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AS33661Comcast Cable Communications, LLC

United StatesRegistryARIN

As of 27th September 2026, AS33661 (Comcast Cable Communications, LLC), a network registered in the United States with ARIN, originates 6 IPv4 prefixes covering 1.5k addresses and 15 IPv6 prefixes. By IPv4 address space that makes it the 31,108th-largest of the 79,525 networks we see originating IPv4, and the 7,118th-largest of 18,428 in the United States. It is seen behind 1 upstream network, most often AS7922 (Comcast Cable Communications, LLC), and in front of 21 downstream networks. Every one of its announcements has a valid RPKI ROA, and none are RPKI-invalid. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

6

IPv6 prefixes

15

IPv4 addresses

1.5k

IPv6 /64s

983k

Upstream graph

The networks AS33661 is seen behind, one and two hops out, drawn from real AS paths.

AS33661Toward the internet core
Upstream graph for AS33661: 3 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS33661Comcast Cable Com…This networkAS7922Comcast Cable Com…AS1299Arelion (fka. Tel…AS2914NTT America, Inc.

Networks observed one and two hops upstream of AS33661 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

45

adjacent networks

Upstreams
12%
Peers
2351%
Downstreams
2147%

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

Upstreams of AS33661
NetworkCountryRelationshipPathsVantage pts
AS7922Comcast Cable Communications, LLCUSPeer4,274145

Prefixes

The largest blocks AS33661 originates, widest first.

Largest prefixes originated by AS33661
PrefixAddressesVisibility
50.218.97.0/2425681/81
50.220.33.0/2425681/81
50.226.0.0/2425681/81
50.227.97.0/2425681/81
50.236.155.0/2425681/81
50.237.76.0/2425681/81
2001:559:135::/4865.5k × /6464/64
2001:559:4ed::/4865.5k × /6464/64
2001:559:4ee::/4865.5k × /6464/64
2001:559:731::/4865.5k × /6464/64

Routing health

How AS33661'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

  • Valid100.0%21
  • Invalid0.0%0
  • No ROA0.0%0

Propagation

  • Globally propagated90% of full-feed peers or more100.0%21
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 6 prefixes

IPv6 — 15 prefixes

  • /4865.5k × /64100.0%15

Recent changes

Announcements that started or stopped since 28th Aug 2026.

  • Withdrawn50.228.116.0/2421st Sept 2026

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