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Autonomous System

AS47720 ยท Cork Internet Exchange Limited

Overview

AS47720 is announced on the Internet: RIPE RIS route collectors currently see 13 IPv4 prefixes and 3 IPv6 prefixes originated by this network. Together, its IPv4 prefixes cover 15,616 addresses, with overlapping prefixes counted once. In the paths the collectors record, it has 36 upstream neighbours (transit providers or peers) and 7 downstream neighbours (customers or networks it carries). Its most visible upstreams are COLT Technology Services Group Limited (AS8220), Hurricane Electric LLC (AS6939), and GTT Communications Inc. (AS3257). AS47720 was assigned by RIPE NCC, and its registration country is Ireland.

Source: RIPEstat (RIPE NCC), RIS route collectors. Read on October 16, 2026 at 8:58 PM UTC. This page is refreshed at most every 12 hours.

Go further

The trace goes to 217.74.48.1, the first address of 217.74.48.0/20. An address picked inside a prefix may not answer (nothing listens there, or the network filters probes): the trace then shows the path up to the last network that replies.

Announced prefixes

IPv4 prefixes (13 prefixes)

PrefixAddresses
84.39.232.0/212,048
89.31.168.0/212,048
91.103.0.0/212,048
91.223.9.0/24256
185.49.60.0/221,024
185.57.116.0/221,024
185.137.20.0/221,024
185.175.168.0/221,024
185.176.0.0/221,024
217.74.48.0/204,096
217.74.48.0/221,024
217.74.52.0/221,024
217.74.56.0/212,048

IPv6 prefixes (3 prefixes)

Prefix
2607:6b80:3d::/48
2a02:2078::/32
2a02:5b20::/32

Neighbours

Upstreams (transit or peers) (36)

ASNetworkVisibility
AS8220COLT Technology Services Group Limited792
AS6939Hurricane Electric LLC779
AS3257GTT Communications Inc.542
AS1273IDDQD-AS440
AS25091IP-Max SA47
AS34549meerfarbig GmbH & Co. KG36
AS50304Blix Solutions AS23
AS34927iFog GmbH20
AS5405Inter.link GmbH19
AS9002RETN Limited18
AS14840BR.Digital Telecom16
AS29075IELO-LIAZO SERVICES SAS16
AS34177-16
AS35280F5 Networks SARL16
AS37497Network Platforms (PTY) LTD16
AS12779-15
AS41327Fiber Telecom S.p.A.14
AS48362Stadtwerke Feldkirch14
AS3214xTom GmbH12
AS56911Warian S.R.L.12
AS286GTT Communications Inc.8
AS3741Dimension Data8
AS37468Angola Cables8
AS55850Mercury NZ Limited8
AS6797-7
AS7195EDGEUNO S.A.S7
AS15958CETIN Ltd. Belgrade7
AS31500Global Network Management Inc7
AS37100SEACOM Limited7
AS4455IX Reach Ltd6

The 30 most visible of 36.

Downstreams (customers) (7)

ASNetworkVisibility
AS42953Internet Neutral Exchange Association Company Limited By Guarantee478
AS15405East Cork Broadband Limited469
AS205967Sleepless Server Solutions Ltd.465
AS47680EOBO Ltd T/A BBnet286
AS201902Bicom Systems Limited266
AS196737Airwave Internet265
AS44358Kauno Technologijos Universitetas171

34 more neighbours appear on both sides of this network depending on the path, so they are counted in neither list.

Visibility is RIPEstat's count of how often the route collectors observed the link. It compares neighbours with each other; it is not a traffic volume.

How to read this page

An Autonomous System (AS) is a network run under one routing policy: an internet provider, a cloud, a content network, a university. Each one has a number, its ASN, assigned by a regional registry (ARIN, RIPE NCC, APNIC, LACNIC, AFRINIC), and uses BGP, the protocol networks use to tell each other where addresses are, to announce the blocks of addresses it delivers to.

A prefix such as 203.0.113.0/24 is a block of addresses: the number after the slash says how many bits are fixed, so a /24 holds 256 IPv4 addresses and a /16 holds 65,536. Networks often announce a large block and smaller pieces of it at the same time, which is why the address total counts each address once.

Neighbours come from the paths themselves. A network that appears just before this one in a path, on the collector's side, is an upstream: a transit provider or a peer. One that appears just after it is a downstream, usually a customer. Peering at an internet exchange also shows up as an upstream, so the upstream list is not a list of paid transit.

The data comes from RIPEstat, run by the RIPE NCC, which gathers the routing tables of hundreds of networks through its RIS route collectors. This page reads it when it is visited and keeps it for 12 hours at most; the BGP viewer reads it live.

Frequently asked questions

How do I find the ASN of an IP address?
Type the address in the BGP viewer: it shows the prefix that covers it, the AS that originates that prefix and the paths seen towards it. A traceroute also names the network of each hop, so you can see every AS a connection crosses.
Why does one company have several ASNs?
Large operators split their network by region, by activity or by history: a cloud may use one number for its backbone and another for a region, and every acquisition brings its own numbers. Each number has its own page, with its own prefixes and neighbours.
Why do prefix counts differ from one site to another?
Each source sees the routing table from different collectors, at a different time, and counts differently: some include prefixes withdrawn in recent weeks, some merge a block and its pieces. This page counts the prefixes RIPE RIS collectors see originated by the network at the end of the latest two-week window, and counts each IPv4 address once.
Is this the list of IP ranges of a cloud provider?
It is what its networks announce, which is what the Internet routes to them. Many providers also publish an official list of ranges per service and region; that list is the reference for firewall rules, because a range can be announced before it is used, or announced by another of their AS numbers.