# Routing Beacons

A Routing Beacon or BGP Beacon is a Border Gateway Protocol (BGP) speaker that announces and withdraws a particular prefix at predetermined time intervals. RIS Route Collectors originate a small number of routing beacons. These serve to better understand the state of the global BGP Internet routing system, by observing how the announcements and withdrawals of these routing beacons propagate throughout the Internet. The geographically dispersed distribution of the RIS Route Collectors makes them ideal for this purpose.

These prefixes can be divided into 2 types:

  • Beacon prefixes: These prefixes are announced and withdrawn according to a set schedule. The propagation of the announcement and withdrawal, or lack thereof, can inform us about the state of the Internet BGP routing system
  • Anchor prefixes: These prefixes are supposed to be announced all the time. Typically, one pair of a beacon and anchor prefix is announced from a specific route collector (RRC). This way anchor prefixes can be used to differentiate between activity seen as a result of changes on the originating RRC and that seen for other reasons. If the anchor flaps, it could mean that the RRC was reloaded and activity of the corresponding beacon can be ignored when doing analysis of the RIS data.

We ask our peers to accept and propagate our anchor and beacon prefixes, and we try to make an effort to have them seen globally, but it must be noted that global visibility of these prefixes is not guaranteed. If you notice any of these prefixes not propagating globally, please let us know at ris@ripe.net

All IPv4 beacon prefixes are announced with additional attributes. We overload the BGP AGGREGATOR attribute to tag each announcement with a timestamp, a sequence number and the identifier of the RRC making the announcement. These are encoded as follows:

  • AGGREGATOR IP ADDRESS: 10.x.y.z, where x, y and z form a 24-bit count of the number of seconds between the start of the month and the time of the announcement.
  • AGGREGATOR AS NUMBER: 64512 + n, where n is a 10-bit number encoded as
MSB                                   LSB
+---+---+---+---+---+---+---+---+---+---+
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
+---+---+---+---+---+---+---+---+---+---+
|    RRC ID     |    Sequence Number    |
+---+---+---+---+---+---+---+---+---+---+

Adding 64512 brings the resulting number into the private AS number range.

If one wants to make special arrangements for routing beacons, contact us at ris@ripe.net, but keep in mind that in IPv4 the address space that we have available is very limited. We will evaluate these requests based on the potential benefit to our community as a whole. An alternative for experiments with routing beacons is the PEERING project (opens new window).

# Current Beaconing Setup

For all beacon prefixes below we have a 2 hour up - 2 hour down schedule. Specifically:

  • Announcements at 00:00, 04:00, 08:00, 12:00, 16:00, 20:00 (UTC)
  • Withdrawals at 02:00, 06:00, 10:00, 14:00, 18:00, 22:00 (UTC)
IPv4 prefix IPv6 prefix type origin RRC (IXP/multihop) peer location(s)
84.205.64.0/24 2001:7FB:FE00::/48 beacon RRC00 (multihop) global
84.205.80.0/24 2001:7FB:FF00::/48 anchor " "
84.205.65.0/24 2001:7FB:FE01::/48 beacon RRC01 (LINX/LONAP) GB
84.205.81.0/24 2001:7FB:FF01::/48 anchor " "
84.205.67.0/24 2001:7FB:FE03::/48 beacon RRC03 (AMS-IX, NL-IX) NL,DK
84.205.83.0/24 2001:7FB:FF03::/48 anchor " "
84.205.68.0/24 2001:7FB:FE04::/48 beacon RRC04 (CIXP) CH,FR
84.205.84.0/24 2001:7FB:FF04::/48 anchor " "
84.205.69.0/24 2001:7FB:FE05::/48 beacon RRC05 (VIX) AT
84.205.85.0/24 2001:7FB:FF05::/48 anchor " "
84.205.70.0/24 2001:7FB:FE06::/48 beacon RRC06 (DIX-IE) JP
84.205.86.0/24 2001:7FB:FF06::/48 anchor " "
84.205.71.0/24 2001:7FB:FE07::/48 beacon RRC07 (NETNOD) SE
84.205.87.0/24 2001:7FB:FF07::/48 anchor " "
84.205.74.0/24 2001:7FB:FE0A::/48 beacon RRC10 (MIX) IT
84.205.90.0/24 2001:7FB:FF0A::/48 anchor " "
84.205.75.0/24 2001:7FB:FE0B::/48 beacon RRC11 (NYIIX) US
84.205.91.0/24 2001:7FB:FF0B::/48 anchor " "
84.205.76.0/24 2001:7FB:FE0C::/48 beacon RRC12 (DE-CIX) DE
84.205.92.0/24 2001:7FB:FF0C::/48 anchor " "
84.205.77.0/24 2001:7FB:FE0D::/48 beacon RRC13 (MSK-IX) RU
84.205.93.0/24 2001:7FB:FF0D::/48 anchor " "
84.205.78.0/24 2001:7FB:FE0E::/48 beacon RRC14 (PAIX) US
84.205.94.0/24 2001:7FB:FF0E::/48 anchor " "
84.205.79.0/24 2001:7FB:FE0F::/48 beacon RRC15 (PTTMetro-SP) BR
84.205.95.0/24 2001:7FB:FF0F::/48 anchor " "
84.205.73.0/24 2001:7FB:FE10::/48 beacon RRC16 (NOTA Miami) US
84.205.89.0/24 2001:7FB:FF10::/48 anchor " "
2001:7FB:FE12::/48 beacon RRC18 (CATNIX) ES
2001:7FB:FF12::/48 anchor " "
84.205.82.0/24 2001:7FB:FE13::/48 beacon RRC19 (NAP Africa JB) ZA
84.205.88.0/24 2001:7FB:FF13::/48 anchor " "
2001:7FB:FE14::/48 beacon RRC20 (SwissIX) CH
2001:7FB:FF14::/48 anchor " "
93.175.149.0/24 2001:7FB:FE15::/48 beacon RRC21 (FranceIX PAR/MAR) FR
93.175.148.0/24 2001:7FB:FF15::/48 anchor " "
2001:7FB:FE16::/48 beacon RRC22 (InterLAN) RO
2001:7FB:FF16::/48 anchor " "
93.175.151.0/24 2001:7FB:FE17::/48 beacon RRC23 (Equinix Singapore) SG
93.175.150.0/24 2001:7FB:FF17::/48 anchor " "
93.175.153.0/24 2001:7FB:FE18::/48 beacon RRC24 (multihop) LACNIC region
93.175.152.0/24 2001:7FB:FF18::/48 anchor " "

# Special beaconing setups

# Anycast failover simulation

The prefix 84.205.72.0/24 is permanent announcement from RRC14 (anchor) and it is periodically announced from RRC03 (beacon) according to this timetable:

  • Announcements at 00:00, 04:00, 08:00, 12:00, 16:00, 20:00 (UTC)
  • Withdrawals at 02:00, 06:00, 10:00, 14:00, 18:00, 22:00 (UTC)

84.205.72.1 is configured as a "pingable address" on both RRCs involved in this setup

IPv4 prefix type origin RRC (IXP/multihop) peer location(s)
84.205.72.0/24 anchor RRC14 (PAIX) US
84.205.72.0/24 beacon RRC03 (AMS-IX,NL-IX) NL,DK

# Resource Certification (RPKI) Routing Beacons

A number of prefixes is permanent announcement from RRC03 to provide insight into the visibility of prefixes in various RPKI states. Each prefix has a pingable address at .1 (IPv4) or ::1 (IPv6).

2001:7fb:fd04::/48 is announced by AS15562 for RPKI TEST (opens new window).

IPv4 prefix IPv6 prefix RPKI state RPKI origin
93.175.146.0/24 2001:7fb:fd02::/48 Valid AS12654
93.175.147.0/24 2001:7fb:fd03::/48 Invalid AS196615
84.205.83.0/24 2001:7fb:ff03::/48 Unknown
2001:7fb:fd04::/48 Invalid AS196615

More information available at RIPE NCC's Resource Certification (RPKI) pages (opens new window), and Routing Certification Beacons on RIPE Labs (opens new window)

# History

We have archived a description of the historical setup of routing beacons here: https://www.ripe.net/analyse/internet-measurements/routing-information-service-ris/historical-list-of-ris-routing-beacons . This description is not entirely accurate and complete, but should serve as a starting point if one wants to study routing beacons pre 20216.

# Machine readable routing beacon info

Current routing beacon information in machine readable format can be found here:

ris-routing-beacons.json

# Further background reading

Some research, presentations and other external documentation on uses of routing beacons can be found here:

# Route Flap Dampening (RFD)

# Ghost routes/zombie routes

# General BGP background

Last Updated: 4/21/2022, 10:15:11 AM