The Registration Data Access Protocol, or RDAP, replaces traditional port 43 Whois. It provides a number of enhancements relative to Whois，such as transport security, internationalization, a structured data format, differentiated access, and extensibility.
RDAP was designed by the weirds working group of the Internet Engineering Task Force (IETF)，as a result of a request by ICANN for the IETF to develop a replacement for Whois.
It is now maintained by the regext working group which is also responsible for EPP standards development.
2. 17EX's RDAP System
17EX's RDAP system has been implemented to comply with the following specifications:
RFC7480: HTTP Usage in the Registration Data Access Protocol (RDAP)
RFC7481: Security Services for the Registration Data Access Protocol (RDAP)
RFC7482: Registration Data Access Protocol (RDAP) Query Format
RFC7483: JSON Responses for the Registration Data Access Protocol (RDAP)
RFC7484: Finding the Authoritative Registration Data (RDAP) Service
RFC8056: Extensible Provisioning Protocol (EPP) and Registration Data Access Protocol (RDAP) Status Mapping
gTLD RDAP Implementation Guide (PDF)
gTLD RDAP Response Profile (PDF)
3. RDAP Infrastructure
The RDAP system runs on the same secure, resilient, high-performance infrastructure as the Whois system, and therefore enjoys the same reliability and scalability. It is available over both IPv4 and IPv6.
Like the Whois, the RDAP system uses a separate replica of the primary registry database and its own caching layer.
4. Rate Limiting
The RDAP system uses the same rate-limiting system as the Whois and follows the same policies. Note that this means that a port-43 whois counts against the RDAP query rate, and vice versa.
5. Security Controls
RDAP is only available over HTTPS, and 17EX's HTTPS configuration is compliant with all current operational best practices for TLS deployment.
6. Status of Port 43 Whois
Once RDAP has been deployed, ICANN no longer requires gTLD registries and registrars to provide a port 43 whois service. However,
in order to reduce disruption to users, 17EX will carry out a phased sunset plan to give users time to upgrade their systems to use RDAP.
We will provide more information about our plans to phase out the port 43 service in due course.
7. Comments and Questions
If you have any comments or questions about 17EX's RDAP system, please email email@example.com.