A hash key is generated based on an information object and a lookup operation is performed in a hash table based on the hash key. A determination is made whether an entry in the hash table at an index corresponding to the hash key identifies a labelset for the information object. A labelset, identifying a sensitivity of the information object, is stored in the entry at the index corresponding to the hash key for the information object if a labelset for the information object is not identified in the entry in the hash table. Information flows involving the information object are authorized based on a lookup of the labelset associated with the information object in the hash table. The hash table may be a multidimensional hash table.