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What is an autonomous system (ASN)?

You’ve probably heard of terms like AS, ASN and BGP. But do you know what each one means? And how do they work together to maintain the internet? In this article, we’ll explain the general concepts of each term, as well as how to become an autonomous system.

The Internet is a global network of interconnected networks. In order for different networks to communicate with each other, they need to be interconnected via routers and other network devices. A single organization or entity manages and operates these networks, called autonomous systems (AS). Each autonomous system has a unique identity and a set of distinct routing policies.

The Border Gateway Protocol (BGP) is the routing protocol used by autonomous systems to exchange information with each other. A dynamic routing protocol designed to exchange routing information between different autonomous systems is BGP.

What’s the relationship with BGP?

The function of BGP is to allow each autonomous system to share up-to-date routing information with other autonomous systems. In this way, it makes it possible to route network traffic efficiently and reliably over the Internet. When an autonomous system needs to forward traffic to another AS, it consults the BGP routing tables to determine which is the best route to take.

ASs work by establishing physical and logical connections between network devices. Each has a set of IP address prefixes assigned to it, which are used to define its routing policies and decide how to forward network traffic to other autonomous systems.

The importance of autonomous systems and BGP lies in the ability to interconnect different networks, enabling efficient and reliable routing of network traffic across the Internet. Without these elements, communication between different networks would be much more difficult and prone to failure.

How to become an autonomous system (ASN)?

What is ASN? How to become an ASN?

In order to obtain an autonomous system, you need to request an Autonomous System Number (ASN) from the Regional Internet Registry (RIR) corresponding to the region in which the organization is located. In addition, network devices must be configured according to the routing policies that the organization has defined. To use BGP, the protocol must be configured on each of the network devices that interconnect the autonomous systems.

How important are ASNs?

The ASN is fundamental to the functioning of the global Internet. They allow different networks to connect and communicate with each other, forming a single global network that covers the whole world.

Each AS is responsible for managing traffic routing within its own network, as well as to other autonomous systems. Autonomous systems determine how to forward network traffic and which paths are preferred for different types of traffic through the routing policies they define.

BGP, which is the routing protocol used by autonomous systems to exchange routing information with each other, is crucial to ensuring that traffic is forwarded efficiently and reliably over the Internet. The Internet would be fragmented into isolated networks without the presence of BGP and autonomous systems. In addition, communication between different parts of the world would be much more difficult.

In this way, autonomous systems allow companies and organizations to manage their own networks independently. You can then establish your own security, connectivity and traffic control policies. Therefore, this allows companies and organizations to have greater control over their network infrastructure and ensure that it meets their specific needs.

In short, SAs are fundamental to the functioning of the global Internet. They enable communication between different networks and ensure that network traffic is routed efficiently and reliably.

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