+
+ /* Calculate RTT and bandwidth.
+ The RTT is the time between the MTU probe burst was sent and the first
+ reply is received. The bandwidth is measured using the time between the
+ arrival of the first and third probe reply.
+ */
+
+ struct timeval now, diff;
+ gettimeofday(&now, NULL);
+ timersub(&now, &n->probe_time, &diff);
+ n->probe_counter++;
+
+ if(n->probe_counter == 1) {
+ n->rtt = diff.tv_sec + diff.tv_usec * 1e-6;
+ n->probe_time = now;
+ } else if(n->probe_counter == 3) {
+ n->bandwidth = 2.0 * len / (diff.tv_sec + diff.tv_usec * 1e-6);
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "%s (%s) RTT %.2f ms, burst bandwidth %.3f Mbit/s, rx packet loss %.2f %%", n->name, n->hostname, n->rtt * 1e3, n->bandwidth * 8e-6, n->packetloss * 1e2);
+ }