Border Gateway Protocol Ipv4 (Bgpv4); Autonomous Systems (As) - Dell C9000 Series Networking Configuration Manual

Border Gateway Protocol IPv4
This chapter provides a general description of BGPv4 as it is supported in the Dell Networking OS.
BGP protocol standards are listed in the
BGP is an external gateway protocol that transmits interdomain routing information within and between
autonomous systems (AS). The primary function of the BGP is to exchange network reachability information
with other BGP systems. BGP generally operates with an internal gateway protocol (IGP) such as open
shortest path first (OSPF) or router information protocol (RIP), allowing you to communicate to external ASs
smoothly. BGP adds reliability to network connections by having multiple paths from one router to another.
Topics:
•

Autonomous Systems (AS)

• Sessions and Peers
• Route Reflectors
• BGP Attributes
• Multiprotocol BGP
• Implement BGP
• Configuration Information
• BGP Configuration
• Enabling MBGP Configurations
• BGP Regular Expression Optimization
• Debugging BGP
• Sample Configurations
Autonomous Systems (AS)
BGP autonomous systems (ASs) are a collection of nodes under common administration with common
network routing policies.
Each AS has a number, which an internet authority already assigns. You do not assign the BGP number.
AS numbers (ASNs) are important because the ASN uniquely identifies each network on the internet. The
Internet Assigned Numbers Authority (IANA) has reserved AS numbers 64512 through 65534 to be used for
private purposes. IANA reserves ASNs 0 and 65535 and must not be used in a live environment.
You can group autonomous systems into three categories (multihomed, stub, and transit), defined by their
connections and operation.
Standards Compliance chapter.

Border Gateway Protocol IPv4 (BGPv4)

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