As Allocator reported, JSTARS has a system to prevent code duplication in its log, due to its log engine that sometime could be "joked" by not constant data/callsign transmission from traffic. It depends from many variables, like distance from traffic and your antenna, traffic is not transmitting always its callsign, crew/on board computer sets/changes often their callsign, this means that on port 30003 will arrive many ID/AIR data rows that would be logged.... to avoid it, I added a timer based on my experimental tests and I found good a time of 4 minutes, usually is the best choice.