Hello everyone,
Now I’d like to share with you BGP
What is an Autonomous System?
An Autonomous System (AS) is a group of Internet Protocol (IP) networks that are controlled by one entity, typically an Internet service provider (ISP), and have the same routing policy. Each AS is assigned a unique AS number, which identifies an AS on a BGP network. Two types of AS numbers are available: 2-byte AS numbers and 4-byte AS numbers. A 2-byte AS number ranges from 1 to 65535, and a 4-byte AS number ranges from 1 to 4294967295. Devices supporting 4-byte AS numbers are compatible with devices supporting 2-byte AS numbers.
BGPClassification
There are two device roles in BGP message exchange:
Speaker
Peer
BGP RouterID
The BGP router ID of a device must be unique on a BGP network.It can be manually configured or selected from IPv4 addresses on the device. Bydefault, an IPv4 address of a loopback interface on a device is used as the BGProuter ID. If no loopback interface is configured on the device, the systemselects the largest IPv4 address from all IPv4 addresses of interfaces as theBGP router ID. Once the BGP router ID is selected, the system retains thisrouter ID even if a larger IPv4 address is configured on the device later. Thesystem changes the BGP router ID only when the corresponding IPv4 address isdeleted.
This is what I want to share with you today, thank you!
