Definitions[]
An Autonomous System Number (ASN) is
“ | [a] unique 16 bit number assigned by the InterNIC that refers to a particular collection of networks under a common administration and sharing a common routing strategy.[1] | ” |
“ | identifies the autonomous system — networks using the same, specified routing policy — and enables the autonomous system to exchange information with other autonomous systems.[2] | ” |
Overview[]
Autonomous System Numbers are used by various routing protocols. AS numbers are assigned to the Regional Internet Registries by the IANA.