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AS21687Zayo Bandwidth

United StatesRegistryARIN

As of 11th November 2026, AS21687 (Zayo Bandwidth), a network registered in the United States with ARIN, originates 2 IPv6 prefixes. It is seen behind 1 upstream network, most often AS46887 (Zayo (fka. Crown Castle)). None of its announcements have a valid RPKI ROA. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

0

IPv6 prefixes

2

IPv4 addresses

0

IPv6 /64s

67.1M

Upstream graph

The networks AS21687 is seen behind, one and two hops out, drawn from real AS paths.

AS21687Toward the internet core
Upstream graph for AS21687: 3 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS21687Zayo BandwidthThis networkAS46887Zayo (fka. Crown …AS6461Zayo BandwidthAS47065USC / UFMG PEERIN…

Networks observed one and two hops upstream of AS21687 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

2

adjacent networks

Upstreams
150%
Peers
150%
Downstreams
00%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS21687
NetworkCountryRelationshipPathsVantage pts
AS46887Zayo (fka. Crown Castle)USPeer12462

Prefixes

The largest blocks AS21687 originates, widest first.

Largest prefixes originated by AS21687
PrefixAddressesVisibility
2607:f7a8::/3933.6M × /6462/63
2607:f7a8:1200::/3933.6M × /6462/63

Routing health

How AS21687's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid0.0%0
  • Invalid0.0%0
  • No ROA100.0%2

Propagation

  • Globally propagated90% of full-feed peers or more100.0%2
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv6 — 2 prefixes

  • /3933.6M × /64100.0%2

Recent changes

Announcements that started or stopped since 12th Oct 2026.

No announcement by AS21687 started or stopped in this period.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.