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 v1.1.0 — a transparent heuristic, not a definitive verdict. How it works →
Network profile
Source: PeeringDB →Top CIDR ranges
| CIDR | IPs | PTR Density | Organization | Country | State | City |
|---|---|---|---|---|---|---|
| 128.220.0.0/16 | 65.5K |
5.7%
|
Johns Hopkins University | US | Maryland | Clarksville |
| 162.129.0.0/16 | 65.5K |
3.1%
|
Johns Hopkins University | US | Maryland | Baltimore |
| 198.57.32.0/21 | 2.0K |
0.0%
|
Johns Hopkins University | US | Florida | St. Petersburg |
| 198.57.40.0/22 | 1.0K |
10.4%
|
Johns Hopkins University | US | Florida | St. Petersburg |
| 204.124.184.0/22 | 1.0K |
0.0%
|
Johns Hopkins University | US | — | — |
| 192.12.13.0/24 | 256 |
1.2%
|
Johns Hopkins University | US | — | — |
| 192.12.14.0/24 | 256 |
0.0%
|
Johns Hopkins University | US | Maryland | Baltimore |
BGP Announced Prefixes
Live BGP anomalies →Prefixes AS5723 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 |
|---|---|---|
| 128.220.122.0/24 | 22,921 | 2026-06-15 08:05:28 |
| 198.57.40.0/22 | 16,811 | 2026-07-23 15:45:18 |
| 198.57.32.0/21 | 16,801 | 2026-07-23 15:45:18 |
| 128.220.0.0/16 | 13,089 | 2026-07-23 15:40:28 |
| 192.12.13.0/24 | 12,740 | 2026-07-23 15:40:28 |
| 192.12.14.0/24 | 12,732 | 2026-07-23 15:40:28 |
| 162.129.0.0/16 | 12,720 | 2026-07-23 15:40:28 |
| 198.57.39.0/24 | 12,524 | 2026-07-23 15:40:28 |
| 204.124.184.0/22 | 12,509 | 2026-07-23 15:40:28 |
| 128.220.222.0/24 | 4,287 | 2026-06-25 11:11:32 |
| 128.220.3.0/24 | 2,298 | 2026-07-05 23:41:19 |
| 162.129.251.0/24 | 2,114 | 2026-07-15 08:18:55 |
Frequently Asked Questions
What is AS5723?
AS5723 is an Autonomous System Number assigned to Johns Hopkins University. 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 AS5723 announce?
AS5723 announces 135.7K IPv4 addresses distributed across 7 routed CIDR prefixes. The network is registered in United States.
Who operates AS5723?
AS5723 is operated by Johns Hopkins University. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.
What country is AS5723 registered in?
AS5723 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.
