subnet.im

AS203997XTDef Limited

Hong Kong SAR ChinaRegistryRIPE NCCTypeEyeball

As of 10th November 2026, AS203997 (XTDef Limited), an access network registered in Hong Kong SAR China with RIPE NCC, originates 8 IPv4 prefixes covering 2k addresses and 2 IPv6 prefixes. By IPv4 address space that makes it the 25,845th-largest of the 80,723 networks we see originating IPv4, and the 340th-largest of 759 in Hong Kong SAR China. It is seen behind 4 upstream networks, most often AS40994 (Alwyzon (Hohl IT)) and AS20473 (The Constant Company, LLC). Every one of its announcements has 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

8

IPv6 prefixes

2

IPv4 addresses

2k

IPv6 /64s

131k

Upstream graph

The networks AS203997 is seen behind, one and two hops out, drawn from real AS paths.

AS203997Toward the internet core
Upstream graph for AS203997: 11 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS203997XTDef LimitedThis networkAS20473The Constant Comp…AS40994Alwyzon (Hohl IT)AS56662Marcin GondekAS57695Misaka Network, I…AS2914NTT America, Inc.AS1299Arelion (fka. Tel…AS3257GTT Communication…AS13030Init7 (Switzerlan…AS25091IP-Max SAAS917Misaka Network, I…AS60068Datacamp Limited …

Networks observed one and two hops upstream of AS203997 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

8

adjacent networks

Upstreams
450%
Peers
450%
Downstreams
00%

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

Upstreams of AS203997
NetworkCountryRelationshipPathsVantage pts
AS40994Alwyzon (Hohl IT)ATPeer361136
AS20473The Constant Company, LLCUSPeer286136
AS57695Misaka Network, Inc.USPeer7676
AS56662Marcin GondekPLPeer11

Prefixes

The largest blocks AS203997 originates, widest first.

Largest prefixes originated by AS203997
PrefixAddressesVisibility
81.18.60.0/2425675/76
89.23.94.0/2425675/76
141.11.60.0/2425675/76
151.244.252.0/2425675/76
164.138.4.0/2425676/76
178.95.202.0/2425675/76
179.61.243.0/2425676/76
191.44.74.0/2425675/76
2a10:e8c0:43::/4865.5k × /6461/63
2a10:e8c0:358::/4865.5k × /6461/63

Routing health

How AS203997'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

  • Valid100.0%10
  • Invalid0.0%0
  • No ROA0.0%0

Propagation

  • Globally propagated90% of full-feed peers or more100.0%10
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 8 prefixes

IPv6 — 2 prefixes

  • /4865.5k × /64100.0%2

Recent changes

Announcements that started or stopped since 11th Oct 2026.

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