subnet.im

AS397373H4Y Technologies LLC

United StatesRegistryARINTypeContent

As of 26th September 2026, AS397373 (H4Y Technologies LLC), a content network registered in the United States with ARIN, originates 207 IPv4 prefixes covering 62.7k addresses and 13 IPv6 prefixes. By IPv4 address space that makes it the 4,054th-largest of the 79,516 networks we see originating IPv4, and the 1,472nd-largest of 18,424 in the United States. It is seen behind 9 upstream networks, most often AS6939 (Hurricane Electric LLC) and AS3356 (Lumen (Level 3)), and in front of 10 downstream networks. 86% of its announcements have a valid RPKI ROA, and none are RPKI-invalid. Over 99% of its routes reach at least 90% of full-feed peers, and 1 prefix is also originated by another network.

At a glance

IPv4 prefixes

207

IPv6 prefixes

13

IPv4 addresses

62.7k

IPv6 /64s

1.2M

Upstream graph

The networks AS397373 is seen behind, one and two hops out, drawn from real AS paths.

AS397373Toward the internet core
Upstream graph for AS397373: 12 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS397373H4Y Technologies …This networkAS174Cogent Communicat…AS3356Lumen (Level 3)AS6461Zayo BandwidthAS6939Hurricane Electri…AS40676Psychz NetworksAS1299Arelion (fka. Tel…AS151326DCConnect Communi…AS3549Lumen (fka. Globa…AS32590Valve CorporationAS2914NTT America, Inc.AS18106Viewqwest Pte LtdAS20130Depaul University

Networks observed one and two hops upstream of AS397373 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

38

adjacent networks

Upstreams
924%
Peers
1950%
Downstreams
1026%

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

Upstreams of AS397373
NetworkCountryRelationshipPathsVantage pts
AS6939Hurricane Electric LLCUSPeer6,843102
AS3356Lumen (Level 3)USPeer6,434144
AS6461Zayo BandwidthUSPeer2,83543
AS174Cogent Communications, LLCUSPeer2,47491
AS40676Psychz NetworksUSPeer948145
AS53340FiberHub (VegasNAP)USPeer873144
AS14935Monticello Networks, Inc.USPeer14917
AS11426Charter Communications IncUSPeer263
AS17216DC74 LLCUSPeer83

Prefixes

All 220

The largest blocks AS397373 originates, widest first.

Largest prefixes originated by AS397373
PrefixAddressesVisibility
5.182.120.0/221k81/81
45.191.164.0/221k81/81
104.249.56.0/221k81/81
155.254.20.0/221k81/81
155.254.24.0/221k81/81
176.53.164.0/221k81/81
199.83.208.0/221k81/81
199.83.212.0/221k81/81
2.56.114.0/2351281/81
5.182.118.0/2351281/81

Routing health

How AS397373'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

  • Valid85.9%189
  • Invalid0.0%0
  • No ROA14.1%31

Propagation

  • Globally propagated90% of full-feed peers or more99.5%219
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.5%1

Prefix sizes

IPv4 — 207 prefixes

IPv6 — 13 prefixes

  • /46262k × /6415.4%2
  • /4865.5k × /6484.6%11

Recent changes

Announcements that started or stopped since 28th Aug 2026.

22 announced and 2 withdrawn in all; the most recent are shown.

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