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AS43037

Seznam.cz, a.s.

RIPE NCC CZ active Announced
More ASNs in Czechia →
Organization
Seznam.cz, a.s.
SEZNAM-CZ
Registered
May 29, 2007
19 years ago
IPv4 Prefixes
6
3,072 addresses
IPv6 Prefixes
6
65,536 × /48
BGP Neighbours
114
52 upstream/peer · 1 downstream · 62 collector-only

Registration

AS Number AS43037 AS Name SEZNAM-CZ Organization Seznam.cz, a.s. Organization ID ORG-Sa508-RIPE Address Radlicka 3294/10, 15000, Prague 5, CZECH REPUBLIC Country Czechia (CZ) Registry RIPE NCC Allocated May 29, 2007 Record Created May 29, 2007 Last Updated Nov 15, 2017 Status
active
WHOIS Server whois.ripe.net AS Description SEZNAM-CZ - SEZNAM-CZ, CZ Abuse Email [email protected]

IPv4 Prefixes

6 prefixes · 3,072 addresses Routing data as of 2026-10-05 16:00 UTC

PrefixRangeAddresses
77.75.72.0/2377.75.72.0 – 77.75.73.255512
77.75.74.0/2477.75.74.0 – 77.75.74.255256
77.75.75.0/2477.75.75.0 – 77.75.75.255256
77.75.76.0/2377.75.76.0 – 77.75.77.255512
77.75.78.0/2377.75.78.0 – 77.75.79.255512
185.66.188.0/22185.66.188.0 – 185.66.191.2551,024

IPv6 Prefixes

6 prefixes · 65,536 × /48 · 1 top-level Routing data as of 2026-10-05 16:00 UTC

PrefixAddresses
2a02:598::/32296
2a02:598:2::/48280
2a02:598:a::/48280
2a02:598:b::/48280
2a02:598:3333::/48280
2a02:598:4444::/48280

BGP Neighbours

114 unique neighbours · 52 upstream/peer · 1 downstream · 62 collector-only. A neighbour can be seen on more than one side. Rows are ordered by AS paths: the number of BGP paths seen by RIPE RIS that contain the adjacency. Sightings count each IPv4/IPv6 route with the adjacency once per RIS peer that sees it (routes × peers), so they show how widely it is seen, not how many distinct routes it carries.

Upstream & peer side (52)

Networks seen to the left of this AS in BGP paths, toward the route collectors — typically its transit providers (upstreams) and peers.

ASNameAS pathsIPv4 sightingsIPv6 sightings
AS5610O2-CZECH-REPUBLIC O2 Czech Republic, a.s.213642457
AS6939HURRICANE - Hurricane Electric LLC12197508
AS29208QUANTCOM-AS Quantcom, a.s.110413285
AS35280F5 F5 Networks SARL103528
AS5405INTERDOTLINK Inter.link GmbH93515
AS34549MEER-AS meerfarbig GmbH & Co. KG72713
AS4230AS4230 - CLARO S.A.62114
AS20562OPEN-PEERING-AS Broadband Hosting B.V.61614
AS25091IP-Max IP-Max SA63521
AS29632NASSIST-AS Netassist International EOOD6020
AS34019HIVANE Hivane Association63535
AS35625EUROFIBER-FRANCE Eurofiber France SAS62121
AS6057AS6057 - Administracion Nacional de Telecomunicaciones41414
AS7195AS7195 - EDGEUNO S.A.S477
AS8298IPNG IPng Networks GmbH4714
AS8758IWAY Iway AG42121
AS12779ITGATE IT.Gate S.p.A.43528
AS12859NL-BIT BIT BV41420
AS14840AS14840 - BR.Digital Telecom43535
AS20485TRANSTELECOM Joint Stock Company TransTeleCom4147
AS20764RASCOM-AS CJSC RASCOM41414
AS24961MYLOC-AS WIIT AG41414
AS29691NINE Nine Internet Solutions AG41414
AS34177CELESTE-AS Celeste SAS4147
AS34927iFog-GmbH iFog GmbH41414
AS37468Angola Cables - Angola Cables4147
AS39351ESAB-AS 31173 Services AB41414
AS41327FIBERTELECOM-AS Fiber Telecom S.p.A.4147
AS47147AS-ANX Anexia Cloud Solutions GmbH42814
AS48362TKSWF-AS Stadtwerke Feldkirch42828
AS33891CORE-BACKBONE Core-Backbone GmbH303
AS1764NEXTLAYER-AS Next Layer Telekommunikationsdienstleistungs- und Beratungs GmbH277
AS1836GREEN green.ch AG2147
AS4455BSO IX Reach Ltd277
AS6204ZET-NET TMRC GROUP SRL270
AS6663TTI-NET Euroweb Romania S.R.L.276
AS6695DECIX-AS DE-CIX Management GmbH277
AS6797GLOBALCONNECT-NET GlobalConnect AB21414
AS7713telkomnet-as-ap - PT Telekomunikasi Indonesia270
AS20326TERASWITCH - TeraSwitch Networks Inc.276
AS22356AS22356 - Durand do Brasil Ltda277
AS24889MONZOON-AS Monzoon Networks AG207
AS28716RETELIT-AS Retelit Digital Services S.p.A.277
AS37100SEACOM Limited - SEACOM Limited270
AS39249KICUA-AS Netassist International EOOD207
AS47232ISPAlliance ISP Alliance a.s.270
AS60171AFRIX-AS AFR-IX TELECOM S.A.276
AS137409GSLNETWORKS-AS-AP - GSL Networks Pty LTD277
AS205103TELEGRAPH-AS Telegraph42 Management GmbH277
AS212024RISSON Marc Schmitt277
AS264409AS264409 - Huge Solucoes Corporativas Ltda220
AS12577MMC-AT-AS MMC GmbH101

Downstream side (1)

Networks seen to the right of this AS in BGP paths — networks whose routes it carries, typically its customers (downstreams).

ASNameAS pathsIPv4 sightingsIPv6 sightings
AS200600SEZNAM-CZ-DC Seznam.cz datova centra, s.r.o.349339336

Collector-only (62)

Networks seen to the left of this AS only when they peer directly with a RIPE RIS route collector, so the adjacency may be an artefact of that peering; many of them also appear on the downstream side.

ASNameAS pathsIPv4 sightingsIPv6 sightings
AS553BELWUE Universitaet Stuttgart277
AS559Switch SWITCH277
AS1828UNITAS - Unitas Global207
AS3212TELEMACH Telemach Slovenija d.o.o.277
AS3214XTOM xTom GmbH2147
AS6424EDGOO EDGOO NETWORKS UNIPESSOAL LDA277
AS6881NIXCZ NIX.CZ z.s.p.o.277
AS8218NEO-ASN Zayo Infrastructure France SA24949
AS8529OMANTEL-AS Zain Omantel International FZ-LLC21414
AS8888XTOM xTom Pty Ltd277
AS13237LAMBDANET-AS euNetworks GmbH270
AS14630INVESCO - Invesco Group Services, Inc.270
AS15547NETPLUS netplus.ch SA2143
AS17639CONVERGE-AS - Converge ICT Solutions Inc.217
AS18106VIEWQWEST-SG-AP - Viewqwest Pte Ltd270
AS20932SIG-ST Services Industriels de Geneve277
AS21412CGATES-AS UAB "Cgates"270
AS24482SGGS-AS-AP - SG.GS27777
AS25160VORBOSS Vorboss Limited21414
AS25220GLOBALNOC-AS equada network GmbH277
AS28917Fiord-AS Fiord Networks, UAB2014
AS29075IELO IELO-LIAZO SERVICES SAS277
AS29140HOSTSERVER-AS Hostserver GmbH277
AS29504LBCFREE Freenet Liberec, z.s.277
AS31510IKB-AS Innsbrucker Kommunalbetriebe AG277
AS34288AS34288 Kantonsschule Zug277
AS35360GARGUNET Frederic Gargula277
AS35598INETCOM INETCOM CARRIER LLC270
AS35710WEBERCLOUD weber.digital GmbH2140
AS36236NETACTUATE - NetActuate, Inc277
AS37721Virtual Technologies & Solutions - Virtual Technologies & Solutions272
AS40994Alwyzon Hohl IT e.U.277
AS42541FIBERBY Fiberby ApS277
AS44901belcloud Belcloud LTD277
AS45489SLT-GLOBAL - Sri Lanka Telecom PLC, GLobal Peering277
AS47692NESSUS Nessus GmbH21414
AS48919UA-CITY-AS UACITY Ltd.277
AS49544i3Dnet i3D.net B.V21414
AS51184FONIRA Fonira Telekom GmbH21414
AS51185MAINSTREAMING-AS MainStreaming SpA207
AS56662EUTPNET Marcin Gondek207
AS56987AS-ABACLOUDA ABACLOUDA SAS277
AS57777MASSAR Jeroen Massar277
AS58057SECUREBIT Securebit AG277
AS58299OPENFACTORY-AS Openfactory GmbH277
AS61573AS61573 - IP TELECOM277
AS64475FREIFUNK-FRANKFURT Freifunk Frankfurt am Main e.V.277
AS142271DOUBLESQUARE-AS-AP - EWS DS Networks Inc270
AS198150SIACOM-AS SIACOM JSC277
AS198249OPSONE Ops One AG207
AS198385AlpineDC AlpineDC SA277
AS199524GCORE G-Core Labs S.A.277
AS199938NETZWERGE Netzwerge GmbH277
AS205112PHILUNET PHILUNET GmbH270
AS206356Freifunk-Essen Freifunk Essen e.V.270
AS209823ENKI-AS Enki Multimedia EURL207
AS210937Showfom Xiufeng Guo277
AS212483level86 LEVEL EIGHTY-SIX COMMUNICATIONS LTD21414
AS213151CHRISELSEN Christian Elsen277
AS213241TECHIT TECHIT.BE SRL207
AS264479AS264479 - Turbozone Internet271
AS200600SEZNAM-CZ-DC Seznam.cz datova centra, s.r.o.111

Raw RDAP Response

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  "handle": "AS43037",
  "startAutnum": 43037,
  "endAutnum": 43037,
  "name": "SEZNAM-CZ",
  "status": [
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          ],
          [
            "kind",
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            "org"
          ],
          [
            "adr",
            {
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            },
            "text",
            [
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            ]
          ],
          [
            "tel",
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            "text",
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          ],
          [
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              "type": "fax"
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            "text",
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        ]
      ],
      "roles": [
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      "links": [
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          "href": "https://rdap.db.ripe.net/entity/ORG-Sa508-RIPE"
        },
        {
          "value": "http://www.ripe.net/data-tools/support/documentation/terms",
          "rel": "copyright",
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    {
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        },
        {
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          "href": "https://rdap.db.ripe.net/entity/SEZNAM-MNT"
        },
        {
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          [
            "kind",
            {},
            "text",
            "group"
          ],
          [
            "adr",
            {
              "label": "Radlicka 3294/10 150 00 Prague 5 Czech Republic"
            },
            "text",
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              "",
              "",
              "",
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            ]
          ],
          [
            "tel",
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              "type": "voice"
            },
            "text",
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          ],
          [
            "email",
            {
              "type": "abuse"
            },
            "text",
            "[email protected]"
          ]
        ]
      ],
      "roles": [
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      "links": [
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        },
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      ],
      "objectClassName": "entity"
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          [
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            ]
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      ],
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              ],
              [
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                "REDACTED"
              ],
              [
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                {},
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              ]
            ]
          ],
          "roles": [
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          ],
          "links": [
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              "rel": "self",
              "href": "https://rdap.db.ripe.net/entity/SEZNAM-MNT"
            },
            {
              "value": "http://www.ripe.net/data-tools/support/documentation/terms",
              "rel": "copyright",
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            }
          ],
          "objectClassName": "entity"
        }
      ],
      "objectClassName": "entity"
    }
  ],
  "links": [
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      "value": "https://rdap.db.ripe.net/autnum/43037",
      "rel": "rdap-up",
      "href": "https://rdap.db.ripe.net/autnums/rirSearch1/rdap-up/AS43037",
      "type": "application/rdap+json"
    },
    {
      "value": "https://rdap.db.ripe.net/autnum/43037",
      "rel": "rdap-up rdap-active",
      "href": "https://rdap.db.ripe.net/autnums/rirSearch1/rdap-up/AS43037?status=active",
      "type": "application/rdap+json"
    },
    {
      "value": "https://rdap.db.ripe.net/autnum/43037",
      "rel": "rdap-down",
      "href": "https://rdap.db.ripe.net/autnums/rirSearch1/rdap-down/AS43037",
      "type": "application/rdap+json"
    },
    {
      "value": "https://rdap.db.ripe.net/autnum/43037",
      "rel": "rdap-top",
      "href": "https://rdap.db.ripe.net/autnums/rirSearch1/rdap-top/AS43037",
      "type": "application/rdap+json"
    },
    {
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      "href": "https://rdap.db.ripe.net/autnums/rirSearch1/rdap-top/AS43037?status=active",
      "type": "application/rdap+json"
    },
    {
      "value": "https://rdap.db.ripe.net/autnum/43037",
      "rel": "rdap-bottom",
      "href": "https://rdap.db.ripe.net/autnums/rirSearch1/rdap-bottom/AS43037",
      "type": "application/rdap+json"
    },
    {
      "value": "https://rdap.db.ripe.net/autnum/43037",
      "rel": "self",
      "href": "https://rdap.db.ripe.net/autnum/43037",
      "type": "application/rdap+json"
    },
    {
      "value": "http://www.ripe.net/data-tools/support/documentation/terms",
      "rel": "copyright",
      "href": "http://www.ripe.net/data-tools/support/documentation/terms"
    }
  ],
  "events": [
    {
      "eventAction": "registration",
      "eventDate": "2007-05-29T08:00:03Z"
    },
    {
      "eventAction": "last changed",
      "eventDate": "2017-11-15T09:48:45Z"
    }
  ],
  "rdapConformance": [
    "nro_rdap_profile_asn_flat_0",
    "rirSearch1",
    "autnums",
    "cidr0",
    "rdap_level_0",
    "nro_rdap_profile_0",
    "redacted"
  ],
  "notices": [
    {
      "title": "Filtered",
      "description": [
        "This output has been filtered."
      ]
    },
    {
      "title": "Whois Inaccuracy Reporting",
      "description": [
        "If you see inaccuracies in the results, please visit:"
      ],
      "links": [
        {
          "value": "https://rdap.db.ripe.net/autnum/43037",
          "rel": "inaccuracy-report",
          "href": "https://www.ripe.net/contact-form?topic=ripe_dbm&show_form=true",
          "type": "text/html"
        }
      ]
    },
    {
      "title": "Source",
      "description": [
        "Objects returned came from source",
        "RIPE"
      ]
    },
    {
      "title": "Terms and Conditions",
      "description": [
        "This is the RIPE Database query service. The objects are in RDAP format."
      ],
      "links": [
        {
          "value": "https://rdap.db.ripe.net/autnum/43037",
          "rel": "terms-of-service",
          "href": "http://www.ripe.net/db/support/db-terms-conditions.pdf",
          "type": "application/pdf"
        }
      ]
    }
  ],
  "port43": "whois.ripe.net",
  "objectClassName": "autnum",
  "redacted": [
    {
      "name": {
        "description": "Personal e-mail information"
      },
      "reason": {
        "description": "Personal data"
      },
      "prePath": "$.entities[?(@.handle=='ORG-Sa508-RIPE')].vcardArray[1][?(@[0]=='e-mail')]",
      "method": "removal"
    },
    {
      "name": {
        "description": "Personal e-mail information"
      },
      "reason": {
        "description": "Personal data"
      },
      "prePath": "$.entities[?(@.handle=='SZN5-RIPE')].vcardArray[1][?(@[0]=='e-mail')]",
      "method": "removal"
    },
    {
      "name": {
        "description": "Personal e-mail information"
      },
      "reason": {
        "description": "Personal data"
      },
      "prePath": "$.entities[?(@.handle=='AD10910-RIPE')].vcardArray[1][?(@[0]=='e-mail')]",
      "method": "removal"
    }
  ]
}

Contact details of private individuals are redacted.