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
