BGP Communities

Traffic over the NL-ix Route Server can be managed via BGP communities or the Route Server Configurator (filter.nl-ix.net). Please note that you should make a choice for either the communities or the GUI of the Route Server Configurator. Using both may result in unexpected behaviour. The GUI will not show any communities that are set manually.

BGP communities:

With BGP communities you can control which routes sent to the Route Servers are announced to other peers. If no community tags are specified, routes are advertised to all peers by default.

Routes are marked with standard communities (16-bit ASNs) or extended communities (16-bit and 32-bit ASNs).

Traffic over the NL-ix Route Server can be managed with the following communities:

Action Communities
Action BGP communities have direct impact on your routing policy. Setting action tags changes the way prefix announcements are handled.

* Only one of standard or extended BGP communities has to be applied
** Prefixes marked with this community are not redistributed to Route Server peers
*** Route Server selects another instance of prefix. If none available this one goes to peers. Requires them to match on community as well

Prepending
Prepending makes the route you advertise over the Route Server less attractive. Other routes (like your IP-transit upstream) may be preferred

Actions per region

Informational Communities
Informational BGP communities pass on information about how and where a route was learned. The marks are assigned by the Route Servers. Each prefix received from Route Servers is marked with various communities.