AS174

AS174 is the backbone of Cogent Communications, a major Tier-1 transit provider registered to Cogent Communications, LLC under ARIN and active since May 1996. Cogent is known for high-capacity, low-cost transit and for serving business broadband in office buildings, and AS174 carries that traffic across one of the largest customer cones on the Internet. CAIDA AS Rank places it #4 globally, with a customer cone of roughly 41,127 ASNs, ~806,764 prefixes, and ~1.6 billion addresses, a transit degree near 6,656, and thousands of direct customers. The most analyst-relevant trait is reputational rather than security-based: Cogent has been involved in more peering disputes than any other Tier-1, and these disputes routinely cause reachability and latency anomalies. Documented examples include the long-running IPv6 peering dispute with Hurricane Electric, an IPv6 dispute with Google, a 2024 de-peering with NTT (AS2914) that spiked latency for single-homed European customers on both sides, and a 2024 withdrawal of peering with Tata (AS6453). As a backbone, abuse signals attach to downstream customers, not to AS174.

Operator

Cogent Communications, LLC (ARIN OrgId COGC) [Confirmed] — ARIN RDAP/WHOIS

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP

Allocated

1996-05-16 [Confirmed] — ARIN RDAP

Org status

active; notable peering disputes — IPv6 with Hurricane Electric, IPv6 with Google, 2024 de-peering with NTT (AS2914), 2024 withdrawal of peering with Tata (AS6453) — bgp.tools, theregister.com, en.wikipedia.org/wiki/Cogent_Communications

Security/abuse context

transit backbone; abuse attaches to downstream customers. Community notes occasional congestion/packet-loss complaints; no notable standalone abuse designation as of 2026-06-03

Network & routing

Network type

transit-backbone (Tier-1) + business broadband [Confirmed] — CAIDA + bgp.tools

Size

CAIDA AS Rank #4 globally — customer cone ~41,127 ASNs / ~806,764 prefixes / ~1,600,914,840 addresses; transit degree ~6,656; ~6,560 customers, ~101 peers; ~3,850 IPv4 + ~429 IPv6 prefixes originated — asrank.caida.org/asns/174, bgp.tools (2026-05)

Routing/peering

selective/restrictive; RPKI validating ROV — bgp.tools

Notable usage

major low-cost Tier-1 transit + business broadband — cogentco.com

Related ASNs

disputes/relationships with AS2914 (NTT), AS6453 (Tata), AS6939 (Hurricane Electric)

Analyst note

Seen mid-path as transit. Cogent's peering disputes can explain otherwise-puzzling reachability/latency anomalies (e.g., EU↔EU traffic routed via the US).