AS286 Communities
v20201104

Fading away ...

AS286/KPN International was taken over by AS3257/GTT in December 2019. AS286 will be integrated into / migrated to 3257 and fade away. Therefore some of the information found on these pages might be outdated / obsolete.

Introduction

This document only applies to the KPN International IP backbone AS286.

The hereby described communities may be adjusted, altered and updated any time. Even our processes cover updates to documentation, there's no guarantee, that it's always up-to-date. In case of doubt, transit customers should contact our NOC and peers (if any left) should contact peering@as286.net

A general description on routing policies of AS286 can be found here https://as286.net/AS286-routing-policy.html.

The "standard" communities (supported for peers as well)

Please note that the use of GSHUT (BGP graceful shutdown) will be monitored and must not be used for traffic engineering purposes. We'll remove support (on a per peer basis) for GSHUT if we observe frequent - non-maintenance related - use of this community.
Customers should be aware, that sBH/erBH and rtsdCoS received announcements will remain active with a higher local-pref (status 20171115, but might change).

ENG: (selective) Blackhole traffic and change CoS behavior (transit customers only)

Transit customers are only allowed to tag prefixes (or more specifics of them) of address space registered with an IRR and visible through whois.radb.net under his AS-set. Tagged prefixes will not be advertised to any other peer or customer and not (yet) to other peers or IX blackhole services (nor whatever comes rtsdCoS close).

ENG: Local preference (transit customers only)

Routes of customer will get a standard local preference of 100 assigned. (FYI: peering routes are usually between 50 and 90.)

ENG: Prepending / suppressing AS286 announcements (transit customers only)

Transit customer can suppress or prepend announcements of their prefixes through AS286 on any other direct BGP session KPN operates.

If a prefix is tagged with multiple prepend communities and if those are applicable for the announcement, only ONE prepend community will be used (no accumulation) and the standard ones will be leading, an AS specific will take precedence over an IX over a regional one and a do-not-announce over do-not-prepend over prepend-once over prepend-twice over triple-prepend over quad-prepend.

Regional communities

A "peer" in this context is a BGP sessions between AS286 and another AS, exchanging customer (or partial) routes only - BGP sessions to customers of KPN on which KPN does provide transit, are NOT included.

Exchange related communities

Announcements on the following public Exchanges KPN is present can be suppressed or prepended with the following communities:

AS specific communities

Announcement can also be suppressed or prepended to any AS (peer or customer) KPN has a direct BGP session. Due to 32bit AS numbers (ASN - luckily the Internet got them), some "basic" math is needed, at least for 32bit ASN ... In the following table,
    d stands for ASN >> 16 (or ASN / 65536)
    asmod for ASN & 0xffff (or ASN % 65536)
In words: d is the quotient of the ASN divided by 65536 and asmod the remainder of it. This works out for all currently allocated ASN (d<=6) and 65535:666 is also pretty far away.

This reads more complicated than it is: for 16bit ASN (<65536), d=0 and asmod is simply the ASN. E.g. if you want have your prefixes prepend once on the BGP session of AS286 to AS3320, just tag your prefix with 65001:3320.

Again, for 16bit ASN this is quite simple

Other legacy communities for suppressing or prepending announcements are not supported anymore (286:21-24,29; 286:37-39 and all the legacy to AS mapped communities 286:100-286:299).

INF: Route type (not settable)

AS286 tags routes internally based on their type (customer, peer, IX, PI, "full" PA block, more specific, static, interface, IGP, .... some of those communities can only be seen on AS286 Looking Glass or RouteServer, as prefixes tagged with them might never be announced to eBGP peers.

Some of the listed communities are classified as legacy (LG) and will vanish soon or later in AS286.

INF: Route origin (not settable)

AS286 tags prefixes learned with regional, country and city (KPN PoP) information where the PE is located. Countries follow the notation 286:(3000+E.164) notation (unless there's a clash with other used communities), cities are "somewhere" between 286:4000 and 286:46xx ... The PoP names are KPN notation.

INF: Misc communities (not settable)

Some additional communities might be seen, which are purely internal "functional" communities ... not all of them will be explained here, but if you miss one and need information about it, please contact us.