Points; 12.5 Rejecting Unwanted Traffic; 12.6 IX Subnet Problems; 12.7 Talking to Other Network Operators; 12.8 Exchange Point Future; Cisco Configuration Basics; IP Configuration Essentials; Binary Logic, Netmasks, and Prefixes; Notes on the IPv4 Address Space; Glossary; Colophon;