subnet.im

AS33491Comcast Cable Communications, LLC

United StatesRegistryARIN

As of 27th September 2026, AS33491 (Comcast Cable Communications, LLC), a network registered in the United States with ARIN, originates 86 IPv4 prefixes covering 48.1k addresses and 203 IPv6 prefixes. By IPv4 address space that makes it the 4,552nd-largest of the 79,536 networks we see originating IPv4, and the 1,614th-largest of 18,430 in the United States. It is seen behind 2 upstream networks, most often AS7922 (Comcast Cable Communications, LLC) and AS3356 (Lumen (Level 3)), and in front of 256 downstream networks. 93% of its announcements have a valid RPKI ROA, and none are RPKI-invalid. 98% of its routes reach at least 90% of full-feed peers, and 7 prefixes are also originated by another network.

At a glance

IPv4 prefixes

86

IPv6 prefixes

203

IPv4 addresses

48.1k

IPv6 /64s

13.3M

Upstream graph

The networks AS33491 is seen behind, one and two hops out, drawn from real AS paths.

AS33491Toward the internet core
Upstream graph for AS33491: 5 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS33491Comcast Cable Com…This networkAS3356Lumen (Level 3)AS7922Comcast Cable Com…AS3549Lumen (fka. Globa…AS2914NTT America, Inc.AS1299Arelion (fka. Tel…

Networks observed one and two hops upstream of AS33491 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

518

adjacent networks

Upstreams
20%
Peers
26050%
Downstreams
25649%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS33491
NetworkCountryRelationshipPathsVantage pts
AS7922Comcast Cable Communications, LLCUSPeer34,277147
AS3356Lumen (Level 3)USPeer6,82361

Prefixes

All 289

The largest blocks AS33491 originates, widest first.

Largest prefixes originated by AS33491
PrefixAddressesVisibility
209.153.0.0/1816.4k82/82
164.68.64.0/204.1k82/82
164.68.80.0/212k82/82
50.220.4.0/221k81/82
50.229.76.0/221k81/82
164.68.88.0/221k82/82
50.205.54.0/2351281/82
50.220.130.0/2351281/82
50.224.140.0/2351281/82
107.0.96.0/2351281/82

Routing health

How AS33491's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid93.1%269
  • Invalid0.0%0
  • No ROA6.9%20

Propagation

  • Globally propagated90% of full-feed peers or more97.9%283
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%2.1%6

Prefix sizes

IPv4 — 86 prefixes

IPv6 — 203 prefixes

  • /4865.5k × /64100.0%203

Recent changes

Announcements that started or stopped since 28th Aug 2026.

  • Announced2001:559:1d6::/4825th Sept 2026
  • Withdrawn2001:559:1d6::/4825th Sept 2026
  • Announced2001:559:2d1::/4823rd Sept 2026
  • Withdrawn2001:559:2d1::/4822nd Sept 2026
  • Announced2001:559:3c2::/4822nd Sept 2026
  • Announced2001:559:813d::/4822nd Sept 2026
  • Announced2001:559:815d::/4822nd Sept 2026
  • Withdrawn107.0.182.0/2321st Sept 2026
  • Withdrawn2001:559:346::/4821st Sept 2026
  • Withdrawn2001:559:348::/4821st Sept 2026
  • Withdrawn2001:559:34a::/4821st Sept 2026
  • Withdrawn2001:559:8481::/4821st Sept 2026

5 announced and 9 withdrawn in all; the most recent are shown.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.