ASN AS104 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS104?

AS104 is listed under University of Colorado at Boulder.

What do peers, upstreams, and downstreams mean in ASN data?

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 shown for an ASN?

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

How can I access the full ASN tables?

The page shows a preview of large ASN datasets. Use the page controls to load more rows, and upgrade to a paid plan for complete access.

AS104 University of Colorado at Boulder

ASN Lookup Tool

University of Colorado at Boulder colorado.edu

US 22 Routes

AS Data

AS104

AS104 – University of Colorado at Boulder

AS Number	104
AS Name	COLORADO-AS
Organization	University of Colorado at Boulder(ucab-2)
Country	US
Website	colorado.edu
Number of IPv4 Routes	20
Number of IPv6 Routes	2
ASN type	EDUCATION
Registry	ARIN
Date Allocated	1987-04-09

ASN Intelligence API for production workflows

Use ASN data for AS104 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

Access complete peers, upstreams, downstreams, routes, WHOIS, and contact intelligence via our API. Learn more

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
198.59.82.0/24	AS104	University of Colorado at Boulder	University of Colorado Boulder	256
198.11.16.0/20	AS104	University of Colorado at Boulder	University of Colorado Boulder	4096
192.12.245.0/24	AS104	University of Colorado at Boulder	University of Colorado	256
192.12.241.0/24	AS104	University of Colorado at Boulder	University of Colorado	256
204.228.80.0/24	AS104	University of Colorado at Boulder	University of Colorado Boulder	256
146.5.20.0/22	AS104	University of Colorado at Boulder	National Solar Observatory	1024
198.59.51.0/24	AS104	University of Colorado at Boulder	University of Colorado Boulder	256
198.59.83.0/24	AS104	University of Colorado at Boulder	University of Colorado Boulder	256
198.59.70.0/24	AS104	University of Colorado at Boulder	University of Colorado Boulder	256
128.138.0.0/16	AS104	University of Colorado at Boulder	University of Colorado	65536

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:       104
ASName:         COLORADO-AS
ASHandle:       AS104
RegDate:        1987-04-09
Updated:        2019-06-25    
Ref:            https://rdap.arin.net/registry/autnum/104


OrgName:        University of Colorado at Boulder
OrgId:          UCAB-2
Address:        Campus Box 455
City:           Boulder
StateProv:      CO
PostalCode:     80309-0455
Country:        US
RegDate:        1987-04-09
Updated:        2019-06-25
Ref:            https://rdap.arin.net/registry/entity/UCAB-2


OrgAbuseHandle: ABUSE306-ARIN
OrgAbuseName:   Abuse
OrgAbusePhone:  +1-303-735-4357 
OrgAbuseEmail:  abuse@colorado.edu
OrgAbuseRef:    https://rdap.arin.net/registry/entity/ABUSE306-ARIN

OrgTechHandle: CUBOU-ARIN
OrgTechName:   CUBoulder
OrgTechPhone:  +1-303-735-4357 
OrgTechEmail:  arinadmin@colorado.edu
OrgTechRef:    https://rdap.arin.net/registry/entity/CUBOU-ARIN

RAbuseHandle: ABUSE306-ARIN
RAbuseName:   Abuse
RAbusePhone:  +1-303-735-4357 
RAbuseEmail:  abuse@colorado.edu
RAbuseRef:    https://rdap.arin.net/registry/entity/ABUSE306-ARIN

RTechHandle: CUBOU-ARIN
RTechName:   CUBoulder
RTechPhone:  +1-303-735-4357 
RTechEmail:  arinadmin@colorado.edu
RTechRef:    https://rdap.arin.net/registry/entity/CUBOU-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

Peers

AS Number	Description	Country
AS3549	Level 3 Communications, Inc. (GBLX)	US
AS14041	University Corporation for Atmospheric Research	US
AS3356	Level 3 Parent, LLC	US

Upstreams

AS Number	Description	Country
AS14041	University Corporation for Atmospheric Research	US
AS3356	Level 3 Parent, LLC	US

Contacts

Email Contacts

arinadmin@colorado.edu

Abuse Contacts

abuse@colorado.edu