subnet.im

AS20214Comcast Cable Communications, LLC

United StatesRegistryARIN

As of 27th September 2026, AS20214 (Comcast Cable Communications, LLC), a network registered in the United States with ARIN, originates 22 IPv4 prefixes covering 141k addresses and 95 IPv6 prefixes. By IPv4 address space that makes it the 1,741st-largest of the 79,525 networks we see originating IPv4, and the 498th-largest of 18,428 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 24 downstream networks. 96% of its announcements have 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

22

IPv6 prefixes

95

IPv4 addresses

141k

IPv6 /64s

6.2M

Upstream graph

The networks AS20214 is seen behind, one and two hops out, drawn from real AS paths.

AS20214Toward the internet core
Upstream graph for AS20214: 5 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS20214Comcast 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 AS20214 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

52

adjacent networks

Upstreams
24%
Peers
2650%
Downstreams
2446%

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

Upstreams of AS20214
NetworkCountryRelationshipPathsVantage pts
AS7922Comcast Cable Communications, LLCUSPeer8,770145
AS3356Lumen (Level 3)USPeer57954

Prefixes

All 117

The largest blocks AS20214 originates, widest first.

Largest prefixes originated by AS20214
PrefixAddressesVisibility
147.137.0.0/1665.5k81/81
168.221.0.0/1665.5k81/81
168.221.176.0/204.1k81/81
50.205.246.0/2351280/81
50.233.138.0/2351280/81
50.150.146.0/2425679/81
50.200.25.0/2425680/81
50.200.159.0/2425680/81
50.202.4.0/2425680/81
50.202.167.0/2425680/81

Routing health

How AS20214'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

  • Valid95.7%112
  • Invalid0.0%0
  • No ROA4.3%5

Propagation

  • Globally propagated90% of full-feed peers or more100.0%117
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 22 prefixes

IPv6 — 95 prefixes

  • /4865.5k × /64100.0%95

Recent changes

Announcements that started or stopped since 28th Aug 2026.

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