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AS5653
UCSF - University of California San Francisco Announcing routesAS nameUCSF
OrganisationUniversity of California San Francisco
Registry (RIR)ARIN
HandleAS5653
RangeAS5653
Registered27 Jul 1995
Last changed26 Feb 2026
Abuse contact[email protected]
17IPv4 prefixes
0IPv6 prefixes
3Upstreams
0Downstreams
Upstreams
| AS | Network name | Visibility |
|---|---|---|
| AS2152 | CENIC-2152 - CENIC | 455 |
| AS6461 | ZAYO-6461 - Zayo Bandwidth | 242 |
| AS2153 | CENIC-2153 - CENIC | 11 |
Downstreams
None seen.
IPv4 prefixes (17)
RPKI-validate all prefixes of AS5653
Contacts
| Role | Name | Handle | Email / phone | Address |
|---|---|---|---|---|
| registrant | University of California San Francisco | UCSF-Z | Room 602, 1855 Folsom Street, San Francisco, CA, 94143-0225, United States | |
| technical | Steve Young | YOUNG1436-ARIN | [email protected], +1-415-476-0869, +1-415-716-5570 | 1855 Folsom Street, San Francisco, CA, 94103, United States |
| abuse | UCSF ITS Information Security Services | UIISS-ARIN | [email protected], +1-415-514-4100;ext2 | 1855 Folsom Street , Suite 301, San Francisco, CA, 94103-0272, United States |
| administrative, technical | Tom Chen | CHENT14-ARIN | [email protected], +1-415-353-3990, +1-415-860-4051 | 1855 Folsom St, #601, San Francisco, CA, 94143, United States |
Raw registry response
{
"endAutnum": 5653,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-05-18T11:28:55-04:00"
},
{
"eventAction": "registration",
"eventDate": "2023-05-12T14:56:18-04:00"
}
],
"handle": "YOUNG1436-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/YOUNG1436-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5653"
},
{
"href": "https://whois.arin.net/rest/poc/YOUNG1436-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5653"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1855 Folsom Street\nSan Francisco\nCA\n94103\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Steve Young"
],
[
"n",
[],
"text",
[
"Young",
"Steve",
"",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-415-476-0869"
],
[
"tel",
{
"type": [
"work",
"cell"
]
},
"text",
"+1-415-716-5570"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2018-11-26T12:41:42-05:00"
},
{
"eventAction": "registration",
"eventDate": "2004-05-05T21:00:06-04:00"
}
],
"handle": "UIISS-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/UIISS-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5653"
},
{
"href": "https://whois.arin.net/rest/poc/UIISS-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5653"
}
],
"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 2019-11-26"
],
"title": "Unvalidated POC"
}
],
"roles": [
"abuse"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1855 Folsom Street\r\nSuite 301\nSan Francisco\nCA\n94103-0272\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"UCSF ITS Information Security Services"
],
[
"org",
[],
"text",
"UCSF"
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-415-514-4100;ext2"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-06-01T19:20:10-04:00"
},
{
"eventAction": "registration",
"eventDate": "2021-03-18T17:33:03-04:00"
}
],
"handle": "CHENT14-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/CHENT14-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5653"
},
{
"href": "https://whois.arin.net/rest/poc/CHENT14-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5653"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"administrative",
"technical"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1855 Folsom St, #601\nSan Francisco\nCA\n94143\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Tom Chen"
],
[
"n",
[],
"text",
[
"Chen",
"Tom",
"",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-415-353-3990"
],
[
"tel",
{
"type": [
"work",
"cell"
]
},
"text",
"+1-415-860-4051"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2023-08-22T21:09:45-04:00"
},
{
"eventAction": "registration",
"eventDate": "2023-08-22T21:09:45-04:00"
}
],
"handle": "UCSF-Z",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/UCSF-Z",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5653"
},
{
"href": "https://whois.arin.net/rest/org/UCSF-Z",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5653"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"fn",
[],
"text",
"University of California San Francisco"
],
[
"adr",
{
"label": "Room 602\n1855 Folsom Street\nSan Francisco\nCA\n94143-0225\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
[],
"text",
"org"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-02-26T13:14:13-05:00"
},
{
"eventAction": "registration",
"eventDate": "1995-07-27T00:00:00-04:00"
}
],
"handle": "AS5653",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/5653",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5653"
},
{
"href": "https://whois.arin.net/rest/asn/AS5653",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5653"
}
],
"name": "UCSF",
"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/5653"
}
],
"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/5653"
}
],
"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": 5653,
"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.