Autonomous System

What Does Autonomous System Mean?

An autonomous system (AS) is a network or a collection of networks that are all managed and supervised by a single entity or organization.

Advertisements

An AS is a heterogeneous network typically governed by a large enterprise. An AS has many different subnetworks with combined routing logic and common routing policies. Each subnetwork is assigned a globally unique 16 digit identification number (known as the AS number or ASN) by the Internet Assigned Numbers Authority (IANA).

Techopedia Explains Autonomous System

Autonomous systems were introduced to regulate organizations such as Internet service providers (ISP), educational institutions and government bodies. These systems are made up of many different networks but are operated under the umbrella of a single entity for easy management. Large enterprises tend to have large network infrastructures with many smaller networks, dispersed geographically but connected using a similar operating environment.

Border Gateway Protocol (BGP) is the protocol that addresses the routing of packets among different autonomous systems to connect them. BGP uses the ASN to uniquely identify each system. This is particularly important when routing and managing routing tables for external networks or autonomous systems around their borders.

Autonomous systems numbered one to 64511 are available by IANA/ARIN (IANA/American Registry for Internet Numbers) for global use. The 64512 to 65535 series is reserved for private and reserved purposes.

Advertisements

Related Terms

Margaret Rouse

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.