BGP by Beijnum, Iljitsch van -- Read -- Imperial Library of Trantor

Index

BGP

SPECIAL OFFER: Upgrade this ebook with O’Reilly Preface

Intended Audience What’s in This Book? How to Read This Book Conventions Used in This Book How to Contact Us Acknowledgments

1. The Internet, Routing, and BGP

Topology of the Internet

The NSFNET Backbone Commercial Backbones and NAPs The Rest of the World Transit and Peering Classification of ISPs

TCP/IP Design Philosophy

The IP Protocol The Routing Table

Routing Protocols Multihoming

2. IP Addressing and the BGP Protocol

IP Addresses

Subnetting and VLSM CIDR: Classless Inter-Domain Routing

Interdomain Routing History The BGP Protocol

Open Message Update Message Notification and Keepalive Messages BGP States Propagation of BGP Routes How BGP Selects Routes

The route-selection algorithm BGP tie-breaking rules

Multiprotocol BGP

Routing Multicast IPv6 MBGP and MPLS VPNs

Interior Routing Protocols

RIP IGRP and EIGRP OSPF IS-IS Interaction Between Routing Protocols

3. Physical Design Considerations

Availability

Single points of failure Common sense Testing

Selecting ISPs Bandwidth

Minimum Bandwidth Required Burst Bandwidth and Queuing Delays Calculating Bandwidth, Step by Step

Router Hardware

Host-Based Routers Multilayer Switches Memory and the Routing Table Performance Anticipating Growth

Failure Risks

Water Power Failure

Building a Wide Area Network

The Likelihood of Concurrent Fiber Cuts

Network Topology Design

A Design Model The Topology

4. IP Address Space and AS Numbers

The Different Types of Address Space

Provider-Independent Address Space Your Own Provider Aggregatable Block Address Space From an ISP

Requesting Address Space Renumbering IP Addresses The AS Number Routing Registries Routing Policy Specification Language

5. Getting Started with BGP

Enabling BGP

How to Announce an Address Block Configuring the Router

Monitoring BGP Clearing BGP Sessions

Soft Reconfiguration Inbound Route Refresh

Filtering Routes

Filter Lists Distribute Lists Prefix Lists

Internal BGP

Enabling iBGP Default Routes Next Hop Processing Synchronizing with the IGP

The Internal Network

Cisco’s Hot Standby Routing Protocol Full BR2 Configuration RPSL Routing Policy

Minimizing the Impact of Link Failures eBGP Multihop

6. Traffic Engineering

Knowing Which Route Is Best

Finding High- and Low-Quality Routes Is the Highest-Bandwidth Route Best?

Route Maps Setting the Local Preference Manipulating Inbound AS Paths Inbound Communities

RPSL Routing Policy

BGP Load Balancing Traffic Engineering for Incoming Traffic Setting the MED

Prepending Outbound AS Paths The Effect of AS Path Prepending Setting Outbound Communities

Well-known communities Common community actions

Influencing the Local Preference in Upstream ASes Prepending the AS Path

Announcing More Specific Routes Queuing, Traffic Shaping, and Policing

TCP Congestion Control

Slow start Congestion avoidance Fast retransmit and fast recovery

TCP Under Packet Loss and Delay Conditions Queuing

First in, first out Weighted fair queuing Random early detect Priority queuing Custom queuing

Traffic Shaping and Rate Limiting

7. Security and Integrity of the Network

Passwords and Security

Telnet Versus SSH

Software

Software Lifecycle Cisco IOS Versions

Protecting BGP

Avoiding Black Holes

Denial-of-Service Attacks

Identifying Attacking Packets Tracking Down and Stopping the Source Filtering DoS Traffic Rate-Limiting DoS Traffic Deflecting DoS Traffic Using BGP

8. Day-to-Day Operation of the Network

The Network Operations Center

The NOC and the Help Desk Contacting the NOC

NOC Hardware Facilities SNMP Management

Network-Management Suites Product-Specific Management Software Generic SNMP Tools MRTG BGP-4 Management Information Base

Router Names General IP Network Management

Logging Version Control The Network Time Protocol Scheduled Reloads

9. When Things Start to Go Down: Troubleshooting

Keeping a Clear Head Managing the Troubleshooting Process Dealing with Service Providers Physical and Datalink Layer Problems

Broken Cable or Circuit

Link status and keepalives Last input and loops Line encoding and framing

Power and Equipment Failure Poor Network Performance

Too much traffic High CPU load Ethernet collisions, broadcasts, and loops Too many errors CRC errors on ATM Ethernet errors because of duplex or speed mismatch

Routing and Reachability Problems

BGP Session Is Down BGP Session Is Unstable Address Blocks Aren’t Announced Filters Further Upstream Outgoing Traffic Not Going Out

Black Holes

Is the Black Hole Incoming or Outgoing? Transit from Nontransit AS Traffic Is Filtered Broken Upstream AS Announcing Your Routes—With a Vengeance

DNS Problems

10. BGP in Larger Networks

Peer Groups Using Loopback Addresses for iBGP iBGP Scaling

Route Reflectors Confederations

Dampening Route Flaps OSPF as the IGP

Redistributing Routing Information

Redistributing static and connected into OSPF Redistributing BGP into OSPF Redistributing OSPF into BGP Redistributing BGP into OSPF into BGP Redistributing static and connected routes into BGP

Traffic Engineering in the Internal Network Network Partitions

IP Tunnels and Path MTU Discovery

11. Providing Transit Services

Route Filters Communities

Setting the Local Preference Fine-Grained Path Prepending Setting Communities on Incoming Routes Community Overview In Routing Registry

Anti-DoS Measures

A Community for Black-Holing Preemptive Anti-DoS Measures

Customers with Backup Connections

Simple Backups More Complex Backups: BGP

Providing IPv6 and Multicast

IPv6 Multihoming Multicast

12. Interconnecting with Other Networks

Peering Internet Exchanges, NAPs, and MAEs Connecting to an Internet Exchange

The Business of Peering Where Does the Traffic Go? The Politics of Peering Multilateral Peering Connecting to the Exchange

Connecting to More Exchange Points Rejecting Unwanted Traffic IX Subnet Problems Talking to Other Network Operators Exchange Point Future

A. Cisco Configuration Basics

IP Configuration Essentials

Source Routing and Directed Broadcasts Antispoofing Filters CIDR and VLSM

B. Binary Logic, Netmasks, and Prefixes C. Notes on the IPv4 Address Space Glossary Index About the Author Colophon SPECIAL OFFER: Upgrade this ebook with O’Reilly

← Prev
Back
Next →

← Prev
Back
Next →