1. A method of simulating a network comprising: determining transmission events at a first node of the network, determining a plurality of reception events at other nodes of the network corresponding to each of the transmission event, and simulating the reception events at the other nodes; wherein: at least one of the transmission events includes an explicit-traffic packet, and at least another of the transmission events includes a tracer packet that represents a plurality of background-traffic packets, and simulating the reception events at the other nodes includes determining an effect of the background-traffic packets on the explicit-traffic packet.