[5] In June 2012, the US Senate Armed Services Committee (SASC) released the Draft 2012 Department of Defense (DoD) Authorization Bill, which included references to Apache Accumulo.

[6] Specific criteria were not included in the draft language, but the establishment of commercial entities supporting Apache Accumulo could be considered a success factor.

[7] Apache Accumulo extends the Bigtable data model, adding a new element to the key called Column Visibility.

This element stores a logical combination of security labels that must be satisfied at query time in order for the key and value to be returned as part of a user request.

The range of operations that can be applied is equivalent to those that can be implemented within a MapReduce Combiner function, which produces an aggregate value for several key-value pairs.