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AS21508
COMCAST-21508 - Comcast Cable Communications, LLC Announcing routesAS nameCOMCAST-21508
OrganisationComcast Cable Communications, LLC
Registry (RIR)ARIN
HandleAS21508
RangeAS21508
Registered16 May 2001
Last changed26 Jan 2021
Abuse contact[email protected]
17IPv4 prefixes
61IPv6 prefixes
1Upstreams
49Downstreams
Upstreams
| AS | Network name | Visibility |
|---|---|---|
| AS7922 | COMCAST-7922 - Comcast Cable Communications, LLC | 3915 |
Downstreams
| AS | Network name | Visibility |
|---|---|---|
| AS13335 | CLOUDFLARENET - Cloudflare, Inc. | 272 |
| AS54113 | FASTLY - Fastly, Inc. | 188 |
| AS400114 | APOG-RBC - Apogee Telecom Inc. | 152 |
| AS40641 | MGWTEL - MGW Telephone Company, Inc. | 148 |
| AS36364 | MHSNET - Mary Washington Hospital, Inc. | 146 |
| AS396083 | ARVUS-160-84 - Framatome Inc. | 146 |
| AS402549 | TERRASERVERS-NET - Terraservers | 145 |
| AS399938 | BHE-TRANSIT - Berkshire Hathaway Energy Company | 144 |
| AS15297 | EPLUS-ASN - EPLUS, Inc. | 143 |
| AS399099 | PCPS-ASN - petersburg city public schools | 143 |
| AS54219 | SCHAWK-INC - Matthews International Corporation | 143 |
| AS54883 | CORVA - City of Richmond, Virginia | 143 |
| AS32540 | HP-HOOD - HP Hood | 142 |
| AS36040 | YOUTUBE - Google LLC | 142 |
| AS394058 | TELOSC-ASH - Telos Corporation | 141 |
IPv4 prefixes (17)
IPv6 prefixes (61)
2001:559:875f::/482001:559:c10a::/482001:559:c460::/482001:559:c174::/482001:559:833e::/482001:559:c344::/482001:559:c0f6::/482001:559:c1a5::/482001:559:c45f::/482001:559:8201::/482001:559:85c1::/482001:559:c071::/482001:559:8416::/482001:559:3b9::/482001:559:72b::/482001:559:280::/482001:559:788::/482001:559:87b2::/482001:559:81d7::/482001:559:49b::/482001:559:c0f7::/482001:559:c1ca::/482001:559:37d::/482001:559:871a::/482001:559:49a::/482001:559:841c::/482001:559:c290::/482001:559:3c8::/482001:559:79d::/482001:559:82fd::/482001:559:c4f6::/482001:559:85ff::/482001:559:220::/482001:559:79e::/482001:559:c0::/482001:559:c515::/482001:559:c4db::/482001:559:3ac::/482001:559:7a7::/482001:559:f7::/482001:559:7db::/482001:559:8604::/482001:559:40a::/482001:559:c28f::/482001:559:5c9::/482001:559:5db::/482001:559:8773::/482001:559:c2a7::/482001:559:c3e9::/482001:559:243::/482001:559:8445::/482001:559:81bf::/482001:559:73c::/482001:559:8a::/482001:559:8535::/482001:559:c458::/482001:559:78a::/482001:559:c538::/482001:559:804c::/482001:559:81d8::/482001:559:53c::/48
RPKI-validate all prefixes of AS21508
Contacts
| Role | Name | Handle | Email / phone | Address |
|---|---|---|---|---|
| registrant | Comcast Cable Communications, LLC | CCCS | 1800 Bishops Gate Blvd, Mt Laurel, NJ, 08054, United States | |
| abuse | Network Abuse and Policy Observance | NAPO-ARIN | [email protected], +1-888-565-4329 | 1800 Bishops Gate Blvd, Mount Laurel, NJ, 08054, United States |
| routing | Routing | ROUTI25-ARIN | [email protected], +1-856-792-2300 | 1800 Bishops Gate Blvd, Mt Laurel, NJ, 08054, United States |
| technical, administrative | Comcast Cable Communications Inc | IC161-ARIN | [email protected], +1-856-792-2300 | 1800 Bishops Gate Blvd, Mount Laurel, NJ, 08054, United States |
Raw registry response
{
"endAutnum": 21508,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-05-21T11:13:31-04:00"
},
{
"eventAction": "registration",
"eventDate": "2002-09-30T17:45:14-04:00"
}
],
"handle": "NAPO-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/NAPO-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21508"
},
{
"href": "https://whois.arin.net/rest/poc/NAPO-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21508"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"This contact is to be used for network abuse, spam/phishing, and legally constituted requests for information or action. It is not for any other purpose."
],
"title": "Registration Comments"
}
],
"roles": [
"abuse"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1800 Bishops Gate Blvd\nMount Laurel\nNJ\n08054\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Network Abuse and Policy Observance"
],
[
"org",
[],
"text",
"Comcast Cable Communications, Inc."
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-888-565-4329"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-09-02T12:36:43-04:00"
},
{
"eventAction": "registration",
"eventDate": "2020-11-18T14:40:04-05:00"
}
],
"handle": "ROUTI25-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/ROUTI25-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21508"
},
{
"href": "https://whois.arin.net/rest/poc/ROUTI25-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21508"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"Issues related to Routing, RPKI, Route Registry.",
"Not monitored 24/7.",
"Please email, there is no available phone number."
],
"title": "Registration Comments"
}
],
"roles": [
"routing"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1800 Bishops Gate Blvd\nMt Laurel\nNJ\n08054\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Routing"
],
[
"org",
[],
"text",
"Comcast"
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-856-792-2300"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-09-21T12:18:12-04:00"
},
{
"eventAction": "registration",
"eventDate": "2002-06-12T11:30:41-04:00"
}
],
"handle": "IC161-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/IC161-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21508"
},
{
"href": "https://whois.arin.net/rest/poc/IC161-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21508"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"This is not an Abuse, Spam, or Legal notification POC.",
"Please use [email protected] for all security, takedown, and emergency issues. This IP Registration address cannot address those issues.",
"Please email, there is no available phone number."
],
"title": "Registration Comments"
}
],
"roles": [
"technical",
"administrative"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1800 Bishops Gate Blvd\nMount Laurel\nNJ\n08054\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Comcast Cable Communications Inc"
],
[
"org",
[],
"text",
"Comcast Cable Communications, Inc."
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-856-792-2300"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2020-11-18T14:58:28-05:00"
},
{
"eventAction": "registration",
"eventDate": "2001-09-18T00:00:00-04:00"
}
],
"handle": "CCCS",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/CCCS",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21508"
},
{
"href": "https://whois.arin.net/rest/org/CCCS",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21508"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"fn",
[],
"text",
"Comcast Cable Communications, LLC"
],
[
"adr",
{
"label": "1800 Bishops Gate Blvd\nMt Laurel\nNJ\n08054\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
[],
"text",
"org"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2021-01-25T15:20:02-05:00"
},
{
"eventAction": "registration",
"eventDate": "2001-05-16T00:00:00-04:00"
}
],
"handle": "AS21508",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/21508",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/21508"
},
{
"href": "https://whois.arin.net/rest/asn/AS21508",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/21508"
}
],
"name": "COMCAST-21508",
"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/21508"
}
],
"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/21508"
}
],
"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": 21508,
"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.