AS33651 — CMCS

AS33651 announces 189 IPv4 prefixes covering 2,268,160 addresses and 172 IPv6 prefixes.

About this network

CMCS is the AS handle for Comcast Cable Communications, LLC.

What it's used for

• The address space carries residential cable internet services, evidenced by reverse DNS entries like c-24-4-128-0.hsd1.ca.comcast.net and netnames such as BAYAREA-CPE-23 and SFBA-CPE-49.
• With 2,268,160 IPv4 addresses announced across 189 prefixes and 143 observed neighbours, the high address-to-neighbour ratio indicates a large access/eyeball network rather than a transit provider.

Notable

• Registrants consistently identify as Comcast Cable Communications, LLC or its subsidiaries (e.g., Comcast Cable Communications, Inc., Comcast Cable Communications Holdings, Inc), aligning with the announcer.
• The address inventory is finely subdivided into regional blocks, with netnames referencing specific markets like BAYAREA and SFBA, reflecting site-by-site segmentation of the corporate estate.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 23.24.192.0/19
• 24.4.0.0/15
• 24.6.0.0/16
• 24.7.0.0/17
• 24.104.72.0/23
• 24.104.138.0/23
• 24.104.150.0/24
• 24.124.158.0/23
• 24.130.0.0/16
• 50.76.32.0/19
• 50.78.96.0/20
• 50.79.32.0/20
• 50.79.208.0/21
• 50.145.55.0/24
• 50.176.128.0/19
• 50.189.64.0/18
• 50.191.160.0/19
• 50.193.0.0/18
• 50.196.128.0/18
• 50.197.128.0/18
• 50.200.170.0/24
• 50.201.8.0/23
• 50.201.171.0/24
• 50.204.119.0/24
• 50.204.137.0/24
• 50.205.226.0/24
• 50.206.118.0/24
• 50.206.120.0/23
• 50.206.219.0/24
• 50.207.182.0/24
• 50.207.190.0/24
• 50.207.216.0/24
• 50.208.32.0/19
• 50.209.128.0/18
• 50.211.192.0/19
• 50.213.0.0/18
• 50.215.0.0/19
• 50.216.23.0/24
• 50.216.212.0/24
• 50.218.46.0/24
• 50.219.139.0/24
• 50.222.26.0/24
• 50.222.50.0/24
• 50.222.102.0/24
• 50.224.7.0/24
• 50.227.120.0/24
• 50.227.186.0/24
• 50.228.130.0/24
• 50.229.212.0/24
• 50.230.66.0/24
• 50.231.143.0/24
• 50.232.196.0/24
• 50.233.45.0/24
• 50.234.130.0/24
• 50.235.20.0/23
• 50.235.233.0/24
• 50.236.66.0/24
• 50.239.184.0/24
• 50.240.192.0/19
• 50.242.64.0/18
• 50.247.64.0/18
• 50.250.192.0/18
• 50.254.128.0/19
• 50.255.0.0/18
• 64.84.96.0/21
• 64.84.120.0/21
• 67.160.192.0/18
• 67.161.0.0/18
• 67.161.64.0/20
• 67.164.0.0/17
• 67.169.0.0/17
• 67.169.128.0/18
• 67.170.192.0/18
• 67.174.192.0/18
• 67.180.0.0/16
• 67.188.0.0/16
• 68.85.28.0/24
• 68.85.57.0/24
• 68.85.86.0/24
• 68.85.100.0/22
• 68.85.154.0/23
• 68.85.190.0/23
• 68.85.216.0/23
• 68.86.62.0/24
• 68.86.142.0/23
• 68.86.248.0/23
• 68.87.76.0/24
• 68.87.192.0/21
• 68.87.226.0/23
• 68.87.251.0/24
• 68.87.252.0/24
• 69.91.146.0/24
• 69.139.198.0/23
• 69.181.0.0/16
• 69.241.74.0/23
• 69.241.90.0/24
• 69.252.70.0/24
• 69.252.96.0/23
• 69.252.197.0/24
• 69.252.255.0/24

and 261 more.

Upstream networks

• AS7922 Comcast Cable Communications, LLC
• AS3356 Level 3 Parent, LLC

Downstream networks

• AS1226 California Department of Technology
• AS46341 California Public Utilities Commission
• AS10309 County of Marin
• AS6379 A-Link Network Services, Inc.
• AS14203 Juniper Networks, Inc.
• AS25875 FriendFinder Networks Inc
• AS20066 Supermicro Computer
• AS22700 University of San Francisco
• AS46826 Razzo Link, Inc.
• AS16920 Wind River Systems, Inc.
• AS54113 Fastly, Inc.
• AS36040 Google LLC
• AS32537 Xilinx Incorporated
• AS32504 Intelletrace
• AS23154 Sanmina-SCI Corporation
• AS395976 Comcast Cable Communications, LLC
• AS63435 County of Monterey
• AS19126 KIZA
• AS11328 Bio-Rad Laboratories, Inc.
• AS46186 Gilead Sciences
• AS6099 Alameda County Office of Education
• AS55059 Microwave Power Products, Inc.
• AS35928 BECKMAN COULTER, INC.
• AS29878 Community Hospital of the Monterey Peninsula
• AS395011 City and County of San Francisco

Adjacent networks

• AS7922 Comcast Cable Communications, LLC
• AS1226 California Department of Technology
• AS3356 Level 3 Parent, LLC
• AS46341 California Public Utilities Commission
• AS10309 County of Marin
• AS6379 A-Link Network Services, Inc.
• AS14203 Juniper Networks, Inc.
• AS6099 Alameda County Office of Education
• AS25875 FriendFinder Networks Inc
• AS20066 Supermicro Computer
• AS22700 University of San Francisco
• AS46826 Razzo Link, Inc.
• AS16920 Wind River Systems, Inc.
• AS54113 Fastly, Inc.
• AS36040 Google LLC
• AS32537 Xilinx Incorporated
• AS32504 Intelletrace
• AS23154 Sanmina-SCI Corporation
• AS395976 Comcast Cable Communications, LLC
• AS63435 County of Monterey
• AS19126 KIZA
• AS11328 Bio-Rad Laboratories, Inc.
• AS46186 Gilead Sciences
• AS55059 Microwave Power Products, Inc.
• AS55064 Arista Networks, Inc.