Reputation · trust score
A transparent 0–100 signal. Every entity starts at a neutral baseline of 65; threat-intel blocklists, exposure, reverse-DNS, routing and allocation each adjust it up or down. Higher is more trustworthy.
- Baseline (neutral) 65
- Isp allocation +5
- Trust score 70 / 100
Experimental · trust-vectors model v1.1.0 — a transparent heuristic, not a definitive verdict. How it works →
About Cogent Communications
Cogent Communications Holdings, Inc. is a multinational internet service provider based in the United States.
Top CIDR ranges
| CIDR | IPs | PTR Density | Organization | Country | State | City |
|---|---|---|---|---|---|---|
| 204.6.192.0/18 | 16.4K |
0.0%
|
Cogent Communications, LLC | US | — | — |
BGP Announced Prefixes
Live BGP anomalies →Prefixes AS4991 actually originates in BGP, observed across our RIPE RIS collectors. This live routing view can differ from the registry allocation above.
| Prefix | Announcement samples | Last seen |
|---|---|---|
| 204.6.192.0/18 | 8,144 | 2026-07-18 12:18:44 |
Frequently Asked Questions
What is AS4991?
AS4991 is an Autonomous System Number assigned to Cogent Communications, LLC. An ASN identifies a network that controls a specific set of IP addresses and determines how traffic is routed across the internet via BGP (Border Gateway Protocol).
How many IP addresses does AS4991 announce?
AS4991 announces 16.4K IPv4 addresses distributed across 1 routed CIDR prefixes. The network is registered in United States.
Who operates AS4991?
AS4991 is operated by Cogent Communications, LLC. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.
What country is AS4991 registered in?
AS4991 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.
