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 v1.1.0 — a transparent heuristic, not a definitive verdict. How it works →
About Level 3 Communications
Level 3 Communications, Inc. was an American multinational telecommunications and internet service provider company headquartered in Broomfield, Colorado.
⚠ 20 MOAS prefixes — multiple origin ASNs detected
All MOAS anomalies →A previously stable prefix originated by AS203 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) |
|---|---|---|
| 204.75.143.0/24 | AS203, AS1428 | 2026-07-18 11:37:44 |
| 205.140.226.0/24 | AS203, AS3356 | 2026-07-18 11:37:44 |
| 170.46.132.0/23 | AS203, AS18697 | 2026-07-18 11:37:44 |
| 170.46.162.0/24 | AS203, AS18697 | 2026-07-18 11:37:44 |
| 170.46.0.0/16 | AS203, AS18697 | 2026-07-18 11:37:44 |
| 170.46.200.0/24 | AS203, AS18697 | 2026-07-18 11:37:44 |
| 205.166.171.0/24 | AS203, AS26845 | 2026-07-18 11:37:44 |
| 143.199.145.0/24 | AS203, AS21680 | 2026-07-18 11:37:44 |
| 66.193.107.0/24 | AS203, AS22509 | 2026-07-18 11:37:44 |
| 143.199.96.0/24 | AS203, AS21680 | 2026-07-18 08:52:43 |
| 63.106.6.0/24 | AS203, AS22587 | 2026-07-17 23:07:39 |
| 63.144.218.0/24 | AS203, AS22587 | 2026-07-17 19:22:38 |
| 63.150.74.0/23 | AS203, AS22587 | 2026-07-17 19:22:38 |
| 50.58.252.0/24 | AS203, AS26845 | 2026-07-17 19:22:38 |
| 65.240.184.0/23 | AS203, AS22587 | 2026-07-17 19:22:38 |
Showing the 15 most recently detected of 20 MOAS prefixes. Many multi-origin prefixes on large networks are benign (anycast); see all MOAS anomalies.
Top CIDR ranges
BGP Announced Prefixes
Live BGP anomalies →Prefixes AS203 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 |
|---|---|---|
| 204.146.159.0/24 | 7,552 | 2026-07-18 10:48:48 |
| 143.199.28.0/24 | 5,976 | 2026-07-18 10:52:00 |
| 143.199.135.0/24 | 5,975 | 2026-07-18 10:52:00 |
| 143.199.222.0/24 | 5,961 | 2026-07-18 10:52:00 |
| 143.199.109.0/24 | 5,956 | 2026-07-18 10:52:00 |
| 8.41.218.0/24 | 5,931 | 2026-05-31 02:33:00 |
| 148.59.168.0/24 | 5,861 | 2026-07-18 10:52:00 |
| 161.7.38.0/24 | 5,378 | 2026-06-04 15:43:25 |
| 161.7.129.0/24 | 5,347 | 2026-06-04 15:43:25 |
| 143.199.140.0/23 | 5,269 | 2026-07-18 10:52:00 |
| 143.199.96.0/24 | 5,265 | 2026-07-18 10:52:00 |
| 143.199.145.0/24 | 4,653 | 2026-07-18 10:52:00 |
| 8.18.63.0/24 | 4,431 | 2026-07-18 10:52:03 |
| 165.193.54.0/23 | 4,309 | 2026-06-03 22:36:21 |
| 205.139.32.0/23 | 4,295 | 2026-06-03 22:36:21 |
| 8.44.205.0/24 | 4,242 | 2026-07-18 10:52:03 |
| 8.20.69.0/24 | 4,116 | 2026-07-18 10:51:58 |
| 8.25.26.0/24 | 4,101 | 2026-07-18 10:51:58 |
| 212.26.53.0/24 | 4,092 | 2026-07-13 06:46:21 |
| 8.15.229.0/24 | 3,957 | 2026-07-18 10:51:58 |
| 189.125.51.0/24 | 3,956 | 2026-07-18 10:52:33 |
| 8.7.155.0/24 | 3,816 | 2026-07-18 10:51:58 |
| 50.58.252.0/24 | 3,761 | 2026-07-18 10:52:00 |
| 205.166.171.0/24 | 3,733 | 2026-07-18 10:52:00 |
| 38.107.240.0/24 | 3,487 | 2026-07-18 10:51:58 |
| 62.67.222.0/24 | 3,400 | 2026-07-18 10:51:58 |
| 64.241.121.0/24 | 3,319 | 2026-07-18 10:51:58 |
| 216.114.73.0/24 | 3,304 | 2026-07-18 10:48:48 |
| 64.241.120.0/24 | 3,287 | 2026-07-18 10:51:58 |
| 63.128.14.0/24 | 3,258 | 2026-07-18 10:51:58 |
| 63.128.1.0/24 | 3,258 | 2026-07-18 10:51:58 |
| 64.208.127.0/24 | 3,256 | 2026-07-18 10:51:58 |
| 63.128.24.0/24 | 3,255 | 2026-07-18 10:51:58 |
| 63.128.0.0/22 | 3,253 | 2026-07-18 10:51:58 |
| 63.128.12.0/24 | 3,248 | 2026-07-18 10:51:58 |
| 128.177.179.0/24 | 3,246 | 2026-07-18 10:51:58 |
| 63.128.7.0/24 | 3,244 | 2026-07-18 10:51:58 |
| 161.209.96.0/20 | 3,241 | 2026-07-18 10:51:58 |
| 156.42.224.0/19 | 3,239 | 2026-07-18 10:51:58 |
| 64.209.141.0/24 | 3,238 | 2026-07-18 10:51:58 |
| 64.22.148.0/24 | 3,236 | 2026-07-18 10:51:58 |
| 63.128.8.0/22 | 3,235 | 2026-07-18 10:51:58 |
| 63.128.20.0/24 | 3,234 | 2026-07-18 10:51:58 |
| 161.209.100.0/24 | 3,233 | 2026-07-18 10:51:58 |
| 161.209.225.0/24 | 3,225 | 2026-07-18 10:51:58 |
| 161.209.192.0/19 | 3,220 | 2026-07-18 10:51:58 |
| 156.42.64.0/19 | 3,215 | 2026-07-18 10:51:58 |
| 170.22.90.0/24 | 3,215 | 2026-07-18 10:51:58 |
| 156.42.160.0/19 | 3,212 | 2026-07-18 10:51:58 |
| 161.209.97.0/24 | 3,211 | 2026-07-18 10:51:58 |
Showing top 50 of 204 announced prefixes by sample volume.
Frequently Asked Questions
What is AS203?
AS203 is an Autonomous System Number assigned to Level 3 Parent, 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 AS203 announce?
AS203 announces 171.5K IPv4 addresses distributed across 73 routed CIDR prefixes. The network is registered in United States.
Who operates AS203?
AS203 is operated by Level 3 Parent, LLC. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.
What country is AS203 registered in?
AS203 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.
