From: Salvador Bertenbreiter <salvadorb@gmail.com>
Sent: Wednesday, January 7, 2026 5:54 PM
To: routing-wg@ripe.net
Subject: [routing-wg] Techniques to influence inbound (download) traffic across multiple IXPs with /24 prefixes

Hi everyone,

Hope you’re doing well. I’d like to ask how you approach inbound traffic engineering (download traffic) when you’re connected to multiple IXPs (some local, some remote) and you only have small prefixes (e.g., /24), so announcing more/less specifics isn’t really an option.

In that scenario, what methods have worked for you besides simple AS-path prepending (e.g., no prepend on local IX, prepend 1 on the closest remote IXP, prepend 2 on the next, etc.)?

Thanks in advance for any guidance or real-world examples.

Hi Salvador!

As Gert said: avoid “remote” peerings.

If you really need the remote peerings you probably want to connect to a specific peer. So do not peer with the IX route server but only peer bilateral with the important AS. (Or use the BGP communities of the IX route servers to “no-announce” or “prepend” your prefix selectively to certain peers”).

Regards

Klaus

[1] For example: AMS-IX Router Servers offer these communities: https://www.ams-ix.net/ams/documentation/ams-ix-route-servers