BGP communities

Route-server BGP communities for ERA-IX.

Large BGP Communities

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.
For our members various BGP communities have been implemented to provide members with additional functionality over 'plain' BGP. All communities are of the 'large' type, allowing to transport information for/about both 16 and 32 bit ASNs.
To make use of BGP communities, make sure you have configured send-community towards our route-servers

Informational (tagged by ERA-IX)

These following communities are set by ERA-IX to tag information onto routes.

Horizon

Informative communities about Horizon route propagation.
Learn more: ERA-IX Horizon.

Community	Meaning	Description
`206221:899:x`	Originated at `x`	Location the route was learned from
`206221:900:x`	Permissive into `x`	Route has a permissive policy into `x`
`206221:901:x`	Participating into `x`	Route is participating into `x`

Location IDs

Locations for the communities above.

The Netherlands
ID	Location	Address
`18`	NIKHEF Housing	Science Park 105, Amsterdam
`62`	Equinix AM7	Kuiperbergweg 13, Amsterdam
`374`	Iron Mountain AMS-1	J.W. Lucasweg 35, Amsterdam
`1083`	NorthC Amsterdam	Kabelweg 48, Amsterdam
Germany
ID	Location	Address
`60`	Equinix FR5	Kleyerstrasse 90, Frankfurt
`12570`	Tornado DC	Robert-Bosch-Str. 25, Langen

Control (tagged by member)

Filtering

The filtering communities can be utilized by members to enforce peering policy. The filtering communities can be set to control where your route is going to be exported to. For example to de-peer a specific ASN present on the route-server.

Community	Purpose	Description
`206221:0:x`	Do not announce to member `x`	Selective de-peer ASN via route-server
`0:x`	Do not announce to member `x` (legacy)	Selective de-peer ASN via route-server.
`206221:0:0`	Do not announce to any member	De-peer all route-server peers.
`206221:1:x`	Announce to member x (override `206221:0:0`)	Override de-peer all ASNs for ASN.

ERA-IX advocates for open peering and exchanging of routes. However, when more advanced policy is desired, our communities will help to achieve this.
For example: A selective/restrictive peering policy can be enforced on the ERA-IX route-servers by setting the 206221:0:0 community along with the 206221:1:x for all member ASNs which should receive the route.
For legacy purposes we also allow selective de-peering through standard communities, these communities are only able to affect routes exported to 16-bit ASNs.

Horizon

Horizon control communities can be used to override portal-configured behavior for Horizon. Please note these communities do only affect exported routes.

Community	Purpose	Description
`206221:900:x`	Permissive towards facility `x`	(Upgrade portal disabled to permissive on prefix)
`206221:901:x`	Participate into facility `x`	(Upgrade portal disabled/override `206221:900:x`)
`206221:902:x`	Do not export route to facility `x`	Disable exporting of route to facility.

Prepending

Prepending communities can be used to selectively prepend routes. Allowing members to alter the flow of traffic from remote networks.

Community	Purpose	Description
`206221:101:x`	Prepend once to `x`	Apply selective prepend to specified ASN
`206221:121:x`	Prepend twice to `x`	Apply selective prepend (twice) to specified ASN
`206221:103:x`	Prepend thrice to `x`	Apply selective prepend (thrice) to specified ASN

These communities only affect routes exported by the ERA-IX route-servers, direct bilateral peering sessions will be unaffected by setting the prepending communities.