Yeah, VoltDB&#x27;s not free for many purposes; neither is it Ellison expensive. Factor that into your decision. But at least the costs are up front.<p>In both the VoltDB case, and the Kakfa&#x2F;Storm&#x2F;Cassandra case, licensing is probably not the biggest TCO driver, whether you pay Confluent&#x2F;DataStax or not.<p>The Right Questions:<p>Which solution gets you to production faster?<p>Which requires less engineering to get running?<p>Which solution is more robust?<p>Which solution is easier to manage?<p>What is the quality of the insight from the solution?<p>And yes, totally, what are the licensing costs?