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AS31900 City of Thornton | 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

City of Thornton cityofthornton.net

US 1 Routes

AS Data

AS31900

AS31900 – City of Thornton

AS Number	31900
AS Name	CITYOFTHORNTON
Organization	City of Thornton (cityo-41)
Country	US
Website	cityofthornton.net
Number of IPv4 Routes	1
Number of IPv6 Routes	0
ASN type	GOVERNMENT
Registry	ARIN
Date Allocated	2004-01-20

ASN Intelligence API for production workflows

Use ASN data for AS31900 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
199.117.212.0/24	AS31900	City of Thornton	City of Thornton	256

Raw Whois Response

#
# 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:       31900
ASName:         CITYOFTHORNTON
ASHandle:       AS31900
RegDate:        2004-01-20
Updated:        2012-03-02
Ref:            https://rdap.arin.net/registry/autnum/31900


OrgName:        City of Thornton
OrgId:          CITYO-41
Address:        9500 Civic Center Drive
Address:        IT
City:           Thornton
StateProv:      CO
PostalCode:     80229
Country:        US
RegDate:        2003-10-27
Updated:        2011-09-24
Ref:            https://rdap.arin.net/registry/entity/CITYO-41


OrgAbuseHandle: NETWO392-ARIN
OrgAbuseName:   Network Operations
OrgAbusePhone:  +1-303-538-7690 
OrgAbuseEmail:  netadmin@cityofthornton.net
OrgAbuseRef:    https://rdap.arin.net/registry/entity/NETWO392-ARIN

OrgTechHandle: NETWO392-ARIN
OrgTechName:   Network Operations
OrgTechPhone:  +1-303-538-7690 
OrgTechEmail:  netadmin@cityofthornton.net
OrgTechRef:    https://rdap.arin.net/registry/entity/NETWO392-ARIN

RTechHandle: NETWO392-ARIN
RTechName:   Network Operations
RTechPhone:  +1-303-538-7690 
RTechEmail:  netadmin@cityofthornton.net
RTechRef:    https://rdap.arin.net/registry/entity/NETWO392-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.
#

Parsed Whois Response

{
  "status" : true,
  "whois_server" : "whois.arin.net",
  "aut_nums" : [ {
    "aut_num" : "31900",
    "as_handle" : "AS31900",
    "as_name" : "CITYOFTHORNTON",
    "tech_contacts" : [ "NETWO392-ARIN", "NETWO392-ARIN" ],
    "abuse_contacts" : [ "NETWO392-ARIN" ],
    "date_created" : "2004-01-20",
    "date_updated" : "2012-03-02",
    "source" : "https://rdap.arin.net/registry/autnum/31900"
  } ],
  "organization" : {
    "handle" : "CITYO-41",
    "name" : "City of Thornton",
    "address" : [ "9500 Civic Center Drive", "IT", "Thornton", "CO", "80229", "US" ],
    "street" : "Civic Center Drive It",
    "city" : "Thornton",
    "state" : "CO",
    "zip_code" : "80229",
    "country" : [ "US" ],
    "date_created" : "2003-10-27",
    "date_updated" : "2011-09-24",
    "source" : "https://rdap.arin.net/registry/entity/CITYO-41",
    "addressCountry" : "US"
  },
  "technical_contacts" : [ {
    "handle" : "NETWO392-ARIN",
    "name" : "Network Operations",
    "email" : [ "netadmin@cityofthornton.net" ],
    "phone" : [ "+1-303-538-7690" ],
    "source" : "https://rdap.arin.net/registry/entity/NETWO392-ARIN"
  } ],
  "abuse_contacts" : [ {
    "handle" : "NETWO392-ARIN",
    "name" : "Network Operations",
    "email" : [ "netadmin@cityofthornton.net" ],
    "phone" : [ "+1-303-538-7690" ],
    "source" : "https://rdap.arin.net/registry/entity/NETWO392-ARIN"
  } ]
}

Peers

AS Number	Description	Country
AS3356	Level 3 Parent, LLC	US

Upstreams

AS Number	Description	Country
AS3356	Level 3 Parent, LLC	US

Frequently Asked Questions

What is ASN AS31900?

ASN AS31900 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS31900?

AS31900 is listed under City of Thornton.

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.