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Autonomous System Numbers

An Autonomous System (AS) is a group of IP networks run by one or more network operators with a single, clearly defined routing policy.

When exchanging exterior routing information, each AS is identified by a unique number: the Autonomous System Number (ASN). An AS is also sometimes referred to as a routing domain.

Current guidelines require a network to be multi-homed, and have a unique routing policy for an ASN to be assigned. Requests must show the routing policy of the AS.

Any organisation can acquire an ASN. This requires a contractual agreement with a sponsoring LIR or with the RIPE NCC.

To do this you need to find a sponsoring LIR or you can become a Direct Assignment User.

Requesting AS Numbers

As a member of the RIPE NCC, you would have access to the LIR Portal, this provides an easy and secure way to request resources. Direct Assignment Users do not get access to the LIR Portal. They will have to request resources by email.