BGP Communities

BGP communities which you can use for traffic engineering.

BGP communities in general provide an in-band mechanism to provide additional information along with routes announced through BGP. This information can be used for administrative but also technical purposes, such as route-filtering, prepending and preferring.

Traffic Engineering

At AS35133 we provide communities to allow customers to manage their traffic, our communities use the following logic to influence routing.

  • Do not export: 35133:0:0
  • Export to ASN: 35133:1:[ASN]
  • Do not export to ASN: 35133:0:[ASN]
  • Prepend 1x to ASN: 35133:101:[ASN]
  • Prepend 2x to ASN: 35133:102:[ASN]
  • Prepend 3x to ASN: 35133:103:[ASN]

For internet exchanges we use the route-server to refer to the entire internet exchange, more specifics are available for direct peering sessions. Route-server communities will be passed through to the exchange. So the internet exchanges’ communities can be used as well. Example for ERA-IX here.

Upstreams

Our network currently has the following upstreams.

Upstream ASN Availability
Arelion AS1299 Amsterdam
Cogent AS174 Amsterdam
Liberty Global AS6830 Amsterdam
ERA-IX Amsterdam AS206221 Amsterdam
ERA-IX Frankfurt AS213687 Frankfurt

Examples

  • Do not export to AS174 (Cogent): 35133:0:174
  • Export to AS174: 35133:1:174 (override 35133:0:0)
  • Prepend 1x to AS174 (Cogent): 35133:101:174
  • Don’t export to ERA-IX: 35133:0:206221
  • Export to ERA-IX 35133:1:206221 (override 35133:0:0)

Last updated 20 February 2025

Was this article helpful?

Related articles