Replay Rate Trace Experiment
In a dynamic network, at least one network parameter changes over time. In the replay rate trace experiment, a scheduled link transmits packets according to a trace file that specifies the packet departure times. This approach is adopted from the Mahimahi tool that implements such replay links named LinkShell. The scheduled link results in a time-variant bandwidth and round-trip time (RTT).
Scenario
In the random walk experiment, a single flow operates in a dynamic
dumbbell network. The flow generates greedy source traffic and uses a
CCA. The bottleneck link of the dumbbell network is set up as the
scheduled link, whose transmissions occur according to a trace file. The
trace file can bet set with the parameter trace_file.
To summarize the experiment setup:
Topology: Dumbbell topology (\(K=1\)) with at least one dynamic network parameter
Flows: A single flow (\(K=1\)) that uses a CCA
Traffic Generation Model: Greedy source traffic
Experiment Results
Experiment #79
Parameters
Command: ns3-dev-ccperf-replay-rate-trace-default --experiment-name=replay_rate_trace --db-path=benchmark_TcpNewReno.db '--parameters={aut:TcpNewReno,trace_file:0.57mbps-poisson.trace}' --aut=TcpNewReno --stop-time=15s --seed=42 --trace-file=0.57mbps-poisson.trace --bw=1Gbps --loss=0.0477 --qlen=14p --qdisc=FifoQueueDisc --rtts=56ms --sources=src_0 --destinations=dst_0 --protocols=TCP --algs=TcpNewReno --recoveries=TcpPrrRecovery --start-times=0s --stop-times=15s '--traffic-models=Greedy(bytes=0)' --trace-dir=/home/zzo/phd/ccperf/ccperf/resources/traces
Flows
| src | dst | transport_protocol | cca | cc_recovery_alg | traffic_model | start_time | stop_time |
|---|---|---|---|---|---|---|---|
| src_0 | dst_0 | TCP | TcpNewReno | TcpPrrRecovery | Greedy(bytes=0) | 0.00 | 15.00 |
Metrics
The following tables list the flow, link, and network metrics of experiment #79. Refer to the the metrics page for definitions of the listed metrics.
Flow Metrics
Flow metrics capture the performance of an individual flow. They are measured at the endpoints of a network path at either the source, the receiver, or both. Bold values indicate which flow achieved the best performance.
| Metric | flow_1 |
|---|---|
| cov_in_flight_l4 | 0.55 |
| cov_throughput_l4 | 0.70 |
| flow_completion_time_l4 | 14.93 |
| mean_cwnd_l4 | 6.46 |
| mean_delivery_rate_l4 | 0.41 |
| mean_est_qdelay_l4 | 87.63 |
| mean_idt_ewma_l4 | 25.81 |
| mean_in_flight_l4 | 6.10 |
| mean_network_power_l4 | 3.12 |
| mean_one_way_delay_l7 | 7346.27 |
| mean_recovery_time_l4 | 360.92 |
| mean_sending_rate_l4 | 0.44 |
| mean_sending_rate_l7 | 2.55 |
| mean_srtt_l4 | 143.63 |
| mean_throughput_l4 | 0.41 |
| mean_throughput_l7 | 0.41 |
| mean_utility_mpdf_l4 | -2.73 |
| mean_utility_pf_l4 | -0.86 |
| mean_utilization_bdp_l4 | inf |
| mean_utilization_bw_l4 | inf |
| total_retransmissions_l4 | 25.00 |
| total_rtos_l4 | 2.00 |
Link Metrics
Link metrics are recorded at the network links of interest, typically at bottlenecks. They include metrics that measure queue states. Bold values indicate which link achieved the best performance.
| Metric | btl_forward |
|---|---|
| mean_qdisc_delay_l2 | 80.54 |
| mean_qdisc_length_l2 | 3.60 |
| mean_sending_rate_l1 | 0.45 |
| total_qdisc_drops_l2 | 1.00 |
Figures
The following figures show the results of the experiment #79.Time Series Plot of the Operating Point
Time series plot of the number of segments in flight, the smoothed round-trip time (sRTT), and the throughput at the transport layer.
Distribution of the Operating Point
The empirical cumulative distribution function (eCDF) of the throughput and smoothed round-trip time (sRTT) at the transport layer of each flow.
Comparison of Congestion Control Algorithms (CCAs)
Figures
