AS4991 Cogent Communications, LLC

COGENT-4991-4994 - Cogent Communications, LLC · registered in the United States

IPv4 addresses16,3841 prefixes · <0.001% of announced IPv4

Rank in United States#2,348largest network in US by IPv4 space, of 18,338 · <0.01% of US

Rank worldwide#6,987of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryUnited States18,679 ASNs registered there

Open AS4991 in ASN lookup Look up an IP in this network (204.6.192.1) All networks in United States

IPv4 prefixes

All 1 prefix, in address order.

204.6.192.0/18

Other ASNs named Cogent Communications, LLC

5 other networks use the same organisation name; together with AS4991 they announce 24,683,135 IPv4 addresses.

ASNNameIPv4 addresses

AS174COGENT-174 - Cogent Communications, LLC US24,663,935

AS1790COGENT-1790 - Cogent Communications, LLC US1,024

AS4550COGENT-4550 - Cogent Communications, LLC US1,024

AS1803COGENT-1803 - Cogent Communications, LLC US512

AS2149COGENT-2149 - Cogent Communications, LLC US256

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IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources