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AS4
ISI-AS - University of Southern California Announcing routesAS nameISI-AS
OrganisationUniversity of Southern California
Registry (RIR)ARIN
HandleAS4
RangeAS4
Registered22 Feb 1984
Last changed29 Sep 2023
Abuse contact[email protected]
45IPv4 prefixes
8IPv6 prefixes
11Upstreams
3Downstreams
Upstreams
| AS | Network name | Visibility |
|---|---|---|
| AS567 | ASN-LNET-AS - Los Nettos | 295 |
| AS226 | LOS-NETTOS-AS - Los Nettos | 262 |
| AS10886 | MAX-GIGAPOP - University of Maryland | 225 |
| AS174 | COGENT-174 - Cogent Communications, LLC | 219 |
| AS266625 | AS266625 - WCA TELECOM | 120 |
| AS266306 | AS266306 - CENTRALNETT SERVICOS LTDA | 40 |
| AS275860 | AS275860 - FJOBA3 | 22 |
| AS400215 | SAMBANOVA - Sambanova Systems, Inc. | 21 |
| AS37358 | BitCo - BitCo | 20 |
| AS30844 | LIQUID-AS Liquid Telecommunications Ltd | 4 |
| AS58821 | IDNIC-LJN-AS-ID - PT Lintas Jaringan Nusantara | 1 |
IPv4 prefixes (45)
128.9.64.0/20170.79.218.0/23128.9.192.0/18128.9.80.0/20128.9.122.0/24206.117.27.0/24128.9.37.0/24128.9.30.0/24128.9.127.0/24128.9.34.0/24128.9.31.0/24198.32.16.0/24128.9.19.0/24128.9.17.0/24128.9.46.0/24128.9.40.0/24128.9.123.0/24128.9.117.0/24128.9.35.0/24128.9.32.0/20128.9.18.0/24128.9.38.0/24165.140.13.0/24206.117.6.0/24128.9.112.0/20128.9.128.0/20206.117.31.0/24128.9.26.0/24128.9.48.0/20128.9.16.0/24128.9.113.0/24128.9.144.0/20206.117.37.0/24128.9.43.0/24128.9.28.0/23128.9.36.0/24165.140.12.0/24128.9.160.0/20128.9.0.0/20128.9.96.0/20128.9.176.0/20165.140.14.0/24128.9.44.0/24128.9.47.0/24191.7.35.0/24
IPv6 prefixes (8)
RPKI-validate all prefixes of AS4
Contacts
| Role | Name | Handle | Email / phone | Address |
|---|---|---|---|---|
| registrant | University of Southern California | USC-32-Z | Information Sciences Institute, 4676 Admiralty Way, Suite 1001, Marina del Rey, CA, 90292, United States | |
| technical, abuse, administrative | IPC Computing Services | ACT-ORG-ARIN | [email protected], +1-310-448-8289 | 4676 Admiralty Way, Suite 1001, Marina del Rey, CA, 90292, United States |
Raw registry response
{
"endAutnum": 4,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-07-07T13:38:04-04:00"
}
],
"handle": "ACT-ORG-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/ACT-ORG-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/4"
},
{
"href": "https://whois.arin.net/rest/poc/ACT-ORG-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/4"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical",
"abuse",
"administrative"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "4676 Admiralty Way, Suite 1001\nMarina del Rey\nCA\n90292\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"IPC Computing Services"
],
[
"org",
[],
"text",
"USC/Information Sciences Institute"
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-310-448-8289"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2023-09-21T13:24:09-04:00"
},
{
"eventAction": "registration",
"eventDate": "2023-09-08T09:58:57-04:00"
}
],
"handle": "USC-32-Z",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/USC-32-Z",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/4"
},
{
"href": "https://whois.arin.net/rest/org/USC-32-Z",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/4"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"fn",
[],
"text",
"University of Southern California"
],
[
"adr",
{
"label": "Information Sciences Institute\n4676 Admiralty Way, Suite 1001\nMarina del Rey\nCA\n90292\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
[],
"text",
"org"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2023-09-29T04:49:38-04:00"
},
{
"eventAction": "registration",
"eventDate": "1984-02-22T00:00:00-05:00"
}
],
"handle": "AS4",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/4",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/4"
},
{
"href": "https://whois.arin.net/rest/asn/AS4",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/4"
}
],
"name": "ISI-AS",
"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/4"
}
],
"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/4"
}
],
"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": 4,
"status": [
"active"
]
}Results come from public internet registries and live global routing data. Results are cached for up to an hour. Lookups are logged with your IP address to prevent abuse — see our Privacy Policy.