Embodiments herein provide a method, system, etc. for a sovereign
information sharing service. More specifically, a method for secure
distributed query processing comprises storing data tables from at least
one data provider in at least one first computer comprising a sovereign
server. Next, encrypted input and output of the data tables is performed
between the server and a second computer. Following this, join operations
are computed, comprising determining whether arbitrary join predicates
yield matches within the data tables; and encrypted results of the join
operations are output. The method minimizes possible information leakage
from interaction between the server and the second computer by making
observations and inferences from patterns of the outputting of the
encrypted results.