AS5739
University of California, Santa Cruz
ARIN US active Announced
More ASNs in the United States → Organization
University of California, Santa Cruz
Registered
Sep 13, 1995
31 years ago
IPv4 Prefixes
2
131,072 addresses
IPv6 Prefixes
1
65,536 × /48
BGP Neighbours
2
2 upstream/peer · 0 downstream
Registration
AS Number AS5739 Organization University of California, Santa Cruz Organization ID UCSC Address University of California, Santa Cruz, Information Technology Services, Communications Building, 620 Baskin Circle, Santa Cruz, CA, 95064, United States Country United States (US) Registry ARIN Allocated Sep 13, 1995 Record Created Sep 13, 1995 Last Updated Jun 29, 2011 Status
active
WHOIS Server whois.arin.net AS Description UCSC - University of California, Santa Cruz, US Abuse Email [email protected] Abuse Phone +1-831-459-2714 IPv4 Prefixes
2 prefixes · 131,072 addresses Routing data as of 2026-10-09 08:00 UTC
| Prefix | Range | Addresses |
|---|---|---|
| 128.114.0.0/16 | 128.114.0.0 – 128.114.255.255 | 65,536 |
| 169.233.0.0/16 | 169.233.0.0 – 169.233.255.255 | 65,536 |
IPv6 Prefixes
1 prefix · 65,536 × /48 Routing data as of 2026-10-09 08:00 UTC
| Prefix | Addresses |
|---|---|
| 2607:f5f0:: | 296 |
BGP Neighbours
2 unique neighbours · 2 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 (2)
Raw RDAP Response
{
"endAutnum": 5739,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2025-11-20T14:55:07-05:00"
},
{
"eventAction": "registration",
"eventDate": "2002-11-26T17:58:41-05:00"
}
],
"handle": "UCSCN1-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/UCSCN1-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5739"
},
{
"href": "https://whois.arin.net/rest/poc/UCSCN1-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5739"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"abuse"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"adr",
{
"label": "UCSC Information Technology Services\r\nCommunications Building\r\n620 Baskin Circle\nSanta Cruz\nCA\n95064\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
{},
"text",
"UCSC Security"
],
[
"org",
{},
"text",
"University of California, Santa Cruz"
],
[
"kind",
{},
"text",
"group"
],
[
"email",
{},
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-831-459-2714"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-06-01T15:04:29-04:00"
},
{
"eventAction": "registration",
"eventDate": "2002-11-26T17:58:41-05:00"
}
],
"handle": "UCSCN-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/UCSCN-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5739"
},
{
"href": "https://whois.arin.net/rest/poc/UCSCN-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5739"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical",
"administrative",
"noc"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"adr",
{
"label": "UCSC Information Technology Services\r\nCommunications Building\r\n620 Baskin Circle\nSanta Cruz\nCA\n95064\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
{},
"text",
"Network Operations Center"
],
[
"org",
{},
"text",
"University of California, Santa Cruz"
],
[
"kind",
{},
"text",
"group"
],
[
"email",
{},
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-831-459-2714"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-06-15T16:31:06-04:00"
},
{
"eventAction": "registration",
"eventDate": "1986-03-05T00:00:00-05:00"
}
],
"handle": "UCSC",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/UCSC",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5739"
},
{
"href": "https://whois.arin.net/rest/org/UCSC",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5739"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"fn",
{},
"text",
"University of California, Santa Cruz"
],
[
"adr",
{
"label": "University of California, Santa Cruz\r\nInformation Technology Services\r\nCommunications Building\r\n620 Baskin Circle\nSanta Cruz\nCA\n95064\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
{},
"text",
"org"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-06-01T15:04:29-04:00"
},
{
"eventAction": "registration",
"eventDate": "2002-11-26T17:58:41-05:00"
}
],
"handle": "UCSCN-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/UCSCN-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5739"
},
{
"href": "https://whois.arin.net/rest/poc/UCSCN-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5739"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"adr",
{
"label": "UCSC Information Technology Services\r\nCommunications Building\r\n620 Baskin Circle\nSanta Cruz\nCA\n95064\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
{},
"text",
"Network Operations Center"
],
[
"org",
{},
"text",
"University of California, Santa Cruz"
],
[
"kind",
{},
"text",
"group"
],
[
"email",
{},
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-831-459-2714"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2011-06-29T12:36:29-04:00"
},
{
"eventAction": "registration",
"eventDate": "1995-09-13T00:00:00-04:00"
}
],
"handle": "AS5739",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/5739",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/5739"
},
{
"href": "https://whois.arin.net/rest/asn/AS5739",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/5739"
}
],
"name": "UCSC",
"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/5739"
}
],
"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/5739"
}
],
"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": 5739,
"status": [
"active"
]
} Contact details of private individuals are redacted.