Reassigning AS Numbers

The RIPE NCC has a large supply of returned 16 and 32-bit Autonomous System (AS) Numbers that are referenced in RIPE Database objects. With the global supply of 16-bit AS Numbers becoming exhausted, there is a clear need for these resources from some operators.

What Are These References?

These AS Numbers are referenced in a number of objects - mostly other AS Number objects in the policy statements of the "import:" and "export:" attributes and various set objects. We have also found a handful of route objects which don't originate from these returned AS Numbers but reference them in other attributes. Detailed analysis shows that around 4,000 objects are referencing these 1,900 AS Numbers.

What's The Next Step? 

Based on feedback received from the RIPE community, we are currently in the process of cleaning up these references and reassinging the ASNs. As discussed with the community, the RIPE NCC will be taking the following actions: 

  • We will send an email to the maintainer and contacts of the RIPE Database objects in which the returned AS Numbers are referenced, asking for the reference to be removed
  • We will send three additional reminders, at three week intervals, for a total of four emails
  • If the reference is still in place after four emails, we will update the RIPE Database object and remove the reference ourselves
  • If the reference is recreated within one month of deletion (possibly due to automatic updates), we will contact the organisation through means of communication other than email

What Can You Do To Help?

The best way for this to be cleaned up is for the maintainers of these objects to remove the references themselves. Because many of these objects are generated automatically, we can't just remove these references with a bulk update, as the next time the object is generated the references will return. To fix this, the maintainers need to update any templates or scripts that generate the objects.

If one of your objects references a returned AS Number, you will soon receive an email from the RIPE NCC. In this email we will list which of your objects references which returned AS Number. When you receive such a mail, please remove the references and change any software you have that automatically generates your objects. Your help will mean there are more 16-bit AS Numbers available for use by the RIPE community.