ASN AS20404 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS20404?

AS20404 is listed under NRG Energy, Inc..

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.

AS20404 NRG Energy, Inc. | IPGeolocation.io

ASN Lookup Tool

NRG Energy, Inc. nrg.com

US 7 Routes

AS Data

AS20404

AS20404 – NRG Energy, Inc.

AS Number	20404
AS Name	AS20404
Organization	NRG Energy, Inc.(ne-29)
Country	US
Website	nrg.com
Number of IPv4 Routes	7
Number of IPv6 Routes	0
ASN type	BUSINESS
Registry	ARIN
Date Allocated	2001-05-03

ASN Intelligence API for production workflows

Use ASN data for AS20404 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
158.81.168.0/24	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	256
158.81.210.0/23	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	512
158.81.252.0/24	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	256
158.81.153.0/24	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	256
158.81.160.0/24	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	256
158.81.208.0/23	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	512
158.81.251.0/24	AS20404	NRG Energy, Inc.	NRG Energy, Inc.	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:       20404
ASName:         AS20404
ASHandle:       AS20404
RegDate:        2001-05-03
Updated:        2013-03-07    
Ref:            https://rdap.arin.net/registry/autnum/20404


OrgName:        NRG Energy, Inc.
OrgId:          NE-29
Address:        910 Louisiana Street
City:           Houston
StateProv:      TX
PostalCode:     77002
Country:        US
RegDate:        2013-02-22
Updated:        2022-04-19
Ref:            https://rdap.arin.net/registry/entity/NE-29


OrgAbuseHandle: NETWO3117-ARIN
OrgAbuseName:   Network Services
OrgAbusePhone:  +1-832-357-3000 
OrgAbuseEmail:  Corp_NetOps_DL@nrg.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/NETWO3117-ARIN

OrgTechHandle: NETWO3117-ARIN
OrgTechName:   Network Services
OrgTechPhone:  +1-832-357-3000 
OrgTechEmail:  Corp_NetOps_DL@nrg.com
OrgTechRef:    https://rdap.arin.net/registry/entity/NETWO3117-ARIN

OrgNOCHandle: NETWO3117-ARIN
OrgNOCName:   Network Services
OrgNOCPhone:  +1-832-357-3000 
OrgNOCEmail:  Corp_NetOps_DL@nrg.com
OrgNOCRef:    https://rdap.arin.net/registry/entity/NETWO3117-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
AS46887	Crown Castle Fiber LLC	US
AS6461	Zayo Bandwidth	US

Upstreams

AS Number	Description	Country
AS46887	Crown Castle Fiber LLC	US
AS6461	Zayo Bandwidth	US