AS55
University of Pennsylvania
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 →
About University of Pennsylvania
The University of Pennsylvania is a private Ivy League research university in Philadelphia, Pennsylvania, United States. One of nine colonial colleges, it was chartered in 1755 through the efforts of founder and first president Benjamin Franklin, who advocated for an educational institution that trained leaders in academia, commerce, and public service.
Network profile
Source: PeeringDB →AS55 — global IP footprint
Cities where AS55 has measurable IPv4 allocation. Click any dot to open that city's page. Size and color scale with IP count.
Top CIDR ranges
| CIDR | IPs | PTR Density | Organization | Country | State | City |
|---|---|---|---|---|---|---|
| 128.91.0.0/16 | 65.5K |
48.7%
|
University of Pennsylvania | US | Pennsylvania | Philadelphia |
| 130.91.0.0/16 | 65.5K |
44.0%
|
University of Pennsylvania | US | Pennsylvania | Philadelphia |
| 158.130.0.0/16 | 65.5K |
13.3%
|
University of Pennsylvania | US | Pennsylvania | Philadelphia |
| 165.123.0.0/17 | 32.8K |
26.2%
|
University of Pennsylvania | US | Pennsylvania | Philadelphia |
| 165.123.128.0/18 | 16.4K |
47.8%
|
University of Pennsylvania | US | Pennsylvania | Philadelphia |
| 165.123.224.0/19 | 8.2K |
38.4%
|
University of Pennsylvania | US | Pennsylvania | Philadelphia |
| 165.123.208.0/20 | 4.1K |
6.7%
|
University of Pennsylvania | US | — | — |
| 165.123.200.0/21 | 2.0K |
0.0%
|
University of Pennsylvania | US | — | — |
| 165.123.196.0/22 | 1.0K |
0.0%
|
University of Pennsylvania | US | — | — |
| 165.123.194.0/23 | 512 |
0.0%
|
University of Pennsylvania | US | — | — |
| 192.84.2.0/24 | 256 |
36.7%
|
University of Pennsylvania | US | — | — |
BGP Announced Prefixes
Live BGP anomalies →Prefixes AS55 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 |
|---|---|---|
| 165.123.0.0/16 | 4,561 | 2026-07-23 15:08:19 |
| 158.130.0.0/16 | 4,554 | 2026-07-23 15:08:19 |
| 192.84.2.0/24 | 4,537 | 2026-07-23 15:08:19 |
| 128.91.0.0/16 | 4,530 | 2026-07-23 15:08:19 |
| 130.91.0.0/16 | 4,511 | 2026-07-23 15:08:19 |
Frequently Asked Questions
What is AS55?
AS55 is an Autonomous System Number assigned to University of Pennsylvania. 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 AS55 announce?
AS55 announces 261.9K IPv4 addresses distributed across 11 routed CIDR prefixes. The network is registered in United States.
Who operates AS55?
AS55 is operated by University of Pennsylvania. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.
What country is AS55 registered in?
AS55 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.
