AS21547
FirstLight Fiber, Inc.
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
- Multiple-origin (MOAS) routing anomaly −12
- Isp allocation +5
- Trust score 58 / 100
Experimental · trust-vectors model v1.2.0 — a transparent heuristic, not a definitive verdict. How it works →
⚠ 3 MOAS prefixes — multiple origin ASNs detected
All MOAS anomalies →A previously stable prefix originated by AS21547 is now also announced by another ASN (MOAS — Multiple-Origin AS), detected from our RIPE RIS collectors. Often benign (anycast, multi-homing, or a recent transfer) — but it can signal a route leak or prefix hijack, so it's worth inspecting.
| Prefix | Origin ASNs | Last detected (UTC) |
|---|---|---|
| 198.212.226.0/23 | AS21547, AS397779 | 2026-07-24 00:08:43 |
| 198.212.225.0/24 | AS21547, AS397779 | 2026-07-24 00:08:43 |
| 206.147.101.0/24 | AS21547, AS40160 | 2026-07-22 11:23:20 |
Network profile
Source: PeeringDB →AS21547 — global IP footprint
Cities where AS21547 has measurable IPv4 allocation. Click any dot to open that city's page. Size and color scale with IP count.
Top CIDR ranges
BGP Announced Prefixes
Live BGP anomalies →Prefixes AS21547 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 |
|---|---|---|
| 72.12.75.0/24 | 8,278 | 2026-07-24 00:03:51 |
| 66.186.176.0/24 | 7,975 | 2026-07-24 00:03:51 |
| 69.49.140.0/23 | 7,939 | 2026-07-24 00:03:51 |
| 66.231.192.0/24 | 7,926 | 2026-07-24 00:03:51 |
| 69.49.146.0/24 | 7,914 | 2026-07-24 00:03:51 |
| 140.165.50.0/24 | 7,011 | 2026-07-24 00:02:48 |
| 72.12.76.0/23 | 7,000 | 2026-07-24 00:03:25 |
| 72.12.80.0/24 | 6,953 | 2026-07-24 00:03:25 |
| 72.12.78.0/24 | 6,952 | 2026-07-24 00:03:25 |
| 72.12.79.0/24 | 6,946 | 2026-07-24 00:03:25 |
| 72.12.94.0/23 | 6,890 | 2026-07-24 00:03:25 |
| 72.12.92.0/24 | 6,890 | 2026-07-24 00:03:25 |
| 72.12.87.0/24 | 6,886 | 2026-07-24 00:03:25 |
| 72.12.84.0/24 | 6,878 | 2026-07-24 00:03:25 |
| 64.140.234.0/24 | 6,834 | 2026-07-24 00:03:26 |
| 198.212.230.0/24 | 6,810 | 2026-07-24 00:03:56 |
| 64.140.199.0/24 | 6,805 | 2026-07-24 00:03:26 |
| 66.186.171.0/24 | 6,802 | 2026-07-24 00:03:24 |
| 66.186.184.0/24 | 6,800 | 2026-07-24 00:03:25 |
| 66.186.188.0/24 | 6,779 | 2026-07-24 00:03:25 |
| 66.186.163.0/24 | 6,725 | 2026-07-24 00:03:25 |
| 66.186.162.0/24 | 6,713 | 2026-07-24 00:03:25 |
| 72.55.248.0/23 | 6,658 | 2026-07-24 00:03:26 |
| 72.55.254.0/23 | 6,652 | 2026-07-24 00:03:26 |
| 69.49.144.0/24 | 6,639 | 2026-07-24 00:03:25 |
| 69.49.148.0/24 | 6,637 | 2026-07-24 00:03:25 |
| 69.49.133.0/24 | 6,618 | 2026-07-24 00:03:56 |
| 74.220.236.0/24 | 6,599 | 2026-07-24 00:03:27 |
| 66.231.219.0/24 | 6,562 | 2026-07-24 00:03:24 |
| 66.231.207.0/24 | 6,548 | 2026-07-24 00:03:25 |
| 66.231.208.0/24 | 6,522 | 2026-07-24 00:03:25 |
| 66.231.214.0/24 | 6,505 | 2026-07-24 00:03:25 |
| 66.231.220.0/22 | 6,498 | 2026-07-24 00:03:24 |
| 66.231.215.0/24 | 6,495 | 2026-07-24 00:03:25 |
| 66.231.217.0/24 | 6,493 | 2026-07-24 00:03:24 |
| 69.49.128.0/24 | 6,419 | 2026-07-24 00:03:37 |
| 72.55.247.0/24 | 6,397 | 2026-07-24 00:03:37 |
| 69.49.129.0/24 | 6,381 | 2026-07-24 00:03:37 |
| 66.186.173.0/24 | 6,363 | 2026-07-24 00:03:36 |
| 72.12.91.0/24 | 5,900 | 2026-07-24 00:03:25 |
| 64.140.224.0/24 | 5,828 | 2026-07-24 00:03:26 |
| 64.140.225.0/24 | 5,827 | 2026-07-24 00:03:26 |
| 72.12.64.0/19 | 5,825 | 2026-07-24 00:03:25 |
| 64.140.224.0/19 | 5,824 | 2026-07-24 00:03:26 |
| 64.140.192.0/18 | 5,822 | 2026-07-24 00:03:26 |
| 64.140.246.0/24 | 5,807 | 2026-07-24 00:03:26 |
| 72.55.224.0/19 | 5,773 | 2026-07-24 00:03:26 |
| 74.220.224.0/20 | 5,728 | 2026-07-24 00:03:27 |
| 66.186.160.0/19 | 5,724 | 2026-07-24 00:03:25 |
| 69.49.128.0/19 | 5,713 | 2026-07-24 00:03:24 |
Showing top 50 of 70 announced prefixes by sample volume.
Frequently Asked Questions
What is AS21547?
AS21547 is an Autonomous System Number assigned to FirstLight Fiber, Inc.. 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 AS21547 announce?
AS21547 announces 68.4K IPv4 addresses distributed across 56 routed CIDR prefixes. The network is registered in United States.
Who operates AS21547?
AS21547 is operated by FirstLight Fiber, Inc.. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.
What country is AS21547 registered in?
AS21547 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.
