I'll take it a step further and suggest that highly secure applications should be causality gapped - the system is only activated when more than 5 billion light

I'll take it a step further and suggest that highly secure applications should be causality gapped - the system is only activated when more than 5 billion light years from Earth, so no data could make it back before the sun destroys the planet. For critical applications, the system should be launched far enough from the edge of all observable matter, that it is causality gapped to the heat death of the universe.