The domain name system (DNS) is an essential component of the internet, allowing users to access websites using human-readable domain names instead of complex IP addresses. Behind every domain name is registration data that contains vital information about domain ownership and administrative contacts.
For decades, the WHOIS protocol served as the primary means of accessing domain registration data. However, WHOIS had significant limitations, including inconsistent data formats, security vulnerabilities, and a lack of access control. To address these challenges, the Internet Engineering Task Force (IETF) developed the Registration Data Access Protocol (RDAP) as a modern replacement for WHOIS.
In this article, we’ll explore what RDAP is, why it’s important, and how companies like HYAS Insight are leveraging it alongside exclusive infrastructure intelligence data to strengthen cybersecurity efforts.
RDAP was introduced by the IETF in 2015 (RFC 7480–7484) as a modern replacement for WHOIS. ICANN required all gTLD registries and registrars to implement RDAP by August 26, 2019. WHOIS was fully sunsetted on January 28, 2025, making RDAP the sole protocol for domain registration data access.
Unlike WHOIS, which delivers plain-text responses with little uniformity, RDAP uses a standardized RESTful API format, making it easier for systems and applications to integrate with domain registration data services.
RDAP offers several advantages over WHOIS, making it the preferred protocol for domain registration data access:
WHOIS lacks a consistent data structure, with different registries and registrars presenting data in varied formats. RDAP introduces uniform JSON-based responses, ensuring that data retrieval is consistent and machine-readable across all providers.
WHOIS allows unrestricted public access to domain registration data, which poses privacy and security risks. RDAP supports:
• Secure HTTPS connections to protect data integrity.
• Authentication mechanisms to control who can access specific data.
• Role-based access control, allowing registrars and registries to differentiate between public and restricted information.
With the growth of Internationalized Domain Names (IDNs), RDAP provides full Unicode support, making it easier to retrieve registration data for domains using non-Latin scripts, such as Arabic, Chinese, or Cyrillic.
RDAP enables tiered access, allowing registrars and registries to control who can access specific registration data. However, in practice, most WHOIS data remains redacted for privacy reasons, and access to additional data depends on individual registry and registrar policies.
To ensure a smooth transition from WHOIS, ICANN has mandated that all generic top-level domain (gTLD) registries and registrars implement RDAP. The deadline for RDAP implementation was August 26, 2019, after which all accredited registries and registrars were required to provide RDAP services in compliance with ICANN’s specifications.
ICANN also developed the gTLD RDAP Profile, which provides technical instructions for registries and registrars to ensure consistent implementation. This profile aligns with the Temporary Specification for gTLD Registration Data, ensuring compliance with GDPR and other data protection regulations.
The introduction of RDAP is a significant step forward in enhancing security, privacy, and transparency in domain registration data access. Here’s why RDAP matters:
Cybercriminals frequently exploit domain registration data for fraudulent activities, including phishing, malware distribution, and brand impersonation. RDAP enables cybersecurity professionals to access structured and authenticated registration data, aiding in threat intelligence and incident response.
The lack of access control in WHOIS made it easy for spammers and bad actors to harvest domain registration data for malicious purposes. With RDAP’s authentication and differentiated access features, sensitive domain ownership information can be protected from misuse.
Privacy laws like the General Data Protection Regulation (GDPR) necessitated changes in how domain registration data is accessed. RDAP ensures compliance with these regulations while still allowing legitimate stakeholders, such as law enforcement agencies and security firms, to obtain necessary domain information under proper authorization.
While RDAP significantly improves domain registration data access, cybersecurity firms need deeper intelligence to combat modern cyber threats effectively. This is where HYAS Insight comes in.
HYAS is the world’s premier provider of infrastructure intelligence, enabling organizations worldwide with unparalleled visibility, protection, and the necessary proactive intelligence to address cyber attacks, fraud, and all forms of digital risk. With real-time visibility into adversary infrastructure and their related devices, HYAS Insight allows security teams to track, monitor, and dismantle cyber threats and fraud with unmatched speed and precision.
Learn more at hyas.com
What sets HYAS Insight apart is its access to exclusive infrastructure intelligence data, which allows organizations to:
By leveraging proprietary data sources and advanced analytics, HYAS Insight goes beyond traditional domain intelligence, offering a more comprehensive view of internet-based threats.
As the cybersecurity landscape evolves, organizations must adopt tools that seamlessly integrate with modern data access protocols like RDAP. HYAS Insight proactively made the necessary adjustments to accommodate RDAP, ensuring that users:
With HYAS Insight, security teams don’t need to worry about managing RDAP compliance—the platform automatically integrates RDAP-enabled registration data into its intelligence framework, providing actionable insights without extra effort.
The Registration Data Access Protocol (RDAP) represents a significant improvement over WHOIS, offering enhanced security, structured data access, and compliance with global privacy laws. By implementing RDAP, the internet community is moving toward a more secure and efficient system for accessing domain registration data.
Meanwhile, HYAS Insight takes cybersecurity intelligence a step further by utilizing exclusive infrastructure intelligence data to identify, track, and mitigate cyber threats proactively. With built-in RDAP support, HYAS ensures that organizations can seamlessly access domain registration data without additional configuration or effort.
For businesses, cybersecurity professionals, and law enforcement agencies, leveraging RDAP-powered intelligence solutions like HYAS Insight is crucial in the fight against cybercrime. By staying ahead of the curve, organizations can detect threats earlier, prevent attacks, and enhance their overall security posture.