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AS13977Fidium

United StatesRegistryARINTypeEyeball

As of 23rd October 2026, AS13977 (Fidium), an access network registered in the United States with ARIN, originates 776 IPv4 prefixes covering 857k addresses and 8 IPv6 prefixes. By IPv4 address space that makes it the 513th-largest of the 79,652 networks we see originating IPv4, and the 120th-largest of 18,475 in the United States. It is seen behind 4 upstream networks, most often AS6461 (Zayo Bandwidth) and AS174 (Cogent Communications, LLC), and in front of 51 downstream networks. Under 1% of its announcements have a valid RPKI ROA, and none are RPKI-invalid. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

776

IPv6 prefixes

8

IPv4 addresses

857k

IPv6 /64s

5B

Upstream graph

The networks AS13977 is seen behind, one and two hops out, drawn from real AS paths.

AS13977Toward the internet core
Upstream graph for AS13977: 11 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS13977FidiumThis networkAS174Cogent Communicat…AS6461Zayo BandwidthAS33422New England Teleh…AS63243SynergentAS1299Arelion (fka. Tel…AS151326DCConnect Communi…AS2914NTT America, Inc.AS32590Valve CorporationAS13536FirstLight Networ…AS11351Charter Communica…AS32787Akamai (Prolexic)

Networks observed one and two hops upstream of AS13977 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

109

adjacent networks

Upstreams
44%
Peers
5450%
Downstreams
5147%

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

Upstreams of AS13977
NetworkCountryRelationshipPathsVantage pts
AS6461Zayo BandwidthUSPeer41,832140
AS174Cogent Communications, LLCUSPeer28,188134
AS63243SynergentUSPeer3535
AS33422New England Telehealth ConsortiumUSPeer3129

Prefixes

All 784

The largest blocks AS13977 originates, widest first.

Largest prefixes originated by AS13977
PrefixAddressesVisibility
70.8.0.0/1665.5k76/77
163.252.0.0/1665.5k76/77
69.53.0.0/1732.8k76/77
163.252.0.0/1732.8k76/77
216.212.0.0/1732.8k76/77
64.222.128.0/1816.4k76/77
64.222.192.0/1816.4k76/77
70.8.128.0/1816.4k76/77
163.252.192.0/1816.4k76/77
216.212.0.0/1816.4k76/77

Routing health

How AS13977'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

  • Valid0.6%5
  • Invalid0.0%0
  • No ROA99.4%779

Propagation

  • Globally propagated90% of full-feed peers or more100.0%784
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 776 prefixes

IPv6 — 8 prefixes

  • /324.3B × /6412.5%1
  • /36268M × /6425.0%2
  • /3867.1M × /6425.0%2
  • /4865.5k × /6437.5%3

Recent changes

Announcements that started or stopped since 23rd Sept 2026.

16 announced and 20 withdrawn in all; the most recent are shown.

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