Enhancements to ARIN's RESTful Whois Now Available

Posted: Thu, 3 February 2011

ARIN deployed a series of enhancements to its Whois-RWS service on 3 February 2011.  ARIN has enabled CIDR support and IPv6 lookups in the search box on the web page, provided plain text rendering of lists of ASNs and networks on the web, and enhanced CIDR query matching on WHOIS port 43.

The first enhancement is CIDR matching capability on the search box for the web page. This allows you to search for a network address using prefix/length notation. Note that it will default to the less specific search result set that is described in the port 43 enhancements below.

The next enhancement is a change to the default output on a query initiated by the search box on the web page for IP addresses, organizations, and ASNs. The query for an IP address or network will return the network as well as the full output of related Organization and Point of Contact (POC) data for the network. Likewise, the query result for an AS number will output the associated organization and related POCs along with the AS number. The query result for an organization, will list all related networks and ASNs, and give full output of associated POCs. This will allow you to view all information on a single web page.  This “pft” option is an enhancement to the RESTful web interface, and it is not available on port 43. To use it, append “/pft” to the URL, for example:

  • http://whois.arin.net/rest/org/ARIN/pft
  • http://whois.arin.net/rest/net/ NET-192-136-136-0-1/pft

Note again that web search forms will default to using the “pft” option.

The NICNAME/WHOIS port 43 service now supports more than exact match CIDR. You can now use the following flags on CIDR queries:

  • The "=" will mean exact match.
  • The ">" will mean more specific or “down” the hierarchy.
  • The "<" will mean less specific or “up” the hierarchy.

If no hierarchy flag is given, "<" is to be assumed. The record type flag of “r” should be used for network address space queries by CIDR.

For full details on the Whois-RWS service, go to https://www.arin.net/resources/whoisrws/index.html

ARIN continues to welcome community participation on the Technical Discussions mailing list, and we invite you to subscribe and provide feedback to:


Mark Kosters
Chief Technology Officer
American Registry for Internet Numbers (ARIN)