Definition
Autonomous System
An Autonomous System (AS) is a cohesive group of IP networks and routers under the control of a single entity, characterised by a unified routing policy when interacting with other Autonomous Systems on the Internet. Each AS is uniquely identified by an Autonomous System Number (ASN), facilitating global routing decisions through protocols like the Border Gateway Protocol. This structure enables the Internet to efficiently route traffic between vast, diverse networks by segmenting them into manageable, policy-driven units.