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AS47720Cork Internet Exchange Limited

IrelandRegistryRIPE NCC

As of 10th November 2026, AS47720 (Cork Internet Exchange Limited), a network registered in Ireland with RIPE NCC, originates 14 IPv4 prefixes covering 20k addresses and 3 IPv6 prefixes. By IPv4 address space that makes it the 7,203rd-largest of the 80,733 networks we see originating IPv4, and the 21st-largest of 197 in Ireland. It is seen behind 30 upstream networks, most often AS8220 (COLT) and AS1273 (Vodafone Group PLC), and in front of 8 downstream networks. 6% of its announcements have a valid RPKI ROA; 1 is RPKI-invalid. 94% 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

14

IPv6 prefixes

3

IPv4 addresses

20k

IPv6 /64s

8.6B

Upstream graph

The networks AS47720 is seen behind, one and two hops out, drawn from real AS paths.

AS47720Toward the internet core
Upstream graph for AS47720: 12 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS47720Cork Internet Exc…This networkAS1273Vodafone Group PLCAS3257GTT Communication…AS6939Hurricane Electri…AS8220COLTAS25091IP-Max SAAS41811CONVERGENCE (GROU…AS6667Elisa OyjAS398465Rackdog LLCAS20130Depaul UniversityAS132337AxclusiveAS1299Arelion (fka. Tel…AS3356Lumen (Level 3)

Networks observed one and two hops upstream of AS47720 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

144

adjacent networks

Upstreams
3021%
Peers
10674%
Downstreams
86%

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

Upstreams of AS47720
NetworkCountryRelationshipPathsVantage pts
AS8220COLTGBPeer85348
AS1273Vodafone Group PLCEUPeer49762
AS3257GTT Communications Inc.USPeer37998
AS6939Hurricane Electric LLCUSPeer29863
AS25091IP-Max SACHPeer493
AS58511Swoop (Anycast Global Backbone)AUPeer282
AS52075Wifirst S.A.S.FRPeer282
AS39122Blacknight Internet Solutions LimitedIEPeer272
AS49544i3D.net B.VNLPeer262
AS3170VeloxServ Communications LtdGBPeer262

Prefixes

The largest blocks AS47720 originates, widest first.

Largest prefixes originated by AS47720
PrefixAddressesVisibility
217.74.48.0/204.1k76/76
84.39.232.0/212k76/76
89.31.168.0/212k76/76
91.103.0.0/212k76/76
217.74.56.0/212k76/76
185.49.60.0/221k76/76
185.57.116.0/221k76/76
185.137.20.0/221k76/76
185.175.168.0/221k76/76
185.176.0.0/221k76/76

Routing health

How AS47720'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

  • Valid5.9%1
  • Invalid5.9%1
  • No ROA88.2%15

Propagation

  • Globally propagated90% of full-feed peers or more94.1%16
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%5.9%1

Prefix sizes

IPv4 — 14 prefixes

IPv6 — 3 prefixes

  • /324.3B × /6466.7%2
  • /4865.5k × /6433.3%1

Recent changes

Announcements that started or stopped since 11th Oct 2026.

  • Announced45.140.144.0/249th Nov 2026
  • Announced217.74.48.0/2029th Oct 2026
  • Withdrawn217.74.48.0/2028th Oct 2026
  • Withdrawn45.140.144.0/2412th Oct 2026

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