An AS number (ASN) identifies your network on the internet. With your own ASN you announce your own IP space with BGP and choose which providers carry your traffic. In Europe, ASNs come from the RIPE NCC, through a sponsoring LIR.
What an ASN is
The internet is made of tens of thousands of networks, each with its own number. Routers use these numbers in BGP to tell each other which IP ranges they can reach. Our network, for example, is AS215120. Today new ASNs have 32-bit numbers, which is why they are often six digits long.
Who needs one
You need your own ASN when you want to connect your IP space to more than one other network, for example two transit providers, or a provider plus an internet exchange. This is called multihoming, and the RIPE NCC assigns ASNs for exactly this purpose. If you only use one provider, that provider can announce your space from its own ASN instead (see bring your own IP).
How the request works
End users cannot request resources from the RIPE NCC directly. A LIR (Local Internet Registry), which is a RIPE NCC member, sponsors the request and keeps the resources registered. The steps are:
| 1. Details | You send the registration details: company or person, address, contacts, and how you plan to connect. |
| 2. Agreement | You and the LIR sign the RIPE NCC sponsorship agreement. |
| 3. Identity check | RIPE requires an identity verification: business registration documents for companies, an ID check for private persons. |
| 4. Assignment | The RIPE NCC assigns the ASN, and you can set up your route objects and RPKI. |
What you need next to the ASN
An ASN alone does not carry traffic. You also need IP space to announce, for example a provider independent IPv6 /48, and at least one network that runs a BGP session with you.
Your ASN through Evolushost
We are a sponsoring LIR. Our ASN package costs €79.99 per year plus a one-time setup of €59.99 and includes an IPv6 /48. We handle the request with the RIPE NCC; you only complete the identity verification. You can then announce your resources from our network in Vienna and Berlin. Details on our RIPE LIR services page.