SAC053 | Executive Summary for SSAC Report on Dotless Domains

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This advisory addresses the frequently-asked question of whether a new generic top-level domain (gTLD) can be “dotless,” or consist of a single label without dots, such as “https://BRAND/”. The only completely unambiguous representation of a domain name is a “fully qualified domain name” (FQDN), in which (1) every label is explicitly included, (2) adjacent labels are separated from each other by a “dot” (period or full-stop symbol), and (3) the sequence of labels is terminated at the top level by a final dot, which represents the Domain Name System (DNS) root. An example of this is “www.icann.org.” 

Internet users often use domain names that are less than fully qualified (such as typing icann.org into a web browser), requiring that an application make assumptions about the user’s intent, and these assumptions may vary based on the application and/or context. Given current DNS implementation and existing application behavior, a dotless domain would not always work as expected and may pose a security threat due to its ambiguity. 

Recommendations

• Recommendation 1: Dotless domains will not be universally reachable and the SSAC recommends strongly against their use. As a result, the SSAC also recommends that the use of DNS resource records such as A, AAAA, and MX in the apex of a TLD be contractually prohibited where appropriate and strongly discouraged in all cases.