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AS11891 City of San Leandro | 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 San Leandro sanleandro.org

US 1 Routes

AS Data

AS11891

AS11891 – City of San Leandro

AS Number	11891
AS Name	COSL-ASN-01
Organization	City of San Leandro(csl-533)
Country	US
Website	sanleandro.org
Number of IPv4 Routes	1
Number of IPv6 Routes	0
ASN type	GOVERNMENT
Registry	ARIN
Date Allocated	2024-04-01

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
12.21.101.0/24	AS11891	City of San Leandro	SAN LEANDRO UNIFIED SCHOOL DISTR	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:       11891
ASName:         COSL-ASN-01
ASHandle:       AS11891
RegDate:        2024-04-01
Updated:        2024-04-01    
Ref:            https://rdap.arin.net/registry/autnum/11891


OrgName:        City of San Leandro
OrgId:          CSL-533
Address:        835 E 14th Street
City:           San Leandro
StateProv:      CA
PostalCode:     94577
Country:        US
RegDate:        2016-08-19
Updated:        2025-06-06
Ref:            https://rdap.arin.net/registry/entity/CSL-533


OrgTechHandle: MCVIC5-ARIN
OrgTechName:   McVicker, Tim 
OrgTechPhone:  +1-510-577-3359 
OrgTechEmail:  TMcVicker@sanleandro.org
OrgTechRef:    https://rdap.arin.net/registry/entity/MCVIC5-ARIN

OrgAbuseHandle: SOUTH127-ARIN
OrgAbuseName:   Southern, Keith 
OrgAbusePhone:  +1-510-577-3339 
OrgAbuseEmail:  ksouthern@sanleandro.org
OrgAbuseRef:    https://rdap.arin.net/registry/entity/SOUTH127-ARIN

OrgTechHandle: RASHE18-ARIN
OrgTechName:   Rashedi, Sharif 
OrgTechPhone:  +1-510-387-9160 
OrgTechEmail:  srashedi@sanleandro.org
OrgTechRef:    https://rdap.arin.net/registry/entity/RASHE18-ARIN

OrgTechHandle: YUNGJ4-ARIN
OrgTechName:   Yung, Jesse 
OrgTechPhone:  +1-510-577-3326 
OrgTechEmail:  jyung@sanleandro.org
OrgTechRef:    https://rdap.arin.net/registry/entity/YUNGJ4-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
AS7018	AT&T Enterprises, LLC	US

Upstreams

AS Number	Description	Country
AS7018	AT&T Enterprises, LLC	US

Frequently Asked Questions

What is ASN AS11891?

ASN AS11891 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS11891?

AS11891 is listed under City of San Leandro.

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.