Posted On: Nov 17, 2023

Today, AWS announced the launch of a new IPAM feature called Bring-Your-Own-ASN (BYOASN) that lets you bring your own Autonomous System Number (ASN) to AWS, and use it to advertise your IP addresses from AWS. If your applications are using trusted IP addresses and ASNs that your partners or customers have allow listed in their network, you can now run these applications in AWS without requiring your partners or customers to change their allow lists. 

The reachability of many workloads, such as email, host-managed VPNs, and proxies, are tied to an organization’s IP address, which you can retain in AWS when you bring your IP addresses to AWS using Bring-Your-Own-IP (BYOIP). For some workloads, the reachability is tied to both, your IP address and your Autonomous System Number (ASN), which are unique identifiers assigned by Internet Registries to your network. Now, with IPAM, you can bring your own ASN to AWS to advertise your BYOIP addresses. When you use BYOASN, the traffic originating from your IP address carries your ASN as the source ASN, instead of the AWS ASN. With that, your workloads remain reachable even by your customers or partners that have allow listed both, your IP address, and your ASN.

The BYOASN feature is available in IPAM in all AWS Regions, except China (Beijing, operated by Sinnet), and China (Ningxia, operated by NWCD). 

To learn more about this feature, view the service documentation. For details on IPAM pricing, refer to the IPAM tab on the Amazon VPC Pricing page.