AS104
University of Colorado at Boulder
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
- Academic allocation +6
- Trust score 71 / 100
Experimental · trust-vectors model v1.2.0 — a transparent heuristic, not a definitive verdict. How it works →
About University of Colorado Boulder
The University of Colorado Boulder is a public research university in Boulder, Colorado, United States. Founded in 1876, five months before Colorado became a state, it is the flagship university of the University of Colorado system.
Network profile
Source: PeeringDB →Top CIDR ranges
BGP Announced Prefixes
Live BGP anomalies →Prefixes AS104 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 |
|---|---|---|
| 129.19.192.0/18 | 29,462 | 2026-09-12 17:39:39 |
| 128.138.0.0/16 | 26,156 | 2026-09-12 17:39:39 |
| 146.5.20.0/22 | 26,027 | 2026-09-12 17:39:39 |
| 192.12.238.0/24 | 25,999 | 2026-09-12 17:39:28 |
| 192.12.242.0/24 | 24,436 | 2026-09-12 17:39:28 |
| 192.12.240.0/24 | 24,426 | 2026-09-12 17:39:28 |
| 192.12.245.0/24 | 24,415 | 2026-09-12 17:39:28 |
| 198.59.70.0/24 | 24,380 | 2026-09-12 17:39:28 |
| 198.59.51.0/24 | 24,302 | 2026-09-12 17:39:28 |
| 198.59.81.0/24 | 24,292 | 2026-09-12 17:39:28 |
| 192.12.241.0/24 | 24,287 | 2026-09-12 17:39:28 |
| 198.11.16.0/20 | 24,281 | 2026-09-12 17:39:28 |
| 198.59.82.0/24 | 24,272 | 2026-09-12 17:39:28 |
| 198.59.55.0/24 | 24,233 | 2026-09-12 17:39:28 |
| 192.12.244.0/24 | 24,227 | 2026-09-12 17:39:28 |
| 198.59.7.0/24 | 24,148 | 2026-09-12 17:39:28 |
| 198.59.52.0/24 | 24,112 | 2026-09-12 17:39:28 |
| 198.59.83.0/24 | 24,085 | 2026-09-12 17:39:28 |
| 198.59.54.0/24 | 24,038 | 2026-09-12 17:39:28 |
| 204.228.80.0/24 | 16,630 | 2026-09-12 17:38:39 |
| 129.19.240.0/20 | 6,572 | 2026-09-12 17:39:32 |
| 129.19.192.0/20 | 26 | 2026-08-17 17:48:21 |
Frequently Asked Questions
What is AS104?
AS104 is an Autonomous System Number assigned to University of Colorado at Boulder. 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 AS104 announce?
AS104 announces 91.1K IPv4 addresses distributed across 16 routed CIDR prefixes. The network is registered in United States.
Who operates AS104?
AS104 is operated by University of Colorado at Boulder. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.
What country is AS104 registered in?
AS104 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.
