Autonomous System
AS2852 · CESNET z.s.p.o.
Overview
AS2852 is announced on the Internet: RIPE RIS route collectors currently see 26 IPv4 prefixes and 1 IPv6 prefix originated by this network. Together, its IPv4 prefixes cover 849,920 addresses, with overlapping prefixes counted once. In the paths the collectors record, it has 76 upstream neighbours (transit providers or peers) and 29 downstream neighbours (customers or networks it carries). Its most visible upstreams are Hurricane Electric LLC (AS6939), GEANT Vereniging (AS21320), and Cogent Communications, LLC (AS174). AS2852 was assigned by RIPE NCC, and its registration country is Czechia.
Source: RIPEstat (RIPE NCC), RIS route collectors. Read on October 16, 2026 at 8:57 PM UTC. This page is refreshed at most every 12 hours.
Go further
The trace goes to 146.102.0.1, the first address of 146.102.0.0/16. 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 (26 prefixes)
| Prefix | Addresses |
|---|---|
| 78.128.128.0/17 | 32,768 |
| 146.102.0.0/16 | 65,536 |
| 147.32.0.0/16 | 65,536 |
| 147.33.0.0/16 | 65,536 |
| 147.228.0.0/16 | 65,536 |
| 147.230.0.0/16 | 65,536 |
| 147.231.0.0/16 | 65,536 |
| 147.251.0.0/16 | 65,536 |
| 158.194.0.0/16 | 65,536 |
| 158.196.0.0/16 | 65,536 |
| 160.216.0.0/16 | 65,536 |
| 160.217.0.0/16 | 65,536 |
| 185.8.160.0/22 | 1,024 |
| 193.84.32.0/20 | 4,096 |
| 193.84.53.0/24 | 256 |
| 193.84.55.0/24 | 256 |
| 193.84.56.0/21 | 2,048 |
| 193.84.80.0/22 | 1,024 |
| 193.84.104.0/22 | 1,024 |
| 193.84.116.0/23 | 512 |
| 193.84.160.0/20 | 4,096 |
| 193.84.192.0/19 | 8,192 |
| 193.84.192.0/20 | 4,096 |
| 193.84.208.0/20 | 4,096 |
| 195.113.0.0/16 | 65,536 |
| 195.178.64.0/19 | 8,192 |
IPv6 prefixes (1 prefix)
| Prefix |
|---|
| 2001:718::/29 |
Neighbours
Upstreams (transit or peers) (76)
| AS | Network | Visibility |
|---|---|---|
| AS6939 | Hurricane Electric LLC | 2,763 |
| AS21320 | GEANT Vereniging | 963 |
| AS174 | Cogent Communications, LLC | 585 |
| AS1853 | ACOnet - ACONET | 536 |
| AS60606 | Blindspot PRO-ZETA a.s. | 466 |
| AS6461 | Zayo Bandwidth | 156 |
| AS20965 | GEANT Vereniging | 126 |
| AS8218 | Zayo Infrastructure France SA | 60 |
| AS20723 | AVONET, s.r.o. | 60 |
| AS35280 | F5 Networks SARL | 54 |
| AS34549 | meerfarbig GmbH & Co. KG | 53 |
| AS5405 | Inter.link GmbH | 45 |
| AS14840 | BR.Digital Telecom | 41 |
| AS34927 | iFog GmbH | 40 |
| AS8298 | IPng Networks GmbH | 38 |
| AS25091 | IP-Max SA | 37 |
| AS4455 | IX Reach Ltd | 34 |
| AS34177 | - | 34 |
| AS35625 | Eurofiber France SAS | 34 |
| AS4230 | CLARO S.A. | 33 |
| AS20764 | CJSC RASCOM | 33 |
| AS41327 | Fiber Telecom S.p.A. | 33 |
| AS24961 | WIIT AG | 31 |
| AS29691 | Nine Internet Solutions AG | 31 |
| AS20485 | Joint Stock Company TransTeleCom | 30 |
| AS22356 | Durand do Brasil Ltda | 25 |
| AS37468 | Angola Cables | 25 |
| AS29632 | Netassist International EOOD | 23 |
| AS37100 | SEACOM Limited | 22 |
| AS39351 | 31173 Services AB | 22 |
The 30 most visible of 76.
Downstreams (customers) (29)
| AS | Network | Visibility |
|---|---|---|
| AS61110 | Sprava informacnich technologii mesta Plzne, p.o. | 515 |
| AS48091 | Kraj Vysocina | 506 |
| AS199711 | National Cyber and Information Security Agency | 504 |
| AS201648 | Plzensky kraj | 494 |
| AS210498 | Kraj Vysocina | 494 |
| AS202874 | Zlinsky Kraj | 491 |
| AS197451 | Brno University of Technology | 484 |
| AS200874 | Liberecky kraj | 480 |
| AS212876 | Pardubicky Kraj | 479 |
| AS197277 | State Institute for Drug Control | 478 |
| AS210367 | - | 400 |
| AS213152 | - | 395 |
| AS208093 | - | 319 |
| AS204772 | - | 310 |
| AS51727 | - | 268 |
| AS198500 | - | 174 |
| AS702 | Verizon Business | 116 |
| AS199604 | - | 104 |
| AS1853 | ACOnet - ACONET | 78 |
| AS6855 | - | 63 |
| AS16019 | Vodafone Czech Republic a.s. | 48 |
| AS2607 | Zdruzenie pouzivatelov Slovenskej akademickej datovej siete SANET | 37 |
| AS2686 | - | 2 |
| AS5610 | - | 1 |
| AS6461 | Zayo Bandwidth | 1 |
| AS16509 | Amazon.com, Inc. | 1 |
| AS34080 | - | 1 |
| AS42000 | - | 1 |
| AS203165 | - | 1 |
72 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.