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AS398572
MONOLITHICPOWER-SJC - Monolithic Power Systems,Inc Announcing routesAS nameMONOLITHICPOWER-SJC
OrganisationMonolithic Power Systems,Inc
Registry (RIR)ARIN
HandleAS398572
RangeAS398572
Registered14 Jul 2020
Last changed14 Jul 2020
Abuse contact[email protected]
2IPv4 prefixes
0IPv6 prefixes
3Upstreams
0Downstreams
Upstreams
| AS | Network name | Visibility |
|---|---|---|
| AS36734 | PAXIO-SFBA - Paxio Inc. | 261 |
| AS33667 | CMCS - Comcast Cable Communications, LLC | 246 |
| AS33651 | CMCS - Comcast Cable Communications, LLC | 9 |
Downstreams
None seen.
IPv4 prefixes (2)
RPKI-validate all prefixes of AS398572
Contacts
| Role | Name | Handle | Email / phone | Address |
|---|---|---|---|---|
| registrant | Monolithic Power Systems,Inc | MPS-302 | 79 Great Oaks Blvd, San Jose, CA, 95119, United States | |
| technical, abuse, administrative, dns, routing, noc | MPS IT | MPSIT-ARIN | [email protected], +1-408-826-0685 | 79 Great Oaks Blvd, San Jose, CA, 95119, United States |
Raw registry response
{
"endAutnum": 398572,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2025-12-03T16:23:34-05:00"
},
{
"eventAction": "registration",
"eventDate": "2023-11-29T18:30:10-05:00"
}
],
"handle": "MPSIT-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/MPSIT-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/398572"
},
{
"href": "https://whois.arin.net/rest/poc/MPSIT-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/398572"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical",
"abuse",
"administrative",
"dns",
"routing",
"noc"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "79 Great Oaks Blvd\nSan Jose\nCA\n95119\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"MPS IT"
],
[
"org",
[],
"text",
"Monolithic Power Systems"
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-408-826-0685"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2024-11-25T11:09:46-05:00"
},
{
"eventAction": "registration",
"eventDate": "2020-06-18T09:46:56-04:00"
}
],
"handle": "MPS-302",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/MPS-302",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/398572"
},
{
"href": "https://whois.arin.net/rest/org/MPS-302",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/398572"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"https://www.monolithicpower.com"
],
"title": "Registration Comments"
}
],
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"fn",
[],
"text",
"Monolithic Power Systems,Inc"
],
[
"adr",
{
"label": "79 Great Oaks Blvd\nSan Jose\nCA\n95119\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
[],
"text",
"org"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2020-07-14T12:54:31-04:00"
},
{
"eventAction": "registration",
"eventDate": "2020-07-14T12:54:31-04:00"
}
],
"handle": "AS398572",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/398572",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/398572"
},
{
"href": "https://whois.arin.net/rest/asn/AS398572",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/398572"
}
],
"name": "MONOLITHICPOWER-SJC",
"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/398572"
}
],
"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/398572"
}
],
"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": 398572,
"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.