ASN AS26551 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS26551?

AS26551 is listed under Sargent & Lundy Engineers.

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.

AS26551 Sargent & Lundy Engineers

ASN Lookup Tool

Sargent & Lundy Engineers sargentlundy.com

US 5 Routes

AS Data

AS26551

AS26551 – Sargent & Lundy Engineers

AS Number	26551
AS Name	SARGENT-AND-LUNDY
Organization	Sargent & Lundy Engineers(sle-1)
Country	US
Website	sargentlundy.com
Number of IPv4 Routes	5
Number of IPv6 Routes	0
ASN type	BUSINESS
Registry	ARIN
Date Allocated	2002-10-15

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Use ASN data for AS26551 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
151.154.84.0/22	AS26551	Sargent & Lundy Engineers	Sargent & Lundy Engineers	1024
151.154.0.0/16	AS26551	Sargent & Lundy Engineers	Sargent & Lundy Engineers	65536
151.154.223.0/24	AS26551	Sargent & Lundy Engineers	Sargent & Lundy Engineers	256
151.154.128.0/20	AS26551	Sargent & Lundy Engineers	Sargent & Lundy Engineers	4096
151.154.103.0/24	AS26551	Sargent & Lundy Engineers	Sargent & Lundy Engineers	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:       26551
ASName:         SARGENT-AND-LUNDY
ASHandle:       AS26551
RegDate:        2002-10-15
Updated:        2012-03-02    
Ref:            https://rdap.arin.net/registry/autnum/26551


OrgName:        Sargent & Lundy Engineers
OrgId:          SLE-1
Address:        55 E. Monroe Street
City:           Chicago
StateProv:      IL
PostalCode:     60603
Country:        US
RegDate:        1991-07-30
Updated:        2025-12-28
Ref:            https://rdap.arin.net/registry/entity/SLE-1


OrgTechHandle: CB2411-ARIN
OrgTechName:   Berns, Christine 
OrgTechPhone:  +1-312-269-3598 
OrgTechEmail:  christine.m.berns@sargentlundy.com
OrgTechRef:    https://rdap.arin.net/registry/entity/CB2411-ARIN

OrgDNSHandle: CB2411-ARIN
OrgDNSName:   Berns, Christine 
OrgDNSPhone:  +1-312-269-3598 
OrgDNSEmail:  christine.m.berns@sargentlundy.com
OrgDNSRef:    https://rdap.arin.net/registry/entity/CB2411-ARIN

OrgDNSHandle: CHOUI16-ARIN
OrgDNSName:   Chouikh, Mohammed 
OrgDNSPhone:  +1-312-269-6379 
OrgDNSEmail:  mohammed.chouikh@sargentlundy.com
OrgDNSRef:    https://rdap.arin.net/registry/entity/CHOUI16-ARIN

OrgRoutingHandle: CB2411-ARIN
OrgRoutingName:   Berns, Christine 
OrgRoutingPhone:  +1-312-269-3598 
OrgRoutingEmail:  christine.m.berns@sargentlundy.com
OrgRoutingRef:    https://rdap.arin.net/registry/entity/CB2411-ARIN

OrgTechHandle: CHOUI16-ARIN
OrgTechName:   Chouikh, Mohammed 
OrgTechPhone:  +1-312-269-6379 
OrgTechEmail:  mohammed.chouikh@sargentlundy.com
OrgTechRef:    https://rdap.arin.net/registry/entity/CHOUI16-ARIN

OrgRoutingHandle: CHOUI16-ARIN
OrgRoutingName:   Chouikh, Mohammed 
OrgRoutingPhone:  +1-312-269-6379 
OrgRoutingEmail:  mohammed.chouikh@sargentlundy.com
OrgRoutingRef:    https://rdap.arin.net/registry/entity/CHOUI16-ARIN

OrgAbuseHandle: CB2411-ARIN
OrgAbuseName:   Berns, Christine 
OrgAbusePhone:  +1-312-269-3598 
OrgAbuseEmail:  christine.m.berns@sargentlundy.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/CB2411-ARIN

OrgAbuseHandle: CHOUI16-ARIN
OrgAbuseName:   Chouikh, Mohammed 
OrgAbusePhone:  +1-312-269-6379 
OrgAbuseEmail:  mohammed.chouikh@sargentlundy.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/CHOUI16-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
AS2734	CoreSite	US
AS3549	Level 3 Communications, Inc. (GBLX)	US
AS3356	Level 3 Parent, LLC	US
AS6461	Zayo Bandwidth	US

Upstreams

AS Number	Description	Country
AS2734	CoreSite	US
AS3356	Level 3 Parent, LLC	US
AS6461	Zayo Bandwidth	US