
21896 ALLIANT-ENERGY, US
Adjacency: 4 Upstream: 4 Downstream: 0
Upstream Adjacent AS list
AS393238 IMONC, US
AS40264 TWC-40264-WI-MN-UPPERMI-C3, US
AS4181 TDS-AS, US
AS3356 LEVEL3, US
Rank AS Type Originate Addr Space (pfx) Transit Addr space (pfx) Description 16966 AS21896 ORIGIN Originate: 4096 /20.00 Transit: 0 /0.00 ALLIANT-ENERGY, US
Aggregation Suggestions
Filter: Aggregates, Specifics
This report does not take into account conditions local to each origin AS in terms of policy or traffic engineering requirements, so this is an approximate guideline as to aggregation possibilities.
Rank AS AS Name Current Wthdw Aggte Annce Redctn % 21515 AS21896 ALLIANT-ENERGY, US 8 2 1 7 1 12.50% Prefix AS Path Aggregation Suggestion 198.7.38.0/23 293 4181 21896 198.7.42.0/23 293 4181 21896 198.7.44.0/22 293 4181 21896 + Announce - aggregate of 198.7.44.0/23 (293 4181 21896) and 198.7.46.0/23 (293 4181 21896) 198.7.44.0/23 293 4181 21896 - Withdrawn - aggregated with 198.7.46.0/23 (293 4181 21896) 198.7.46.0/23 293 4181 21896 - Withdrawn - aggregated with 198.7.44.0/23 (293 4181 21896) 207.71.128.0/23 3303 3356 21896 207.71.134.0/23 3303 3356 21896 207.71.136.0/23 3303 3356 21896 207.71.142.0/23 3303 3356 21896
Advertisements that are fragments of the original RIR allocation (more specifics) originated by this AS.
AS21896 22 More Specifics 22 Total Advertisements ALLIANT-ENERGY, US
198.7.38.0/23 198.7.32.0/20
198.7.38.0/24 198.7.32.0/20
198.7.42.0/23 198.7.32.0/20
198.7.42.0/24 198.7.32.0/20
198.7.43.0/24 198.7.32.0/20
198.7.44.0/23 198.7.32.0/20
198.7.44.0/24 198.7.32.0/20
198.7.45.0/24 198.7.32.0/20
198.7.46.0/23 198.7.32.0/20
198.7.46.0/24 198.7.32.0/20
198.7.47.0/24 198.7.32.0/20
207.71.128.0/23 207.71.128.0/19
207.71.128.0/24 207.71.128.0/19
207.71.129.0/24 207.71.128.0/19
207.71.134.0/23 207.71.128.0/19
207.71.135.0/24 207.71.128.0/19
207.71.136.0/23 207.71.128.0/19
207.71.136.0/24 207.71.128.0/19
207.71.137.0/24 207.71.128.0/19
207.71.142.0/23 207.71.128.0/19
207.71.142.0/24 207.71.128.0/19
207.71.143.0/24 207.71.128.0/19
whois: 402603
IANA has recorded AS21896 as originally allocated by
/usr/bin/whois -h jwhois.apnic.netr "AS21896\n
#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
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# If you see inaccuracies in the results, please report at
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# Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
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ASNumber: 21896
ASName: ALLIANT-ENERGY
ASHandle: AS21896
RegDate: 2009-01-08
Updated: 2012-03-02
Ref: https://rdap.arin.net/registry/autnum/21896
OrgName: Alliant Energy
OrgId: ALLIA-101
Address: 4902 North Biltmore Lane
City: Madison
StateProv: WI
PostalCode: 53707-1007
Country: US
RegDate: 2008-12-30
Updated: 2020-12-08
Comment: Standard NOC hours are 7am to 5pm CST
Ref: https://rdap.arin.net/registry/entity/ALLIA-101
OrgTechHandle: DNA51-ARIN
OrgTechName: Data Networks Admin
OrgTechPhone: +1-608-458-4357
OrgTechEmail: DL_IT_Data_Network-ALI@alliantenergy.com
OrgTechRef: https://rdap.arin.net/registry/entity/DNA51-ARIN
OrgAbuseHandle: DNA51-ARIN
OrgAbuseName: Data Networks Admin
OrgAbusePhone: +1-608-458-4357
OrgAbuseEmail: DL_IT_Data_Network-ALI@alliantenergy.com
OrgAbuseRef: https://rdap.arin.net/registry/entity/DNA51-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.
#