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AS51257 CERIZ SASU | IPGeolocation.io

Q: Why is WHOIS data shown for an ASN?

WHOIS data provides registration and contact context for ASN ownership, administration, and operational reference.

ASN Lookup Tool

CERIZ SASU fair-telecom.fr

FR 3 Routes

AS Data

AS51257

AS51257 – CERIZ SASU

AS Number	51257
AS Name	CERIZ
Organization	CERIZ SASU (org-cs398-ripe)
Country	FR
Website	fair-telecom.fr
Number of IPv4 Routes	1
Number of IPv6 Routes	2
ASN type	BUSINESS
Allocation Status	ASSIGNED
Registry	RIPE
Date Allocated	2016-01-05

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Use ASN data for AS51257 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
171.22.146.0/24	AS51257	CERIZ SASU	CERIZ SASU	256
2a05:d80:4000::/48	AS51257	CERIZ SASU	CERIZ SASU	~1×10²⁴
2a05:d80::/29	AS51257	CERIZ SASU	CERIZ SASU	~634×10²⁷

Raw Whois Response

% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See https://docs.db.ripe.net/terms-conditions.html

% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.

% Information related to 'AS50893 - AS51311'

as-block:       AS50893 - AS51311
descr:          RIPE NCC ASN block
remarks:        These AS Numbers are assigned to network operators in the RIPE NCC service region.
mnt-by:         RIPE-NCC-HM-MNT
created:        2024-12-10T14:54:30Z
last-modified:  2024-12-10T14:54:30Z
source:         RIPE

% Information related to 'AS51257'

% Abuse contact for 'AS51257' is 'jerome@fair-telecom.fr'

aut-num:        AS51257
as-name:        CERIZ
org:            ORG-CS398-RIPE
import:         from AS29075 accept ANY
export:         to AS29075 announce AS-CERIZ
admin-c:        JN2000-RIPE
tech-c:         JN2000-RIPE
status:         ASSIGNED
mnt-by:         RIPE-NCC-END-MNT
mnt-by:         MNT-CERIZ
created:        2016-01-05T10:49:07Z
last-modified:  2024-01-27T11:38:25Z
source:         RIPE

organisation:   ORG-CS398-RIPE
org-name:       CERIZ SASU
country:        FR
org-type:       LIR
address:        16, rue Amp�re
address:        95300
address:        Pontoise
address:        FRANCE
phone:          +33619312714
admin-c:        JN2000-RIPE
tech-c:         JN2000-RIPE
abuse-c:        AR34863-RIPE
mnt-ref:        MNT-CERIZ
mnt-ref:        RIPE-NCC-HM-MNT
mnt-by:         RIPE-NCC-HM-MNT
mnt-by:         MNT-CERIZ
created:        2016-01-04T14:42:36Z
last-modified:  2023-06-01T11:22:13Z
source:         RIPE # Filtered

person:         Nicolle Jerome
address:        Ste. FAIR-TELECOM
address:        10, rue de Penthivi�re
address:        75008 Paris
address:        FRANCE
phone:          +33619312714
remarks:
remarks:        PGPKEY-06A68A1B
nic-hdl:        JN2000-RIPE
mnt-by:         MNT-CERIZ
mnt-by:         FAIR-TELECOM-MNT
created:        2010-02-18T15:51:16Z
last-modified:  2025-12-29T10:01:17Z
source:         RIPE # Filtered

% This query was served by the RIPE Database Query Service version 1.121.2 (DEXTER)

Parsed Whois Response

{
  "status" : true,
  "whois_server" : "whois.ripe.net",
  "as_blocks" : [ {
    "as_block" : "AS50893 - AS51311",
    "description" : [ "RIPE NCC ASN block" ],
    "remarks" : [ "These AS Numbers are assigned to network operators in the RIPE NCC service region." ],
    "mnt_by" : [ "RIPE-NCC-HM-MNT" ],
    "date_created" : "2024-12-10",
    "date_updated" : "2024-12-10",
    "source" : "RIPE"
  } ],
  "aut_nums" : [ {
    "aut_num" : "AS51257",
    "as_name" : "CERIZ",
    "status" : "ASSIGNED",
    "import" : [ "from AS29075 accept ANY" ],
    "export" : [ "to AS29075 announce AS-CERIZ" ],
    "organization" : "ORG-CS398-RIPE",
    "admin_contacts" : [ "JN2000-RIPE" ],
    "tech_contacts" : [ "JN2000-RIPE" ],
    "mnt_by" : [ "RIPE-NCC-END-MNT", "MNT-CERIZ" ],
    "date_created" : "2016-01-05",
    "date_updated" : "2024-01-27",
    "source" : "RIPE"
  } ],
  "organization" : {
    "handle" : "ORG-CS398-RIPE",
    "name" : "CERIZ SASU",
    "type" : "LIR",
    "address" : [ "16, rue Amp?re", "95300", "Pontoise", "FRANCE" ],
    "street" : "Rue Amp?re",
    "city" : "Pontoise",
    "zip_code" : "95300",
    "country" : [ "FR" ],
    "phone" : [ "+33619312714" ],
    "admin_contacts" : [ "JN2000-RIPE" ],
    "tech_contacts" : [ "JN2000-RIPE" ],
    "abuse_contacts" : [ "AR34863-RIPE" ],
    "mnt_ref" : [ "MNT-CERIZ", "RIPE-NCC-HM-MNT" ],
    "mnt_by" : [ "RIPE-NCC-HM-MNT", "MNT-CERIZ" ],
    "date_created" : "2016-01-04",
    "date_updated" : "2023-06-01",
    "source" : "RIPE",
    "addressCountry" : "FRANCE"
  },
  "administrative_contacts" : [ {
    "handle" : "JN2000-RIPE",
    "name" : "Nicolle Jerome",
    "address" : [ "Ste. FAIR-TELECOM", "10, rue de Penthivi?re", "75008 Paris", "FRANCE" ],
    "street" : "Rue De Penthivi?re",
    "city" : "Paris",
    "zip_code" : "75008",
    "country" : "FRANCE",
    "phone" : [ "+33619312714" ],
    "remarks" : [ "PGPKEY-06A68A1B" ],
    "mnt_by" : [ "MNT-CERIZ", "FAIR-TELECOM-MNT" ],
    "date_created" : "2010-02-18",
    "date_updated" : "2025-12-29",
    "source" : "RIPE",
    "addressCountry" : "FRANCE"
  } ],
  "technical_contacts" : [ {
    "handle" : "JN2000-RIPE",
    "name" : "Nicolle Jerome",
    "address" : [ "Ste. FAIR-TELECOM", "10, rue de Penthivi?re", "75008 Paris", "FRANCE" ],
    "street" : "Rue De Penthivi?re",
    "city" : "Paris",
    "zip_code" : "75008",
    "country" : "FRANCE",
    "phone" : [ "+33619312714" ],
    "remarks" : [ "PGPKEY-06A68A1B" ],
    "mnt_by" : [ "MNT-CERIZ", "FAIR-TELECOM-MNT" ],
    "date_created" : "2010-02-18",
    "date_updated" : "2025-12-29",
    "source" : "RIPE",
    "addressCountry" : "FRANCE"
  } ]
}

Peers

AS Number	Description	Country
AS29075	IELO LIAZO SERVICES SAS	FR
AS29075	IELO-LIAZO SERVICES SAS	FR

Upstreams

AS Number	Description	Country
AS29075	IELO LIAZO SERVICES SAS	FR

Frequently Asked Questions

What is ASN AS51257?

ASN AS51257 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS51257?

AS51257 is listed under CERIZ SASU.

What do peers, upstreams, and downstreams mean?

Peers are lateral network interconnections, upstreams are transit providers, and downstreams are customer networks receiving connectivity.

What are routes and IP ranges for an ASN?

Routes and IP ranges are the network prefixes announced by the ASN on the internet and show the address space it originates.

Why is WHOIS data included here?

WHOIS provides registration and contact context for ASN ownership, administration, and operational reference.

How can I access full ASN table data?

This page previews large ASN datasets. Use See more to load additional rows, and upgrade your plan to view complete peer, route, upstream, and downstream data.