Organization
Alliant Energy
ALLIANT-ENERGY
Registered
Jan 08, 2009
17 years ago
IPv4 Prefixes
8
4,096 addresses
IPv6 Prefixes
0
BGP Neighbours
4
4 upstream/peer · 0 downstream
Registration
AS Number AS21896 AS Name ALLIANT-ENERGY Organization Alliant Energy Organization ID ALLIA-101 Address 4902 North Biltmore Lane, Madison, WI, 53707-1007, United States Country United States (US) Registry ARIN Allocated Jan 08, 2009 Record Created Jan 08, 2009 Last Updated Mar 02, 2012 Status
active
WHOIS Server whois.arin.net AS Description ALLIANT-ENERGY - Alliant Energy, US Abuse Email [email protected] Abuse Phone +1-608-458-4357;extPlease ask for Data Networks On Call IPv4 Prefixes
8 prefixes · 4,096 addresses Routing data as of 2026-10-09 00:00 UTC
| Prefix | Range | Addresses |
|---|---|---|
| 198.7.38.0/23 | 198.7.38.0 – 198.7.39.255 | 512 |
| 198.7.42.0/23 | 198.7.42.0 – 198.7.43.255 | 512 |
| 198.7.44.0/23 | 198.7.44.0 – 198.7.45.255 | 512 |
| 198.7.46.0/23 | 198.7.46.0 – 198.7.47.255 | 512 |
| 207.71.128.0/23 | 207.71.128.0 – 207.71.129.255 | 512 |
| 207.71.134.0/23 | 207.71.134.0 – 207.71.135.255 | 512 |
| 207.71.136.0/23 | 207.71.136.0 – 207.71.137.255 | 512 |
| 207.71.142.0/23 | 207.71.142.0 – 207.71.143.255 | 512 |
IPv6 Prefixes
This AS does not currently announce any IPv6 prefixes.
BGP Neighbours
4 unique neighbours · 4 upstream/peer · 0 downstream. A neighbour can be seen on more than one side. Rows are ordered by AS paths: the number of BGP paths seen by RIPE RIS that contain the adjacency. Sightings count each IPv4/IPv6 route with the adjacency once per RIS peer that sees it (routes × peers), so they show how widely it is seen, not how many distinct routes it carries. Networks seen to the left of this AS in BGP paths, toward the route collectors — typically its transit providers (upstreams) and peers. Upstream & peer side (4)
Raw RDAP Response
{
"endAutnum": 21896,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2025-02-14T10:22:47-05:00"
},
{
"eventAction": "registration",
"eventDate": "2008-12-29T16:00:03-05:00"
}
],
"handle": "DNA51-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/DNA51-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21896"
},
{
"href": "https://whois.arin.net/rest/poc/DNA51-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21896"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"ARIN has attempted to validate the data for this POC, but has received no response from the POC since 2026-02-14"
],
"title": "Unvalidated POC"
}
],
"roles": [
"abuse",
"administrative",
"technical"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"adr",
{
"label": "4902 North Biltmore Lane\nMadison\nWI\n53718\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
{},
"text",
"Data Networks Admin"
],
[
"org",
{},
"text",
"Alliant Energy"
],
[
"kind",
{},
"text",
"group"
],
[
"email",
{},
"text",
"[email protected]"
],
[
"email",
{},
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-608-458-4357;extPlease ask for Data Networks On Call"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2020-12-08T15:57:57-05:00"
},
{
"eventAction": "registration",
"eventDate": "2008-12-30T07:31:25-05:00"
}
],
"handle": "ALLIA-101",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/ALLIA-101",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21896"
},
{
"href": "https://whois.arin.net/rest/org/ALLIA-101",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21896"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"Standard NOC hours are 7am to 5pm CST"
],
"title": "Registration Comments"
}
],
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"fn",
{},
"text",
"Alliant Energy"
],
[
"adr",
{
"label": "4902 North Biltmore Lane\nMadison\nWI\n53707-1007\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
{},
"text",
"org"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2012-03-02T08:03:18-05:00"
},
{
"eventAction": "registration",
"eventDate": "2009-01-08T13:22:20-05:00"
}
],
"handle": "AS21896",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/21896",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21896"
},
{
"href": "https://whois.arin.net/rest/asn/AS21896",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21896"
}
],
"name": "ALLIANT-ENERGY",
"notices": [
{
"description": [
"By using the ARIN RDAP/Whois service, you are agreeing to the RDAP/Whois Terms of Use"
],
"links": [
{
"href": "https://www.arin.net/resources/registry/whois/tou/",
"rel": "terms-of-service",
"type": "text/html",
"value": "https://rdap.arin.net/registry/autnum/21896"
}
],
"title": "Terms of Service"
},
{
"description": [
"If you see inaccuracies in the results, please visit: "
],
"links": [
{
"href": "https://www.arin.net/resources/registry/whois/inaccuracy_reporting/",
"rel": "inaccuracy-report",
"type": "text/html",
"value": "https://rdap.arin.net/registry/autnum/21896"
}
],
"title": "Whois Inaccuracy Reporting"
},
{
"description": [
"Copyright 1997-2026, American Registry for Internet Numbers, Ltd."
],
"title": "Copyright Notice"
}
],
"objectClassName": "autnum",
"port43": "whois.arin.net",
"rdapConformance": [
"nro_rdap_profile_0",
"rdap_level_0",
"nro_rdap_profile_asn_flat_0"
],
"startAutnum": 21896,
"status": [
"active"
]
} Contact details of private individuals are redacted.