14. A processing system for prepending nonce labels to DNS queries the system, comprising: at least one processor; and a nonce label analyzer module associated with the at least one processor, the nonce label analyzer module being configured: to evaluate whether a log contains at least one nonce label prepended domain name resolution query for a full domain name that resulted in a non-referral response, upon determination that a predetermined time duration has expired, to determine whether the log contains a nonce-less domain name resolution query for the full domain name, and to flag the full domain name as being exempt from nonce label prepending, upon determination that the log contains the nonce-less domain name resolution query.
14. A processing system for prepending nonce labels to DNS queries the system, comprising: at least one processor; and a nonce label analyzer module associated with the at least one processor, the nonce label analyzer module being configured: to evaluate whether a log contains at least one nonce label prepended domain name resolution query for a full domain name that resulted in a non-referral response, upon determination that a predetermined time duration has expired, to determine whether the log contains a nonce-less domain name resolution query for the full domain name, and to flag the full domain name as being exempt from nonce label prepending, upon determination that the log contains the nonce-less domain name resolution query. 15. The processing system of claim 14 , further comprising a DNS resolver coupled to the at least one processor and being configured to attempt domain name resolution with a nonce-less query when a previous domain name resolution attempt using a nonce-prepended query has failed.