1. A method associated with a source federate and with a destination federate both operable in an HLA computer simulation, wherein the source federate includes an HLA run-time infrastructure interface configured to communicate with the destination federate through an HLA physical layer, and wherein the destination federate includes an HLA run-time infrastructure interface configured to communicate with the source federate through the HLA physical layer, the method comprising: providing a first distributed communications effects module coupled between the source federate and the HLA physical layer, wherein the first distributed communications effects module comprises: an HLA run-time infrastructure interface configured to communicate with the source federate HLA run-time infrastructure through a physical layer that does not include the HLA physical layer; and an HLA run-time infrastructure interface configured to communicate through the HLA physical layer; receiving a simulated message from the source federate with the first distributed communications effects module; applying simulated communications effects to the simulated message with the first distributed communications effects module; and transmitting with the first distributed communications effects module, through the HLA physical layer, the simulated message with the applied simulated communications effects to a second different distributed communications effects module coupled between the destination federate and the HLA physical layer.