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What Is an ASN?

15.07.2026 Netbudur
What Is an ASN?
Netbudur Blog Infrastructure, hosting and server guides

Internet ID Card: What is ASN (Autonomous System Number)?

Did you know that each of the gigantic networks that create the Internet is a self-confidence ID number?

Google, Netflix, Turkish Telecom or a big data center... These giant structures connected to the Internet do not get random place on the global network map. Each needs a formal ID number to promote itself to the rest of the internet and exchange data.

Here’s the unique ID number ASN (Autonomous System Number - Autonomous System Number) denir.

1. What is ASN? Let's Understand With The Simpleest Benze

The Internet is not a single network managed from a single center; tens of thousands of independent networks (i.e., Otonom Sistemlerin / Autonomous System - AS) consist of interconnection.

Let’s make a very simple benzoism to revitalize your eye:

  • IP Addresses: Your home address is like your door number.

  • Otonom Sistem (AS): Limits, laws and an internal management " ⁇ " or "City" gibidir.

  • ASN (Otonom System Number): The picture in the world map of the country or city international code and name (e.g.: TR, DE, US or telephone codes.

If a data package comes from a server in America and comes to your computer in Turkey, routers do not find the way to look at single home addresses (IPs). First of which country (i.e., which country (i.e. in which country (i.e. in which country) the data pack is first ASNThey calculate which country (from ASN) will send to the country. Once the data reaches the right ASN, then the routers in its own will be delivered to the final IP address.

2. How ASN Works and Why Is It Necessary?

router devices on the Internet cannot hold millions of IP addresses across the globe in one memory. Instead of blocking IP addresses (for example, in blocks IP addresses (for example, 192.168.1.0/24 as well as autonomous systems.

Each Autonomous System (AS) announced IP blocks with the internet world ASN Uses ID:

"Ben AS12345'I. I have the following IP addresses in my six. If you want to send me data, turn your route to me!"

BGP (Class Gateway Protocol) collects these announcements and removes a global map, which means that the network is connected to what network. Thus, the shortest way to target ASN easily finds.

3. ASN Types: General (Public) and Private (Private) ASN

As only in IP addresses, ASNs are divided into two based on the purpose of use:

  • Public (General) ASN: They are official numbers that can be referred to globally on the Internet and can see all over the world. If you are an internet service provider (ISP) or data center, and you have to use Public ASN if you will notice directly with your own IPs.

  • Private (Special) ASN: Only a company’s own network is the number that it uses closed to the outside world. They are not directed on the Internet. (Private ASN ranges are often 64512 - 65534 and 4200000000 - 4294967294 between).

4. Who Needs ASN Opening?

There is no need for an ordinary home user, a small website or a standard business. They are connected to the internet via ASN of a service provider (Turkish Telecom, Turkcell, Vodafone, etc.).

But in these cases you need to have your own ASN:

  1. Large Data Centers (Datacenter) and Hosting Companies: To manage your own IP blocks and install backuped internet lines (BGP).

  2. Internet Service Providers (ISP): To distribute internet to customers and exchange traffic directly with other operators (peering).

  3. Giant Corporate Companies and Banks: Large structures that aim zero downtime on their infrastructures, backup internet connections with multiple operators.

5. How to Get ASN?

ASNs can not be determined according to the head. Globally IANA (Internet Assigned Numbers Authority) is managed and allocated by regional internet registration organizations (RIR) distributed by continents.

  • European, Middle East and Central Asia RIPE NCC executed by

  • If you want to get an organization ASN in Turkey, it is necessary to refer to RIPE NCC or apply through an enterprise (LIR) with RIPE member.

  • During the application, you need to prove that your network will have at least two different independent networks (Multi-homed) BGP neighboring and have your own IP blocks.

Last Word: Architect of Infrastructure

In Summary ASNThe web is the official addressing and identification system, which allows you to work away and stablely from the mess, in the layout of the huge networks we call. If you want to manage your own IP blocks freely, install uninterrupted backup in your infrastructure and become an independent "player" in the internet world, your way definitely passes through getting your own ASN.

You can also contact our expert team for your professional network infrastructure, IP rental and ASN management processes, benefit from our corporate solutions!