d-64bit NL
      word-64bit    = 6(otp-word 1*LWSP-char)
      otp-word      = &lt;any valid word in the standard OTP coding
                      dictionary&gt;

   Examples of these responses are:

      hex:8720 33d4 6202 9172
      word:VAST SAUL TAKE SODA SUCH BOLT

3.2. Requirements

   A server compliant with this specification:

      1. MUST process all arguments in a case-insensitive manner

   A generator compliant with this specification:

      1. SHOULD generate otp-word tokens in upper case w