4 - **Frame size**: size of an Ethernet Layer-2 frame on the wire, including
5 any VLAN tags (dot1q, dot1ad) and Ethernet FCS, but excluding Ethernet
6 preamble and inter-frame gap. Measured in Bytes.
7 - **Packet size**: same as frame size, both terms used interchangeably.
8 - **Inner L2 size**: for tunneled L2 frames only, size of an encapsulated
9 Ethernet Layer-2 frame, preceded with tunnel header, and followed by
10 tunnel trailer. Measured in Bytes.
11 - **Inner IP size**: for tunneled IP packets only, size of an encapsulated
12 IPv4 or IPv6 packet, preceded with tunnel header, and followed by
13 tunnel trailer. Measured in Bytes.
14 - **Device Under Test (DUT)**: In software networking, "device" denotes a
15 specific piece of software tasked with packet processing. Such device
16 is surrounded with other software components (such as operating system
17 kernel). It is not possible to run devices without also running the
18 other components, and hardware resources are shared between both. For
19 purposes of testing, the whole set of hardware and software components
20 is called "System Under Test" (SUT). As SUT is the part of the whole
21 test setup performance of which can be measured with :rfc:`2544`, using
22 SUT instead of :rfc:`2544` DUT. Device under test
23 (DUT) can be re-introduced when analyzing test results using whitebox
24 techniques, but this document sticks to blackbox testing.
25 - **System Under Test (SUT)**: System under test (SUT) is a part of the
26 whole test setup whose performance is to be benchmarked. The complete
27 methodology contains other parts, whose performance is either already
28 established, or not affecting the benchmarking result.
29 - **Bi-directional throughput tests**: involve packets/frames flowing in
30 both transmit and receive directions over every tested interface of
31 SUT/DUT. Packet flow metrics are measured per direction, and can be
32 reported as aggregate for both directions (i.e. throughput) and/or
33 separately for each measured direction (i.e. latency). In most cases
34 bi-directional tests use the same (symmetric) load in both directions.
35 - **Uni-directional throughput tests**: involve packets/frames flowing in
36 only one direction, i.e. either transmit or receive direction, over
37 every tested interface of SUT/DUT. Packet flow metrics are measured
38 and are reported for measured direction.
39 - **Packet Loss Ratio (PLR)**: ratio of packets received relative to packets
40 transmitted over the test trial duration, calculated using formula:
41 PLR = ( pkts_transmitted - pkts_received ) / pkts_transmitted.
42 For bi-directional throughput tests aggregate PLR is calculated based
43 on the aggregate number of packets transmitted and received.
44 - **Packet Throughput Rate**: maximum packet offered load DUT/SUT forwards
45 within the specified Packet Loss Ratio (PLR). In many cases the rate
46 depends on the frame size processed by DUT/SUT. Hence packet
47 throughput rate MUST be quoted with specific frame size as received by
48 DUT/SUT during the measurement. For bi-directional tests, packet
49 throughput rate should be reported as aggregate for both directions.
50 Measured in packets-per-second (pps) or frames-per-second (fps),
52 - **Bandwidth Throughput Rate**: a secondary metric calculated from packet
53 throughput rate using formula: bw_rate = pkt_rate - (frame_size +
54 L1_overhead) - 8, where L1_overhead for Ethernet includes preamble (8
55 Bytes) and inter-frame gap (12 Bytes). For bi-directional tests,
56 bandwidth throughput rate should be reported as aggregate for both
57 directions. Expressed in bits-per-second (bps).
58 - **Non Drop Rate (NDR)**: maximum packet/bandwith throughput rate sustained
59 by DUT/SUT at PLR equal zero (zero packet loss) specific to tested
60 frame size(s). MUST be quoted with specific packet size as received by
61 DUT/SUT during the measurement. Packet NDR measured in
62 packets-per-second (or fps), bandwidth NDR expressed in
63 bits-per-second (bps).
64 - **Partial Drop Rate (PDR)**: maximum packet/bandwith throughput rate
65 sustained by DUT/SUT at PLR greater than zero (non-zero packet loss)
66 specific to tested frame size(s). MUST be quoted with specific packet
67 size as received by DUT/SUT during the measurement. Packet PDR
68 measured in packets-per-second (or fps), bandwidth PDR expressed in
69 bits-per-second (bps).
70 - **Maximum Receive Rate (MRR)**: packet/bandwidth rate regardless of PLR
71 sustained by DUT/SUT under specified Maximum Transmit Rate (MTR)
72 packet load offered by traffic generator. MUST be quoted with both
73 specific packet size and MTR as received by DUT/SUT during the
74 measurement. Packet MRR measured in packets-per-second (or fps),
75 bandwidth MRR expressed in bits-per-second (bps).
76 - **Trial**: a single measurement step.
77 - **Trial duration**: amount of time over which packets are transmitted and
78 received in a single throughput measurement step.