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WhoisXML API Blog

How to Find Out Who Owns a Domain Name with Reverse WHOIS Search and WHOIS Database Download

In the past, there was no way for users to find out what other domains, if any, a particular registrant owns without first translating a domain name into an IP address. But with the shortage of available IPv4 addresses, which resulted in the assignment of shared IP addresses to unrelated individuals or even companies, that approach has become riddled with difficulties.

Even if you can pinpoint the owner of an IP address, a shared one would provide users with a list of domains that may take a lot of time to sift through. If that IP address turns up as an indicator of compromise (IoC) in a publicly accessible report, affected users would have to go through each related domain’s WHOIS records to get to the bottom of the issue. Imagine how long that would take if you had 30 domains or more to scrutinize.

Thankfully, domain intelligence providers like our company have streamlined this process with the introduction of tools like Reverse WHOIS Search and offerings such as WHOIS Database Download.

This post shows how users can find out who owns a domain name in five simple steps.

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IP Netblocks WHOIS Database and IP Netblocks API: Two Relevant Ways to Search for LACNIC IP Block Owners

We recently announced that our IP netblocks services underwent data enrichment. Users of our database and API should be delighted to know that our ratio of IP netblocks from Latin America and the Caribbean with some meaningful contact information increased from 0% to 61%. Most of the entries previously showed redacted results, but that is no longer the case. We have substantially improved the ratio of IP netblocks with said information for other regions as well.

In light of this welcome development, we wrote this article for users looking for LACNIC netblock data for different purposes. The post includes some background on LACNIC and shows how to search for available IP blocks and effectively assess those they come into contact with by using our IP Netblocks WHOIS Database and IP Netblocks API.

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Email Validation API: 3 Reasons Why SaaS Business Managers Need One

The software-as-a-service (SaaS) industry has seen quite an expansion over the last years, with experts predicting that it will account for as much as 75% of all cloud workloads by 2021. The top reason for that is cost-effectiveness since cloud-based SaaS applications generally require less upfront investment and maintenance than on-premise software.

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4 Practical Usages of a Newly Registered & Just Expired Domains Database

Imagine a world without domain names. While it is possible to live in one, the majority of people would have a hard time memorizing sets of numbers instead of names. If you want to visit google[.]com, for example, you would need to type in 172[.]217[.]11[.]14 every single time – not to mention that this IP address might change every time Google changes the way it deploys its web server network. But you get the point. People would need to memorize several series of numbers so they can shop, pay bills, and get in touch with people from across the globe online.

We dare say that without domain names, the online world would not be flourishing as it is now. The domain name industry in itself is also thriving, with thousands of domains bought and registered every day. Verisign disclosed that during the fourth quarter of 2019, it closed 362.3 million domain name registrations across all top-level domains (TLDs).

With that enormous number, how can you monitor new domain names? That is where Newly Registered & Recently Expired Domains Data Feed comes in handy. But perhaps a more pressing question is why there should be a need to monitor domain names, notably, newly registered ones? We addressed these questions in this post, starting with the practical usages of having a newly registered domain list or database.

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Improving Managed Security Service Provision with a GeoIP Database

A data breach can have a lasting impact on an affected organization, with consequences ranging from reputation damage to loss of customer trust and staggering legal fines that result from lawsuits and settlement fees. Recent studies estimate the cost of a data breach caused by malicious attacks at $4.45 million. More than 70% of U.S. users also said that they’d avoid a company that does not sufficiently secure its data.

When it comes to securing your crown jewels and customer data, safeguarding all possible attack entry points should be a top priority. Organizations today must employ proactive and multilayered approaches to security that cover all their bases—endpoints, network, and data storage (whether in-house or cloud-based).

One way of ensuring sufficient protection is through a managed security service provider (MSSP) that uses a GeoIP database such as IP Geolocation Data Feed. This post offers some specific recommendations.

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4 App Development Challenges a WHOIS Data Lookup API Can Help Address

About 90% of the time people spend on their mobile devices is app use. And with almost half of the world’s 7.7 billion population using their phones and tablets every day, the app development market is indeed a financially rewarding sector. In fact, experts predict the overall market’s revenue to reach $407 billion by 2026.

But like any other booming market, the app development sector has several hurdles to overcome. What immediately comes to mind is the challenge of creating an app with minimal bugs and glitches. Then, there is also the issue of marketability. How do you make sure it gets downloaded and used by the people you created them for?

A WHOIS data lookup API may be able to help. We specifically explored four app development challenges where WHOIS API can make a difference.

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Why DNS History Matters: 5 Key Use Cases of Passive DNS

When Florian Weimer introduced the passive Domain Name System (DNS) replication technology in 2005, his goal was to provide a source of name resolution data distilled from actual DNS query traffic. He also saw the necessity to find a way to look at DNS history as a safeguard against the ease with which anyone can control and modify DNS records.

Where did things go from there? Passive DNS has been around for a decade and a half, but there is still confusion as to what it is and how it can help organizations. So, this article aims to distinguish passive from active DNS. By extension, we explored some reasons why a passive DNS database that gives users access to DNS history can be very beneficial.

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Early Typosquatting Detection Made Possible: A Short Illustration in the Financial Sector

On March 12, 2020, IBM X-Force Exchange published an early warning on a Wells Fargo Squatting Campaign:

“We observed 3 Squatting Domain registrations related to a victim in the finance and insurance sector. The campaign was identified starting with the registration on 2020-03-07 01:15:57 up to the latest registration on 2020-03-12 11:13:30.

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