1
© 2005 Cisco Systems, Inc. All rights reserved.
Session Number
Presentation_ID
Cisco Confidential
APNIC 22
BGP Tutorial
Philip Smith
<pfs@cisco.com>
APNIC 22
4th-8th September 2006
Kaohsiung, Taiwan
2
© 2006 Cisco Systems, Inc. All rights reserved.
APNIC 22
Tutorial Outline
• Part 1
Introduction to BGP
Coffee Break
• Part 2
Deploying BGP
Lunch
• Part 3
Multihoming
Coffee Break
• Part 4
Troubleshooting
3
© 2006 Cisco Systems, Inc. All rights reserved.
APNIC 22
Presentation Slides
• Are available on
ftp://ftp-eng.cisco.com
/pfs/seminars/APNIC22-BGP-part1+2.pdf
And on the APNIC 22 website
• Feel free to ask questions any time
4
© 2006 Cisco Systems, Inc. All rights reserved.
APNIC 22
BGP Techniques for Internet Service
Providers
• BGP Basics
• Scaling BGP
• Using Communities
• Deploying BGP in an ISP network
5
© 2005 Cisco Systems, Inc. All rights reserved.
Session Number
Presentation_ID
Cisco Confidential
APNIC 22
BGP Basics
What is this BGP thing?
6
© 2006 Cisco Systems, Inc. All rights reserved.
APNIC 22
Border Gateway Protocol
• Routing Protocol used to exchange routing information between
networks
exterior gateway protocol
• Described in RFC4271
RFC4276 gives an implementation report on BGP-4
RFC4277 describes operational experiences using BGP-4
• The Autonomous System is BGP’s fundamental operating unit
It is used to uniquely identify networks with common routing
policy
7
© 2006 Cisco Systems, Inc. All rights reserved.
APNIC 22
Autonomous System (AS)
• Collection of networks with same routing policy
• Single routing protocol
• Usually under single ownership, trust and administrative
control
• Identified by a unique number
AS 100
8
© 2006 Cisco Systems, Inc. All rights reserved.
APNIC 22
Autonomous System Number (ASN)
• An ASN is a 16 bit number
1-64511 are assigned by the RIRs
64512-65534 are for private use and should never appear on
the Internet
0 and 65535 are reserved
• 32 bit ASNs are coming soon
www.ietf.org/internet-drafts/draft-ietf-idr-as4bytes-12.txt
With AS 23456 reserved for the transition
9
© 20