How to Detect VPNs, Data Centers, and Suspicious Traffic Using ASN Data

IPRout Team — Thu, 11 Jun 2026 09:17:29 +0000

How to Detect VPNs, Data Centers, and Suspicious Traffic Using ASN Data

Most developers think about IP intelligence in terms of geolocation.

Questions like:

Which country is this user from?
Which city are they connecting from?
What language should I show?

are common.

But after working with APIs, analytics, and security systems, I've found that ASN data is often more useful than country data.

If you're building authentication systems, fraud detection, analytics platforms, or API security controls, ASN information can provide context that geolocation alone cannot.

What Is an ASN?

ASN stands for Autonomous System Number.

Every major ISP, cloud provider, mobile carrier, and network operator on the internet is assigned one or more ASNs.

Examples include:

Google
Amazon AWS
Microsoft Azure
Cloudflare
Telstra
Comcast

Why ASN Data Matters

Imagine a user signs up from an IP address located in Australia.

Traditional GeoIP data might tell you the country and city.

But ASN data might tell you the traffic originates from Amazon AWS rather than a residential internet connection.

That additional context can be extremely valuable.

Detecting Data Center Traffic

Many bots, scrapers, and automated systems operate from cloud providers.

Common examples:

AWS
Azure
Google Cloud
DigitalOcean
Vultr
Oracle Cloud

If your application receives large volumes of registrations or API requests from these providers, ASN data can help identify patterns.

This doesn't automatically mean the traffic is malicious.

But it does provide another signal that can be combined with:

Rate limits
Device fingerprints
User behavior
Reputation systems

Detecting VPN Usage

Many VPN providers operate infrastructure from hosting providers and data centers.

While ASN data alone cannot definitively identify every VPN user, it can help detect traffic that originates from networks commonly associated with VPN infrastructure.

Fraud Prevention

ASN data is particularly useful during:

User registration
Account recovery
Login verification
Payment processing

ASN is not a final decision-maker.

It's another signal that helps build a risk profile.

Analytics and Reporting

ASN information can also improve visibility into your user base.

Questions you can answer include:

How much traffic comes from mobile carriers?
How much traffic comes from cloud providers?
Which ISPs are most common?
Which networks generate the most abuse reports?

Example Lookup

A simple ASN lookup can provide:

Geographic location
Network owner
ASN information

Final Thoughts

Country-level geolocation is useful.

ASN intelligence often provides the context that makes that geolocation meaningful.

If you're building authentication systems, fraud detection tools, analytics platforms, or API security controls, then ASN data is worth paying attention to.

Example lookups in this article were performed using IPRout, a developer-first GeoIP and ASN API currently in public beta.

Website: https://iprout.com

I Built a Developer-First GeoIP & ASN API Because Most Projects Don’t Need the Complexity

IPRout Team — Tue, 02 Jun 2026 07:49:33 +0000

Why I Built Yet Another GeoIP API

TL;DR: I built IPRout, a developer-first GeoIP and ASN API focused on simplicity, fast onboarding, and free developer access. I'm looking for feedback from other developers building products that rely on IP intelligence.

Most applications only need a few pieces of IP intelligence:

Country
ASN
ISP / Organization
Basic geolocation

Yet many solutions felt overly complex, expensive, or required account creation before you could even test them.

While integrating GeoIP services into several projects, a recurring pattern emerged: developers often needed only a small subset of data but were forced into much larger products and pricing structures.

That led to building IPRout, a developer-first GeoIP and ASN API focused on simplicity and fast onboarding.

The Problem

GeoIP data appears in more applications than most people realize.

Common use cases include:

Fraud prevention
User analytics
Content localization
Security monitoring
API protection
Compliance requirements

In many cases, developers simply need answers to a few straightforward questions:

Which country is this IP from?
Which organization owns this IP?
Which ASN is associated with this address?
Is the traffic coming from a residential ISP or a cloud provider?

For those scenarios, getting started should be simple.

What is IPRout?

IPRout is a GeoIP and ASN lookup API designed with developers in mind.

The goal was straightforward:

Fast API responses
Simple onboarding
Developer-friendly access
No unnecessary complexity

A lookup is as simple as:

curl https://api.iprout.com/ip/8.8.8.8

Example response:

{
  "ip": "8.8.8.8",
  "country": "US",
  "country_name": "United States",
  "asn": 15169,
  "organization": "Google LLC"
}

Free Developer Access

One thing that has always been frustrating as a developer is having to create an account, verify an email address, and sometimes even provide payment details before being able to test an API.

To reduce that friction, IPRout provides a:

7-Day Developer Key

No login required
CAPTCHA protected
1,000 requests over 7 days
Immediate access for testing

Free Account

10,000 requests per month
API key management
Usage dashboard

The goal is simple: let developers try the API properly before deciding whether it fits their project.

Common Use Cases

User Localization

Determine a visitor's country and adapt content or experiences accordingly.

Analytics

Understand where traffic originates and which networks your users connect from.

Security

Identify requests originating from cloud providers, hosting networks, or unexpected regions.

Fraud Prevention

Combine country and ASN information with existing risk signals during signups, authentication, and payment workflows.

API Access Controls

Restrict, allow, or monitor traffic based on geographic location or network ownership.

Built for Simplicity

There are already excellent IP intelligence providers available.

The goal of IPRout is not to replace every enterprise-grade platform.

The goal is to provide a straightforward API for developers who need reliable GeoIP and ASN data without unnecessary complexity.

Sometimes the best developer experience is simply making common things easy.

Looking for Feedback

IPRout is currently in public beta and I'd love feedback from fellow developers.

A few questions I'm particularly interested in:

What GeoIP fields do you actually use in production?
What information do you wish providers exposed more clearly?
What integrations would be useful?
What does a good developer experience look like for this type of API?

Every feature currently planned is being driven by developer feedback.

If you'd like to try it out or share feedback, I'd love to hear your thoughts.

Website: https://iprout.com

Happy building.

DEV Community: IPRout Team

How to Detect VPNs, Data Centers, and Suspicious Traffic Using ASN Data

How to Detect VPNs, Data Centers, and Suspicious Traffic Using ASN Data

What Is an ASN?

Why ASN Data Matters

Detecting Data Center Traffic

Detecting VPN Usage

Fraud Prevention

Analytics and Reporting

Example Lookup

Final Thoughts

I Built a Developer-First GeoIP & ASN API Because Most Projects Don’t Need the Complexity

Why I Built Yet Another GeoIP API

The Problem

What is IPRout?

Free Developer Access

7-Day Developer Key

Free Account

Common Use Cases

User Localization

Analytics

Security

Fraud Prevention

API Access Controls

Built for Simplicity

Looking for Feedback