Autonomous System

Definition of Autonomous System

An Autonomous System (AS) is a collection of Internet Protocol (IP) networks and routers under the control of a single organization that presents a common and clearly defined routing policy to the internet. These systems are identified by a unique AS number assigned by the Internet Assigned Numbers Authority (IANA). ASes enable the organization to exchange routing information with other ASes using the Border Gateway Protocol (BGP).


The phonetic representation of the keyword ‘Autonomous System’ in the International Phonetic Alphabet (IPA) is: /ɔːˈtɒnəməs ˈsɪstəm/

Key Takeaways

  1. Autonomous Systems (AS) are independent networks that follow a specific set of routing policies and guidelines, allowing them to exchange routing information with other AS through a protocol called Border Gateway Protocol (BGP).
  2. Each AS is assigned a unique identification number, called the Autonomous System Number (ASN), which is used to distinguish it from other networks and allow for efficient information exchange.
  3. Autonomous Systems play a crucial role in the operation of the internet, as they serve as the building blocks that connect different networks and ensure data is routed between them reliably and efficiently.

Importance of Autonomous System

The technology term “Autonomous System” (AS) is important because it refers to a collection of IP networks and routers under the control of a single organization that present a common routing policy to the Internet.

In essence, it fosters efficient management, communication, and routing of data over the internet.

By employing a unique identification number known as the Autonomous System Number (ASN), AS enables seamless data transfer among multiple networks, ensuring reduced redundancy, and aids in maintaining an organized hierarchy in the global internet infrastructure.

Additionally, AS promotes stability in global routing, network fault isolation, and simplified administration for large networks, which ultimately contributes to better network performance and a consistent user experience.


An Autonomous System (AS) serves a crucial purpose in the realm of internet connectivity, communication, and stability. In essence, ASs are large-scale networks or collections of IP addresses that are controlled by a single organization or entity, such as Internet Service Providers (ISPs), universities, or large corporations. They play a pivotal role in enabling seamless connectivity between various networks on the internet.

One of the primary purposes of an AS is to establish and maintain routing policies and strategies, ensuring that the flow of internet traffic is effectively and efficiently managed. By facilitating the exchange of routing information between distinct ASs through the Border Gateway Protocol (BGP), they contribute to global routing decisions and the optimization of the overall internet communication infrastructure. Aside from managing routing policies, Autonomous Systems also offer advantages in terms of security, administrative control, and scalability.

By grouping IP addresses under a single network, network administrators can better enforce security policies and protect their systems from external threats. Moreover, ASs also allow organizations to have greater control over their internet resources, enabling them to optimize performance, manage internal traffic, and allocate bandwidth as needed. Furthermore, the existence of multiple ASs adds a level of redundancy and fault tolerance to the internet, ensuring the delivery of services even in the event of network or hardware failures.

In summary, Autonomous Systems are fundamental building blocks of a robust and interconnected internet landscape that caters to the evolving demands for resources and services.

Examples of Autonomous System

Self-Driving Cars: Companies like Tesla, Waymo (a subsidiary of Alphabet Inc., Google’s parent company), and Cruise have been working on developing autonomous vehicles that use advanced sensor technology, AI, and machine learning to navigate roads and traffic without human intervention. These self-driving cars can potentially reduce traffic congestion, decrease the number of accidents, and improve overall road safety.

Autonomous Drones: Drones are becoming increasingly autonomous, enabling their use in various industries besides entertainment and recreational purposes. Amazon is working on Prime Air, a drone-based delivery system designed to autonomously deliver small packages in under 30 minutes. Autonomous drones are also being used in agriculture, performing crop monitoring, pesticide spraying, and surveying tasks. Additionally, autonomous drones play a vital role in search and rescue operations, gathering data in hazardous environments or dangerous situations without risking human lives.

Robotics and Manufacturing: In manufacturing, autonomous robotic systems such as robotic arms and conveyor belts synchronized with AI algorithms are revolutionizing the industry landscape. Companies like Boston Dynamics and ABB Robotics are developing robots that can work autonomously to perform complex tasks, work alongside human workers, and adapt to changing environments. These autonomous robotic systems help enhance productivity, efficiency, and cost-effectiveness while reducing the risk of human error and injury in industrial setups.

Autonomous System FAQ

Q: What is an Autonomous System?

An Autonomous System (AS) is a collection of IP networks and routers under the control of a single organization that presents a common routing policy to the internet. ASes enable a clear separation between different routing domains and help to establish routing policies between them.

Q: How do Autonomous Systems communicate with each other?

Autonomous Systems communicate with each other using the Border Gateway Protocol (BGP). BGP is designed to allow routers to exchange information about the reachability of destination IP address prefixes and enforce routing policies. The BGP routers in each AS advertise routes to IP address prefixes that are reachable in their own AS or through other ASes.

Q: What is an Autonomous System Number?

An Autonomous System Number (ASN) is a unique identifier that is assigned to each Autonomous System. ASNs are used to identify the AS in BGP routing updates and play a crucial role in ensuring the correctness and stability of internet routing. ASNs are managed by the Internet Assigned Numbers Authority (IANA) and are typically allocated to organizations by their local Regional Internet Registry (RIR).

Q: How are Autonomous Systems classified?

Autonomous Systems are classified into two types based on their role in the global internet routing system: Stub AS and Transit AS. A Stub AS is an AS that only connects to one other AS and has no transit traffic passing through it. A Transit AS, on the other hand, connects to multiple ASes and allows traffic from one AS to pass through it to reach another AS.

Q: What are the benefits of using Autonomous Systems?

Autonomous Systems provide several benefits, including administrative control, routing policy enforcement, scalability, and fault isolation. By dividing the internet into multiple ASes, organizations can maintain control over their own routing policies and ensure that they are applied consistently throughout their network. Furthermore, ASes help to improve the scalability of internet routing by reducing the complexity of routing tables and processing overhead on routers.

Related Technology Terms

  • Artificial Intelligence (AI)
  • Robotics
  • Self-driving vehicles
  • Internet of Things (IoT)
  • Machine learning (ML)

Sources for More Information


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