Still referring to FIG. 1, it shall be noted that the recursive DNS server 110 can be associated with multiple caches 125. In certain embodiments, there can be provided one cache 125 per equivalence class. In yet more embodiments, each equivalence class may be associated with more than one cache.

In some embodiments, cache entries stored in the cache 125 can be tagged or labeled with a unique identifier associated to a corresponding equivalence class. For example, when an answer is stored in a cache, a unique identifier can be assigned to the answer to designate an equivalence class to which it belongs. Additionally, the tagging procedure can facilitate searching for cached answers associated with equivalence classes and improve operations of the recursive server 110. Moreover, in some example embodiments, the method disclosed herein can provide for provisioning membership of clients in equivalence classes.

According to yet additional embodiments of this disclosure, memberships in equivalence classes can be adjusted, tuned, or otherwise modified based upon one or more criteria or rules. The adjustment of memberships may be a necessary step in response to changing network conditions which periodically occur. Accordingly, a membership in one or more equivalence classes can be adjusted based on determining any changes in service (e.g., changes in bandwidth, quality of service, client location, and so forth). In yet additional embodiments, a membership in one or more equivalence classes can be adjusted based on detection of a modification to the network topology. In yet additional embodiments, a membership in one or more equivalence classes can be adjusted based on received input concerning performance of any suitable client subnet customized service.