Query domain information with RDAP
At Your Fingertips
RDAP provides structured information about domains. Besides practical command-line query tools, there are also libraries for integrating the protocol into your own programs.
Since the early days of the Internet and its division into different organizational areas, users have needed a way to obtain information about domains, the IP addresses they use, their owners, and a way of mapping them to each other. The WHOIS protocol was devised for this purpose in 1982 and introduced in RFC 812 [1]. The service can be accessed using a command-line tool of the same name, whois
. The age and importance of the protocol are evident from, among other things, its very low number – 43 – in the list of standardized ports for network services [2], which can be found in the file /etc/services
[3].
Thus far, this plain-text protocol has proven its value thanks to its simplicity, even if only request and response have been standardized in a fairly rough framework. The last update in RFC 3912 dates back to 2004 [4]. (See the "Regulations on WHOIS in Europe" box for details on that topic.) The search for a replacement has been underway for some time. The ideal candidate is the Registration Data Access Protocol (RDAP) [6], which is defined in more detail in RFC 9082 [7].
RDAP
The idea is for RDAP to completely replace WHOIS. It provides information about a domain via the HTTP protocol. This eliminates the need to open port 43 in the firewall. RDAP was standardized back in 2015 by an Internet Engineering Task Force (IETF) working group.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
So Long Neofetch and Thanks for the Info
Today is a day that every Linux user who enjoys bragging about their system(s) will mourn, as Neofetch has come to an end.
-
Ubuntu 24.04 Comes with a “Flaw"
If you're thinking you might want to upgrade from your current Ubuntu release to the latest, there's something you might want to consider before doing so.
-
Canonical Releases Ubuntu 24.04
After a brief pause because of the XZ vulnerability, Ubuntu 24.04 is now available for install.
-
Linux Servers Targeted by Akira Ransomware
A group of bad actors who have already extorted $42 million have their sights set on the Linux platform.
-
TUXEDO Computers Unveils Linux Laptop Featuring AMD Ryzen CPU
This latest release is the first laptop to include the new CPU from Ryzen and Linux preinstalled.
-
XZ Gets the All-Clear
The back door xz vulnerability has been officially reverted for Fedora 40 and versions 38 and 39 were never affected.
-
Canonical Collaborates with Qualcomm on New Venture
This new joint effort is geared toward bringing Ubuntu and Ubuntu Core to Qualcomm-powered devices.
-
Kodi 21.0 Open-Source Entertainment Hub Released
After a year of development, the award-winning Kodi cross-platform, media center software is now available with many new additions and improvements.
-
Linux Usage Increases in Two Key Areas
If market share is your thing, you'll be happy to know that Linux is on the rise in two areas that, if they keep climbing, could have serious meaning for Linux's future.
-
Vulnerability Discovered in xz Libraries
An urgent alert for Fedora 40 has been posted and users should pay attention.