Report for 4004

Name

COGENT-4000 - Cogent Communications, LLC, US

AS Adjacency Report

In the context of this report "Upstream" indicates that there is an adjacent AS that lines between the BGP table collection point (in this case at AS2.0) and the specified AS. Similarly, "Downstream" refers to an adjacent AS that lies beyond the specified AS. This upstream / downstream categorisation is strictly a description relative topology, and should not be confused with provider / customer / peer inter-AS relationships.

4004 COGENT-4000 - Cogent Communications, LLC, US

  Adjacency:     3  Upstream:     2  Downstream:     1
  Upstream Adjacent AS list
    AS6461          ZAYO-6461 - Zayo Bandwidth, US
    AS5511          OPENTRANSIT, FR
  Downstream Adjacent AS list
    AS51964         ORANGE-BUSINESS-SERVICES-IPSN-ASN, US

Announced Prefixes

Rank  AS       Type    Originate Addr Space  (pfx)   Transit Addr space  (pfx)  Description
58213 AS4004         ORG+TRN Originate:        256 /24.00  Transit:     105984 /15.31 COGENT-4000 - Cogent Communications, LLC, US

Aggregation Suggestions

        Filter: Aggregates, Specifics

This report does not take into account conditions local to each origin AS in terms of policy or traffic engineering requirements, so this is an approximate guideline as to aggregation possibilities.

 Rank AS            AS Name                                      Current  Wthdw  Aggte  Annce Redctn       %
31379 AS4004        COGENT-4000 - Cogent Communications, LLC, US       1      0      0      1      0   0.00%


  Prefix               AS Path                              Aggregation Suggestion
  57.66.70.0/24        4777 2497 5511 4004    

Advertisements that are fragments of the original RIR allocation (more specifics) originated by this AS.

AS4004   1 More Specifics   1 Total Advertisements   COGENT-4000 - Cogent Communications, LLC, US
    57.66.70.0/24                 57.66.0.0/15

Whois Entry

whois: 402332

IANA has recorded AS4004 as originally allocated by 
/usr/bin/whois -h jwhois.apnic.netr "AS4004\n             
             #
             # ARIN WHOIS data and services are subject to the Terms of Use
             # available at: https://www.arin.net/resources/registry/whois/tou/
             #
             # If you see inaccuracies in the results, please report at
             # https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
             #
             # Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
             #
             
             
             ASNumber:       4000 - 4005
             ASName:         COGENT-4000
             ASHandle:       AS4000
             RegDate:        1994-11-04
             Updated:        2025-12-23
             Ref:            https://rdap.arin.net/registry/autnum/4000
             
             
             
             OrgName:        Cogent Communications, LLC
             OrgId:          COGC
             Address:        2450 N Street NW
             City:           Washington
             StateProv:      DC
             PostalCode:     20037
             Country:        US
             RegDate:        2000-05-30
             Updated:        2025-09-23
             Comment:        Geofeed https://geofeed.cogentco.com/geofeed.csv
             Ref:            https://rdap.arin.net/registry/entity/COGC
             
             ReferralServer:  rwhois://rwhois.cogentco.com:4321
             
             OrgTechHandle: IPALL-ARIN
             OrgTechName:   IP Allocation
             OrgTechPhone:  +1-877-875-4311 
             OrgTechEmail:  ipalloc@cogentco.com
             OrgTechRef:    https://rdap.arin.net/registry/entity/IPALL-ARIN
             
             OrgAbuseHandle: COGEN-ARIN
             OrgAbuseName:   Cogent Abuse
             OrgAbusePhone:  +1-877-875-4311 
             OrgAbuseEmail:  abuse@cogentco.com
             OrgAbuseRef:    https://rdap.arin.net/registry/entity/COGEN-ARIN
             
             OrgNOCHandle: ZC108-ARIN
             OrgNOCName:   Cogent Communications
             OrgNOCPhone:  +1-877-875-4311 
             OrgNOCEmail:  noc@cogentco.com
             OrgNOCRef:    https://rdap.arin.net/registry/entity/ZC108-ARIN
             
             
             #
             # ARIN WHOIS data and services are subject to the Terms of Use
             # available at: https://www.arin.net/resources/registry/whois/tou/
             #
             # If you see inaccuracies in the results, please report at
             # https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
             #
             # Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
             #
             
             
             
             Found a referral to rwhois.cogentco.com:4321.
             
             %rwhois V-1.5:0010b0:00 rwhois.cogentco.com (CGNT rwhoisd 1.2.2)
             %error 230 No objects found