In many ways, the RDAP has turned out to be an improved version of Whois. The IEFT working group has concentrated on the old protocol’s weaknesses, meaning that it has focused heavily on the likes of security, structuring, and internationalization for the new query protocol. As a result, several new features emerged, including:
- Structured request and answer semantics (including standardized error messages)
- Secure access to the requested contact details (e.g. via HTTPS)
- Expandability (e.g. addition of output elements)
- ‘Bootstrapping’ mechanism (supported by the search for a suitable authoritative DNS server)
- Web-based (HTTP) and REST compliant
- Uncomplicated translation of output data
- Possibility of granting differentiated access to contact details
In many aspects, the Registration Data Access Protocol has proven itself to be much more flexible than its predecessor. While Whois, as a text-based protocol is linked to TCP and the specific port (43), RDAP uses the web standard HTTP, or even HTTPS. This means that all data is delivered in a standardized, machine-readable JSON format. This means that on the one hand, the RDAP allows for more freedom when it comes to data queries, while also making it easier to program query services that can communicate with the various registration authorities, while outputting the requested data in different languages.