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<front>
<title abbrev="Test Scenarios for RMCAT">Test Cases for Evaluating RMCAT
Proposals</title>
<author fullname="Zaheduzzaman Sarker" initials="Z" surname="Sarker">
<organization>Ericsson AB</organization>
<address>
<postal>
<street></street>
<city>Luleå</city>
<region>SE</region>
<code>977 53</code>
<country>Sweden</country>
</postal>
<phone>+46 10 717 37 43</phone>
<email>zaheduzzaman.sarker@ericsson.com</email>
</address>
</author>
<author fullname="Varun Singh" initials="V" surname="Singh">
<organization>Aalto University</organization>
<address>
<postal>
<street>School of Electrical Engineering</street>
<street>Otakaari 5 A</street>
<city>Espoo</city>
<region>FIN</region>
<code>02150</code>
<country>Finland</country>
</postal>
<email>varun@comnet.tkk.fi</email>
<uri>http://www.netlab.tkk.fi/~varun/</uri>
</address>
</author>
<author fullname=" Xiaoqing Zhu" initials="X" surname="Zhu">
<organization>Cisco Systems</organization>
<address>
<postal>
<street>510 McCarthy Blvd</street>
<city>Milpitas</city>
<region>CA</region>
<code>95134</code>
<country>USA</country>
</postal>
<email>xiaoqzhu@cisco.com</email>
</address>
</author>
<author fullname="Michael A. Ramalho" initials="M. A." surname="Ramalho">
<organization abbrev="Cisco Systems">Cisco Systems, Inc.</organization>
<address>
<postal>
<street>6310 Watercrest Way Unit 203</street>
<city>Lakewood Ranch</city>
<region>FL</region>
<code>34202-5211</code>
<country>USA</country>
</postal>
<phone>+1 919 476 2038</phone>
<email>mramalho@cisco.com</email>
</address>
</author>
<date year="2015" />
<area>TSV</area>
<keyword>Multimedia</keyword>
<keyword>Test cases</keyword>
<keyword>Congestion Control</keyword>
<abstract>
<t>The Real-time Transport Protocol (RTP) is used to transmit media in
multimedia telephony applications, these applications are typically
required to implement congestion control. The RMCAT working group is
currently working on candidate algorithms for such interactive real-time
multimedia applications. This document describes the test cases to be
used in the performance evaluation of those candidate algorithms.</t>
<!--The draft defines a structure on how to define test cases and uses
that stracture to define test case those are essensial to RMCAT to evaluate
the candidate algorithms. also the intention here is define the test cases
in such a way that people can customize by tunning the same test case to fit
their to be tested network characteristics. this is the theme and we need
more text here.-->
</abstract>
</front>
<middle>
<section title="Introduction">
<t>This memo describes a set of test cases for evaluating candidate
RMCAT congestion control algorithm proposals, it is based on the
guidelines enumerated in <xref
target="I-D.ietf-rmcat-eval-criteria"></xref> and the requirements
discussed in <xref target="I-D.ietf-rmcat-cc-requirements"></xref>. The
test cases cover basic usage scenarios and are described using a common
structure, which allows for additional test cases to be added to those
described herein to accommodate other topologies and/or the modeling of
different path characteristics. It is the intention of this work to
capture the consensus of the RMCAT working group participants regarding
the test cases upon which the performance of the candidate RMCAT
proposals should be evaluated.</t>
</section>
<section anchor="sec-terminology" title="Terminology">
<!--<t> The key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
"SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described
in BCP 14, <xref target="RFC2119" /> and indicate requirement
levels for compliant implementations. </t> -->
<t>The terminology defined in <xref target="RFC3550">RTP</xref>, <xref
target="RFC3551">RTP Profile for Audio and Video Conferences with
Minimal Control</xref>, <xref target="RFC3611">RTCP Extended Report
(XR)</xref>, <xref target="RFC4585">Extended RTP Profile for RTCP-based
Feedback (RTP/AVPF)</xref>, <xref target="RFC5506">Support for
Reduced-Size RTCP</xref>, and <xref
target="I-D.ietf-avtcore-rtp-circuit-breakers">RTP Circuit Breaker
algorithm</xref> apply.</t>
</section>
<section anchor="TS" title="Structure of Test cases">
<t>All test cases in this document follow a basic structure allowing
implementers to describe a new test scenario without repeatedly
explaining common attributes. The structure includes a general
description section that describes the test case and its motivation.
Additionally the test case defines a set of attributes that characterize
the testbed, i.e., the network path between communicating peers and the
diverse traffic sources.</t>
<t><list style="symbols">
<t>Define the test case: <list style="symbols">
<t>General description: describes the motivation and the goals
of the test case.</t>
<t>Expected behavior: describe the desired rate adaptation
behaviour.</t>
<t>Define a check-list to evaluate the desired behaviour: this
indicates the minimum set of metrics (e.g., link utilization,
media sending rate) that a proposed algorithm needs to measure
to validate the expected rate adaptation behaviour. It should
also indicate the time granularity (e.g., averaged over 10ms,
100ms, or 1s) for measuring certain metrics. Typical measurement
interval is 200ms.</t>
<!-- we agreed this should be 200ms or was it based on some IPPM doc? -->
</list></t>
<t>Define testbed topology: every test case needs to define an
evaluation testbed topology. <xref target="fig-eval-topo"></xref>
shows such an evaluation topology. In this evaluation topology,
S1..Sn are traffic sources. These sources generate media traffic and
use either an RMCAT candidate congestion control algorithm or other
congestion control algorithm designed for media, such as TFRC.
R1..Rn are the corresponding receivers. A test case can have one or
more such traffic sources (S) and corresponding receivers (R). The
path from the source to destination is denoted as forward and the
path from a destination to a source is denoted as backward. The
following basic structure of test case has been described from the
perspective of media generating endpoints attached on the left-hand
side of <xref target="fig-eval-topo"></xref>. In this setup, media
flows in forward direction and corresponding feedback/control
messages flow in the backward direction. However, it is also
possible to set up the test with media flowing in both forward and
backward directions. In that case, unless otherwise specified by the
test case, it is expected that the backward path does not introduce
any congestion related impairments and has enough capacity to
accommodate both media and feedback/control messages. It should be
noted that depending on the test cases it is possible to have
different path characteristics in of the either directions.</t>
<t><figure anchor="fig-eval-topo"
title="Example of A Testbed Topology">
<artwork><![CDATA[
+---+ +---+
|S1 |====== \ Forward --> / =======|R1 |
+---+ \\ // +---+
\\ //
+---+ +-----+ +-----+ +---+
|S2 |=======| A |------------------------------>| B |=======|R2 |
+---+ | |<------------------------------| | +---+
+-----+ +-----+
(...) // \\ (...)
// <-- Backward \\
+---+ // \\ +---+
|Sn |====== / \ ======|Rn |
+---+ +---+
]]></artwork>
</figure>In a laboratory testbed environment there may exist a
significant amount of traffic on portions of the network path
between the endpoints that is not desired for the purposes of these
RMCAT tests. Some of this traffic may be generated by other
processes on the endpoints themselves (e.g., discovery protocols) or
by other endpoints not presently under test. It is recommended not
to route traffic generated by endpoints that are not under test
through the test bed. Additionally, it is recommended to route
non-RMCAT traffic generated by the endpoints under test around the
bottleneck links specified herein.</t>
<t>Define testbed attributes: <list style="symbols">
<t>Duration: defines the duration of the test.</t>
<t>Path characteristics: defines the end-to-end transport level
path characteristics of the testbed in a particular test case.
Two sets of attributes describe the path characteristics, one
for the forward path and the other for the backward path. The
path characteristics for a particular path direction is
applicable to all the Sources "S" sending traffic on that path.
If only one attribute is specified, it is used for both path
directions, however, unless specified the reverse path has no
capacity restrictions and no path loss.
<list style="symbols">
<t>Path direction: forward or backward.</t>
<t>Bottleneck-link capacity: defines minimum capacity of the
end-to-end path</t>
<t>One-way propagation delay: describes the end-to-end
latency along the path when network queues are empty, i.e.,
the time it takes for a packet to go from the sender to the
receiver without encountering any queuing delay.</t>
<t>Maximum end-to-end jitter: defines the maximum jitter
that can be observed along the path.</t>
<t>Bottleneck queue type: for example, Droptail, FQ-CoDel,
or PIE.</t>
<t>Bottleneck queue size: defines size of queue in terms of
queuing time when the queue is full (in milliseconds).</t>
<t>Path loss ratio: characterizes the non-congested,
additive, losses to be generated on the end-to-end path.
MUST describe the loss pattern or loss model used to
generate the losses.</t>
<t>Values for some characteristics are described in
<xref target="I-D.ietf-rmcat-eval-criteria"></xref>.</t>
</list></t>
<t>Application-related: defines the traffic source behaviour for
implementing the test case <list style="symbols">
<t>Media traffic Source: defines the characteristics of the
media sources. When using more than one media source, the
different attributes are enumerated separately for each
different media source. <list style="symbols">
<t>Media type: Video/Voice/Application/Text</t>
<!-- VS: we should remove Application/text because, we
currently have no media source behaviour for them. -->
<t>Media flow direction: forward, backward or both.</t>
<t>Number of media sources: defines the total number of
media sources</t>
<t>Media codec: Constant Bit Rate (CBR) or Variable Bit
Rate (VBR)</t>
<t>Media source behaviour: describes the media encoder
behavior. It defines the main parameters that affect the
adaptation behaviour. This may include but not limited
to: <list style="symbols">
<t>Adaptability: describes the adaptation options.
For example, in the case of video it defines the
following ranges of adaptation: bit rate, frame
rate, video resolution. Similarly, in the case of
voice, it defines the range of bit rate adaptation,
the sampling rate variation, and the variation in
packetization interval.</t>
<t>Output variation : for a VBR encoder it defines
the encoder output variation from the average target
rate over a particular measurement interval. For
example, on average the encoder output may vary
between 5% to 15% above or below the average target
bit rate when measured over a 100 ms time window.
The time interval over which the variation is
specified must be provided.</t>
<!-- VS: I suppose this applies to traffic models
and not to real codecs. Zahed, perhaps just adding
media source model instead of source behavior? -->
<t>Responsiveness to a new bit rate request: the lag
in time between a new bit rate request and actual
rate changes in encoder output. Depending on the
encoder, this value may be specified in absolute
time (e.g. 10ms to 1000ms) or other appropriate
metric (next frame interval time).</t>
</list></t>
<t>Media content: describes the chosen media sequences;
For example, test sequences are available at: <xref
target="xiph-seq"></xref> and <xref
target="HEVC-seq"></xref>.</t>
<t>Media timeline: describes the point when the media
source is introduced and removed from the testbed. For
example, the media source may start transmitting
immediately when the test case begins, or after a few
seconds.</t>
<t>Startup behaviour: the media starts at a defined bit
rate, which may be the minimum, maximum bit rate, or a
value in between (in Kbps).</t>
</list></t>
<t>Competing traffic source: describes the characteristics
of the competing traffic source, the different types of
competing flows are enumerated in <xref
target="I-D.ietf-rmcat-eval-criteria"></xref>. <list
style="symbols">
<t>Traffic direction: forward, backward or both.</t>
<t>Type of sources: defines the types of competing
traffic sources. Types of competing traffic flows are
listed in <xref
target="I-D.ietf-rmcat-eval-criteria"></xref>. For
example, the number of TCP flows connected to a web
browser, the mean size and distribution of the content
downloaded.</t>
<t>Number of sources: defines the total number of
competing sources of each media type.</t>
<t>Congestion control: enumerates the congestion control
used by each type of competing traffic.</t>
<t>Traffic timeline: describes when the competing
traffic starts and ends in the test case.</t>
</list></t>
</list></t>
<t>Additional attributes: describes attributes essential for
implementing a test case which are not included in the above
structure. These attributes MUST be well defined, so that other
implementers are able to implement it.</t>
</list></t>
</list></t>
<t>Any attribute can have a set of values (enclosed within "[]"). Each
member value of such a set MUST be treated as different value for the
same attribute. It is desired to run separate tests for each such
attribute value.</t>
<t>The test cases described in this document follow the above
structure.</t>
</section>
<section anchor="sec-rec-eval" title="Recommended Evaluation Settings">
<t>This section describes recommended test case settings and could be
overwritten by the respective test cases.</t>
<section anchor="EM" title="Evaluation metircs">
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the following metrics
at a fine enough time granularity: <list style="numbers">
<t>Flow level: <list style="letters">
<t>End-to-end delay for the RMCAT flow.</t>
<t>Variation in sending bit rate and goodput. Mainly observing
the frequency and magnitude of oscillations.</t>
<t>Packet losses observed at the receiving endpoint</t>
<t>Feedback message overhead</t>
<t>Convergence time.</t>
</list></t>
<t>Transport level: <list style="letters">
<t>Bandwidth utilization</t>
<t>Queue length (milliseconds at specified path capacity):
<list style="symbols">
<t>average over the length of the session</t>
<t>5 and 95 percentile</t>
<t>median, maximum, minimum</t>
</list></t>
</list></t>
</list></t>
</section>
<section anchor="PC" title="Path characteristics">
<t>Each path between a sender and receiver as described in <xref
target="fig-eval-topo"></xref> have the following characteristics
unless otherwise specified in the test case.
<list style="symbols">
<t>Path direction: forward and backward.</t>
<t>Bottleneck-link capacity: 4Mbps.</t>
<t>One-Way propagation delay: 50ms. It is encouraged to test with
additional propagation delays mentioned in
<xref target="I-D.ietf-rmcat-eval-criteria" /></t>
<t>Maximum end-to-end jitter: 30ms. Jitter models are described in
<xref target="I-D.ietf-rmcat-eval-criteria" /></t>
<t>Bottleneck queue type: Drop tail. It is encouraged to test with
other AQM schemes, such as FQ-CoDel and PIE.</t>
<t>Bottleneck queue size: 300ms.</t>
<t>Path loss ratio: 0%.</t>
</list></t>
<t>Examples of additional network parameters are discussed in
<xref target="I-D.ietf-rmcat-eval-criteria" />.</t>
</section>
<section anchor="MS" title="Media source">
<t>Unless otherwise specified, each test case will include one or more
media sources as described below. <list style="symbols">
<t>Media type: Video <list style="symbols">
<t>Media codec: VBR</t>
<t>Media source behaviour: <list style="symbols">
<t>Adaptability: <list style="symbols">
<t>Bit rate range: 150 Kbps - 1.5 Mbps. In real-life
applications the bitrate range can vary a lot
depending on the provided service, for example, the
maximum bitrate can be up to 4Mbps. However, for
running tests to evaluate the congestion control
algorithms it is more important to have a look at how
they are reacting to certain amount of bandwidth
change. Also it is possible that the media traffic
generator used in a particular simulator or testbed if
not capable of generating higher bitrate. Hence we
have selected a suitable bitrate range typical of
consumer-grade video conferencing applications in
designing the test case. If a different bitrate range
is used in the test cases, the end-to-end path
capacity values will also need to be scaled
accordingly.</t>
<t>Frame resolution: 144p - 720p (or 1080p)</t>
<t>Frame rate: 10fps - 30fps</t>
</list></t>
<t>Variation from target bitrate: +/-5%. Unless otherwise
specified in the test case, bitrate variation SHOULD be
calculated over one (1) second period of time.</t>
<t>Responsiveness to new bit rate request: 100ms</t>
</list></t>
<t>Media content: The media content should represent a typical
video conversational scenario with head and shoulder movement.
We recommend to use Foreman video sequence.</t>
<t>Media startup behaviour: 150Kbps. It should be noted that
applications can use smart ways to select an optimal startup
bitrate values for a certain network condition. In such cases
the candidate proposals MAY show the effectiveness of such
smart approach as an additional information for the evaluation
process.</t>
</list></t>
</list><list style="symbols">
<t>Media type: Audio<list style="symbols">
<t>Media codec: CBR</t>
<t>Media bitrate: 20Kbps</t>
</list></t>
</list></t>
</section>
</section>
<section anchor="TC" title="Basic Test Cases">
<section anchor="VACS"
title="Variable Available Capacity with Single RMCAT flow">
<t>In this test case the bottleneck-link capacity between the two
endpoints varies over time. This test is designed to measure the
responsiveness of the candidate algorithm. This test tries to address
the requirements in <xref
target="I-D.ietf-rmcat-cc-requirements"></xref>, which requires the
algorithm to adapt the flow(s) and provide lower end-to-end latency
when there exists: <list style="symbols">
<t>an intermediate bottleneck</t>
<t>change in available capacity (e.g., due to interface change,
routing change).</t>
<t>maximum Media Bit Rate is Greater than Link Capacity. In this
case, the application will attempt to ramp up to its maximum bit
rate, since the link capacity is limited to a value lower, the
congestion control scheme is expected to stabilize the sending bit
rate close to the available bottleneck capacity. This situation
can occur when the endpoints are connected via thin long networks
even though the advertised capacity of the access network may be
higher.</t>
<!-- XZ: the above text may need to be removed? -->
</list>It should be noted that the exact variation in available
capacity due to any of the above depends on the under-lying
technologies. Hence, we describe a set of known factors, which may be
extended to devise a more specific test case targeting certain
behaviour in a certain network environment.</t>
<t>Expected behavior: the candidate algorithm is expected to detect
the path capacity constraint, converges to bottleneck link's capacity
and adapt the flow to avoid unwanted oscillation when the sending bit
rate is approaching the bottleneck link's capacity. The oscillations
occur when the media flow(s) attempts to reach its maximum bit rate,
overshoots the usage of the available bottleneck capacity, to rectify
it reduces the bit rate and starts to ramp up again.</t>
<t>Testbed topology: One media source S1 is connected to corresponding
R1. The media traffic is transported over the forward path and
corresponding feedback/control traffic is transported over the
backward path. <figure anchor="fig-eval-topo-4-2"
title="Testbed Topology for Limited Link Capacity">
<artwork><![CDATA[
Forward -->
+---+ +-----+ +-----+ +---+
|S1 |=======| A |------------------------------>| B |=======|R1 |
+---+ | |<------------------------------| | +---+
+-----+ +-----+
<-- Backward
]]></artwork>
</figure></t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the metrics described
in <xref target="EM"></xref> at a fine enough time granularity.</t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 100s</t>
<t>Path characteristics: as described in <xref
target="PC"></xref></t>
<t>Application-related: <list style="symbols">
<t>Media Traffic:<list style="symbols">
<t>Media type: Video<list style="symbols">
<t>Media direction: forward.</t>
<t>Number of media sources: One (1)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 0s.</t>
<t>End time: 99s.</t>
</list></t>
</list></t>
<t>Media type: Audio<list style="symbols">
<t>Media direction: forward.</t>
<t>Number of media sources: One (1)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 0s.</t>
<t>End time: 99s.</t>
</list></t>
</list></t>
</list></t>
<t>Competing traffic: <list style="symbols">
<t>Number of sources : Zero (0)</t>
</list></t>
</list></t>
<t>Test Specific Information: <list style="symbols">
<t>This test uses the following one way propagation delays of
50 ms and 100 ms.</t>
<t>This test uses bottleneck path capacity variation as listed
in <xref target="VACS_US"></xref></t>
</list></t>
</list></t>
<texttable anchor="VACS_US"
title="Path capacity variation pattern for forward direction">
<ttcol>Variation pattern index</ttcol>
<ttcol>Path direction</ttcol>
<ttcol>Start time</ttcol>
<ttcol>Path capacity</ttcol>
<c>One</c>
<c>Forward</c>
<c>0s</c>
<c>1Mbps</c>
<c>Two</c>
<c>Forward</c>
<c>40s</c>
<c>2.5Mbps</c>
<c>Three</c>
<c>Forward</c>
<c>60s</c>
<c>600Kbps</c>
<c>Four</c>
<c>Forward</c>
<c>80s</c>
<c>1Mbps</c>
<!-- <postamble>Table 1: Path capacity variation pattern for
forward direction</postamble> -->
</texttable>
<t></t>
</section>
<section anchor="VACM"
title="Variable Available Capacity with Multiple RMCAT flows">
<t>This test case is similar to <xref target="VACS"></xref>. However
in addition this test will also consider persistent network load due
to competing traffic.</t>
<t>Expected behavior: the candidate algorithms is expected to detect
the variation in available capacity and adapt the media stream(s)
accordingly. The flows stabilize around their maximum bitrate as the
as the maximum link capacity is large enough to accommodate the flows.
When the available capacity drops, the flow(s) adapts by decreasing
its sending bit rate, and when congestion disappears, the flow(s) are
again expected to ramp up.</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the metrics described
in <xref target="EM"></xref> at a fine enough time granularity:</t>
<t>Testbed Topology: Two (2) media sources S1 and S2 are connected to
their corresponding destinations R1 and R2. The media traffic is
transported over the forward path and corresponding feedback/control
traffic is transported over the backward path. <figure
anchor="fig-eval-topo-4-1"
title="Testbed Topology for Variable Available Capacity">
<artwork><![CDATA[
+---+ +---+
|S1 |===== \ / =======|R1 |
+---+ \\ Forward --> // +---+
\\ //
+-----+ +-----+
| A |------------------------------>| B |
| |<------------------------------| |
+-----+ +-----+
// \\
// <-- Backward \\
+---+ // \\ +---+
|S2 |====== / \ ======|R2 |
+---+ +---+
]]></artwork>
</figure></t>
<t>Testbed attributes:</t>
<t>Testbed attributes are similar as described in <xref
target="VACS"></xref> except the test specific capacity variation
setup.</t>
<t>Test Specific Information: This test uses path capacity variation
as listed in <xref target="VACM_US"></xref> with a corresponding end
time of 125 seconds.</t>
<texttable anchor="VACM_US"
title="Path capacity variation pattern for forward direction">
<ttcol>Variation pattern index</ttcol>
<ttcol>Path direction</ttcol>
<ttcol>Start time</ttcol>
<ttcol>Path capacity</ttcol>
<c>One</c>
<c>Forward</c>
<c>0s</c>
<c>4Mbps</c>
<c>Two</c>
<c>Forward</c>
<c>25s</c>
<c>2Mbps</c>
<c>Three</c>
<c>Forward</c>
<c>50s</c>
<c>3.5Mbps</c>
<c>Four</c>
<c>Forward</c>
<c>75s</c>
<c>1Mbps</c>
<c>Five</c>
<c>Forward</c>
<c>100s</c>
<c>2Mbps</c>
<!-- <postamble>Table 2: Path capacity variation pattern for
forward direction</postamble> -->
</texttable>
</section>
<section anchor="CFL"
title="Congested Feedback Link with Bi-directional RMCAT flows">
<t>RMCAT WG has been chartered to define algorithms for RTP hence it
is assumed that RTCP, RTP header extension or such would be used by
the congestion control algorithm in the backchannel. Due to asymmetric
nature of the link between communicating peers it is possible for a
participating peer to not receive such feedback information due to an
impaired or congested backchannel (even when the forward channel might
not be impaired). This test case is designed to observe the candidate
congestion control behaviour in such an event.</t>
<t>It is expected that the candidate algorithms is able to cope with
the lack of feedback information and adapt to minimize the performance
degradation of media flows in the forward channel.</t>
<t>It should be noted that for this test case: logs are compared with
the reference case, i.e, when the backward channel has no
impairments</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the metrics described
in <xref target="EM"></xref> at a fine-grained time intervals:</t>
<t>Testbed topology: One (1) media source S1 is connected to
corresponding R1, but both endpoints are additionally receiving and
sending data, respectively. The media traffic (S1->R1) is
transported over the forward path and corresponding feedback/control
traffic is transported over the backward path. Likewise media traffic
(S2->R2) is transported over the backward path and corresponding
feedback/control traffic is transported over the forward path.</t>
<t><figure anchor="fig-eval-topo-4-6"
title="Testbed Topology for Congested Feedback Link">
<artwork><![CDATA[
+---+ +---+
|S1 |===== \ Forward --> / =======|R1 |
+---+ \\ // +---+
\\ //
+-----+ +-----+
| A |------------------------------>| B |
| |<------------------------------| |
+-----+ +-----+
// \\
// <-- Backward \\
+---+ // \\ +---+
|R2 |===== / \ ======|S2 |
+---+ +---+
]]></artwork>
</figure></t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 100s</t>
<t>Path characteristics: <list style="symbols">
<t>Bottleneck-link capacity: 2Mbps.</t>
</list></t>
<t>Application-related: <list style="symbols">
<t>Media Source: <list style="symbols">
<t>Media type: Video<list style="symbols">
<t>Media direction: forward and backward</t>
<t>Number of media sources: Two (2)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 0s.</t>
<t>End time: 99s.</t>
</list></t>
</list></t>
<t>Media type: Audio<list style="symbols">
<t>Media direction: forward and backward</t>
<t>Number of media sources: Two (2)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 0s.</t>
<t>End time: 99s.</t>
</list></t>
</list></t>
</list></t>
<t>Competing traffic: <list style="symbols">
<t>Number of sources : Zero (0)</t>
</list></t>
</list></t>
<t>Test Specific Information: This test uses path capacity
variations to create congested feedback link. <xref
target="CFL_US"> </xref> lists the variation patterns applied to
the forward path and <xref target="CFL_DS"></xref> lists the
variation patterns applied to the backward path.</t>
</list></t>
<texttable anchor="CFL_US"
title="Path capacity variation pattern for forward direction">
<ttcol>Variation pattern index</ttcol>
<ttcol>Path direction</ttcol>
<ttcol>Start time</ttcol>
<ttcol>Path capacity</ttcol>
<c>One</c>
<c>Forward</c>
<c>0s</c>
<c>2Mbps</c>
<c>Two</c>
<c>Forward</c>
<c>20s</c>
<c>1Mbps</c>
<c>Three</c>
<c>Forward</c>
<c>40s</c>
<c>500Kbps</c>
<c>Four</c>
<c>Forward</c>
<c>60s</c>
<c>2Mbps</c>
<!-- <postamble>Table 3: Path capacity variation pattern for
forward direction</postamble> -->
</texttable>
<t></t>
<texttable anchor="CFL_DS"
title="Path capacity variation pattern for backward direction">
<ttcol>Variation pattern index</ttcol>
<ttcol>Path direction</ttcol>
<ttcol>Start time</ttcol>
<ttcol>Path capacity</ttcol>
<c>One</c>
<c>Backward</c>
<c>0s</c>
<c>2Mbps</c>
<c>Two</c>
<c>Backward</c>
<c>35s</c>
<c>800Kbps</c>
<c>Three</c>
<c>Backward</c>
<c>70s</c>
<c>2Mbps</c>
<!-- <postamble>Table 4: Path capacity variation pattern for
backward direction</postamble> -->
</texttable>
</section>
<section anchor="competing-rmcat-flow"
title="Competing Flows with Same RMCAT Algorithm">
<t>In this test case, more than one RMCAT media flow shares the
bottleneck link and each of them uses the same congestion control
algorithm. This is a typical scenario where a real-time interactive
application sends more than one media flows to the same destination
and these flows are multiplexed over the same port. In such a scenario
it is likely that the flows will be routed via the same path and need
to share the available bandwidth amongst themselves. For the sake of
simplicity it is assumed that there are no other non-RMCAT competing
traffic sources in the bottleneck link and that there is sufficient
capacity to accommodate all the flows individually. While this appears
to be a variant of the test case defined in <xref
target="VACM"></xref>, it focuses on the capacity sharing aspect of
the candidate algorithm. The previous test case, on the other hand,
measures adaptability, stability, and responsiveness of the candidate
algorithm.</t>
<t>Expected behavior: It is expected that the competing flows will
converge to an optimum bit rate to accommodate all the flows with
minimum possible latency and loss. Specifically, the test introduces
three media flows at different time instances, when the second flow
appears there should still be room to accommodate another flow on the
bottleneck link. Lastly, when the third flow appears the bottleneck
link should be saturated.</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the metrics described
in <xref target="EM"></xref> at a fine enough time granularity:</t>
<t>Testbed topology: Three media sources S1, S2, S3 are connected to
respective R1, R2, R3. The media traffic is transported over the
forward path and corresponding feedback/control traffic is transported
over the backward path. <figure anchor="fig-eval-topo-4-3"
title="Testbed Topology for Multiple RMCAT Flows">
<artwork><![CDATA[
+---+ +---+
|S1 |===== \ Forward --> / =======|R1 |
+---+ \\ // +---+
\\ //
+---+ +-----+ +-----+ +---+
|S2 |=======| A |------------------------------>| B |=======|R2 |
+---+ | |<------------------------------| | +---+
+-----+ +-----+
// \\
// <-- Backward \\
+---+ // \\ +---+
|S3 |====== / \ ======|R3 |
+---+ +---+
]]></artwork>
</figure></t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 120s</t>
<t>Path characteristics: <list style="symbols">
<t>Bottleneck-link capacity: 3.5Mbps</t>
<!-- <t>One-Way propagation delay: [10ms, 50ms]</t> -->
</list></t>
<t>Application-related: <list style="symbols">
<t>Media Source: <list style="symbols">
<t>Media type: Video<list style="symbols">
<t>Media direction: forward.</t>
<t>Number of media sources: Three (3)</t>
<t>Media timeline: New media flows are added
sequentially, at short time intervals. See test
specific setup below.</t>
</list></t>
<t>Media type: Audio<list style="symbols">
<t>Media direction: forward.</t>
<t>Number of media sources: Three (3)</t>
<t>Media timeline: New media flows are added
sequentially, at short time intervals. See test
specific setup below.</t>
</list></t>
</list></t>
<t>Competing traffic: <list style="symbols">
<t>Number of sources : Zero (0)</t>
</list></t>
</list></t>
<t>Test Specific Information: <xref target="MTL_CF"></xref>
defines the media timeline for both media type.</t>
</list></t>
<texttable anchor="MTL_CF"
title="Media Timeline for Video and Audio media sources">
<ttcol>Flow IF</ttcol>
<ttcol>Media type</ttcol>
<ttcol>Start time</ttcol>
<ttcol>End time</ttcol>
<c>1</c>
<c>Video</c>
<c>0s</c>
<c>119s</c>
<c>2</c>
<c>Video</c>
<c>20s</c>
<c>119s</c>
<c>3</c>
<c>Video</c>
<c>40s</c>
<c>119s</c>
<c>4</c>
<c>Audio</c>
<c>0s</c>
<c>119s</c>
<c>5</c>
<c>Audio</c>
<c>20s</c>
<c>119s</c>
<c>6</c>
<c>Audio</c>
<c>40s</c>
<c>119s</c>
</texttable>
</section>
<section title="Round Trip Time Fairness">
<t>In this test case, multiple RMCAT media flows share the bottleneck
link, but the end-to-end path latency for each RMCAT flow is
different. For the sake of simplicity it is assumed that there are no
other non-RMCAT competing traffic sources in the bottleneck link and
that there is sufficient capacity to accommodate all the flows. While
this appears to be a variant of test case 5.2, it focuses on the
capacity sharing aspect of the candidate algorithm under different
RTTs.</t>
<t>It is expected that the competing flows will converge to bit rates
to accommodate all the flows with minimum possible latency and loss.
Specifically, the test introduces five media flows at the same time
instance.</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the metrics described
in <xref target="EM"></xref> at a fine enough time granularity:</t>
<t>Testbed Topology: Five (5) media sources S1,S2,..,S5 are connected
to their corresponding media sinks R1,R2,..,R5. The media traffic is
transported over the forward path and corresponding feedback/control
traffic is transported over the backward path. The topology is the
same as in <xref target="competing-rmcat-flow"></xref>. The end-to-end
path delays are: 10ms for S1-R1, 25ms for S2-R2, 50ms for S3-R3, 100ms
for S4-R4, and 150ms S5-R5, respectively.</t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 300s</t>
<t>Path characteristics: <list style="symbols">
<t>One-Way propagation delay for each flow: 10ms, 25ms, 50ms,
100ms, 150ms.</t>
</list></t>
<t>Application-related: <list style="symbols">
<t>Media Source: <list style="symbols">
<t>Media type: Video<list style="symbols">
<t>Media direction: forward</t>
<t>Number of media sources: Five (5)</t>
<t>Media timeline: New media flows are added
sequentially, at short time intervals. See test
specific setup below.</t>
</list></t>
<t>Media type: Audio<list style="symbols">
<t>Media direction: forward.</t>
<t>Number of media sources: Five (5)</t>
<t>Media timeline: New media flows are added
sequentially, at short time intervals. See test
specific setup below.</t>
</list></t>
</list></t>
<t>Competing traffic: <list style="symbols">
<t>Number of sources : Zero (0)</t>
</list></t>
</list></t>
<t>Test Specific Information: <xref target="MTL_RTT"></xref>
defines the media timeline for both media type. </t>
</list></t>
<texttable anchor="MTL_RTT"
title="Media Timeline for Video and Audio media sources">
<ttcol>Flow IF</ttcol>
<ttcol>Media type</ttcol>
<ttcol>Start time</ttcol>
<ttcol>End time</ttcol>
<c>1</c>
<c>Video</c>
<c>0s</c>
<c>299s</c>
<c>2</c>
<c>Video</c>
<c>10s</c>
<c>299s</c>
<c>3</c>
<c>Video</c>
<c>20s</c>
<c>299s</c>
<c>4</c>
<c>Video</c>
<c>30s</c>
<c>299s</c>
<c>5</c>
<c>Video</c>
<c>40s</c>
<c>299s</c>
<c>6</c>
<c>Audio</c>
<c>0</c>
<c>299s</c>
<c>7</c>
<c>Audio</c>
<c>10s</c>
<c>299s</c>
<c>8</c>
<c>Audio</c>
<c>20s</c>
<c>299s</c>
<c>9</c>
<c>Audio</c>
<c>30s</c>
<c>299s</c>
<c>10</c>
<c>Audio</c>
<c>40s</c>
<c>299s</c>
</texttable>
</section>
<section title="RMCAT Flow competing with a long TCP Flow">
<t>In this test case, one or more RMCAT media flows share the
bottleneck link with at least one long lived TCP flows. Long lived TCP
flows download data throughout the session and are expected to have
infinite amount of data to send and receive. This is a scenario where
a multimedia application co-exists with a large file download. The
test case measures the adaptivity of the candidate algorithm to
competing traffic. It addresses the requirement 3 in <xref
target="I-D.ietf-rmcat-cc-requirements"></xref>.</t>
<t>Expected behavior: depending on the convergence observed in test
case 5.1 and 5.2, the candidate algorithm may be able to avoid
congestion collapse. In the worst case, the media stream will fall to
the minimum media bit rate.</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the following metrics
in addition to the metrics described in <xref target="EM"></xref> at a
fine enough time granularity: <list style="numbers">
<t>Flow level: <list style="letters">
<t>TCP throughput.</t>
</list></t>
</list></t>
<t>Testbed topology: One (1) media source S1 is connected to
corresponding media sink, R1. In addition, there is a long-live TCP
flow sharing the same bottleneck link. The media traffic is
transported over the forward path and corresponding feedback/control
traffic is transported over the backward path. The TCP traffic goes
over the forward path from, S_tcp with acknowledgement packets flowing
along the backward path from, R_tcp.</t>
<t><figure anchor="fig-eval-topo-4-4"
title="Testbed Topology for TCP vs RMCAT Flows">
<artwork><![CDATA[
+--+ +--+
|S1|===== \ Forward --> / =======|R1|
+--+ \\ // +--+
\\ //
+-----+ +-----+
| A |---------------------------->| B |
| |<----------------------------| |
+-----+ +-----+
// \\
// <-- Backward \\
+-----+ // \\ +-----+
|S_tcp|=== / \ ===|R_tcp|
+-----+ +-----+
]]></artwork>
</figure></t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 120s</t>
<t>Path characteristics: <list style="symbols">
<t>Bottleneck-link capacity: 2Mbps</t>
<!-- <t>One-Way propagation delay: [10ms, 150ms]</t> -->
<t>Bottleneck queue size: [20ms, 300ms, 1000ms]</t>
</list></t>
<t>Application-related: <list style="symbols">
<t>Media Source: <list style="symbols">
<t>Media type: Video<list style="symbols">
<t>Media direction: forward</t>
<t>Number of media sources: One (1)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 5s.</t>
<t>End time: 119s.</t>
</list></t>
</list></t>
<t>Media type: Audio<list style="symbols">
<t>Media direction: forward</t>
<t>Number of media sources: One (1)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 5s.</t>
<t>End time: 119s.</t>
</list></t>
</list></t>
</list></t>
<t>Additionally, implementers are encouraged to run the
experiment with multiple media sources.</t>
<t>Competing traffic: <list style="symbols">
<t>Number and Types of sources : one (1), long-lived
TCP</t>
<t>Traffic direction : forward</t>
<t>Congestion control: Default TCP congestion control.</t>
<t>Traffic timeline: <list style="symbols">
<t>Start time: 0s.</t>
<!--ZS: now a days TCP implementation uses
different techniques like auto tuning, hence if media and data traffic
start at the same the receiver window may be tuned in a way that it does
not grow more than a certain value. Hence this test case will require a
wamp-up time where TCP settings are settled down. However, this also
means we need to make sure the warm-up session does not sature the link
capacity when the media flows are inserted.-->
<!-- VS: I think we can split into 3 cases, TCP starts before, TCP starts
together with media, TCP starts after media. How does that sound? -->
<t>End time: 119s.</t>
</list></t>
</list></t>
<!--Zs: should we not indicate the amount of data download TCP should do?-->
</list></t>
<t>Test Specific Information: None</t>
</list></t>
</section>
<section title="RMCAT Flow competing with short TCP Flows">
<t>In this test case, one or more RMCAT media flow shares the
bottleneck link with multiple short-lived TCP flows. Short-lived TCP
flows resemble the on/off pattern observed in the web traffic, wherein
clients (browsers) connect to a server and download a resource
(typically a web page, few images, text files, etc.) using several TCP
connections (up to 4). This scenario shows the performance of the
multimedia application when several browser windows are active. The
test case measures the adaptivity of the candidate algorithm to
competing web traffic, it addresses the requirements 1.E in <xref
target="I-D.ietf-rmcat-cc-requirements"></xref>.</t>
<t>Depending on the number of short TCP flows, the cross-traffic
either appears as a short burst flow or resembles a long TCP flow. The
intention of this test is to observe the impact of short-term burst on
the behaviour of the candidate algorithm.</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the following metrics
in addition to the metrics described in <xref target="EM"></xref> at a
fine enough time granularity: <list style="numbers">
<t>Flow level: <list style="letters">
<t>Variation in the sending rate of the TCP flow.</t>
<t>TCP throughput.</t>
</list></t>
</list></t>
<t>Testbed topology: The topology described here is same as the one
described in <xref target="fig-eval-topo-4-4"></xref>.</t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 300s</t>
<t>Path characteristics: <list style="symbols">
<t>Bottleneck-link capacity: 2.0Mbps</t>
<!-- <t>One-Way propagation delay: [10ms, 150ms]</t> -->
</list></t>
<t>Application-related: <list style="symbols">
<t>Media Source: <list style="symbols">
<t>Media type: Video<list style="symbols">
<t>Media direction: forward</t>
<t>Number of media sources: two (2)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 5s.</t>
<t>End time: 299s.</t>
</list></t>
</list></t>
<t>Media type: Audio<list style="symbols">
<t>Media direction: forward</t>
<t>Number of media sources: two (2)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 5s.</t>
<t>End time: 299s.</t>
</list></t>
</list></t>
</list></t>
<t>Competing traffic: <list style="symbols">
<t>Number and Types of sources : Ten (10), short-lived TCP
flows.</t>
<t>Traffic direction : forward</t>
<t>Congestion algorithm: Default TCP Congestion
control.</t>
<t>Traffic timeline: Each short TCP flow is modeled as a
sequence of file downloads interleaved with idle periods.
See test specific setup. Not all short TCPs start at the
same time, 2 start in the ON state while 8 start in an OFF
stats. The model for the idle times for the OFF state is
discussed in the Short-TCP model.</t>
</list></t>
</list></t>
<t>Test Specific Information: <list style="symbols">
<t>Short-TCP traffic model: <list style="symbols">
<t>File sizes: uniform distribution between 100KB to
1MB</t>
<t>Idle period: the duration of the OFF state is derived
from an exponential distribution with the mean value of 10
seconds.</t>
</list></t>
</list></t>
</list></t>
</section>
<section title="Media Pause and Resume">
<t>In this test case, more than one real-time interactive media flows
share the link bandwidth and all flows reach to a steady state by
utilizing the link capacity in an optimum way. At these stage one of
the media flow is paused for a moment. This event will result in more
available bandwidth for the rest of the flows and as they are on a
shared link. When the paused media flow will resume it would no longer
have the same bandwidth share on the link. It has to make it's way
through the other existing flows in the link to achieve a fair share
of the link capacity. This test case is important specially for
real-time interactive media which consists of more than one media
flows and can pause/resume media flow at any point of time during the
session. This test case directly addresses the requirement number 5 in
<xref target="I-D.ietf-rmcat-cc-requirements"></xref>. One can think
it as a variation of test case defined in <xref
target="competing-rmcat-flow"></xref>. However, it is different as the
candidate algorithms can use different strategies to increase its
efficiency, for example the fairness, convergence time, reduce
oscillation etc, by capitalizing the fact that they have previous
information of the link.</t>
<t>To evaluate the performance of the candidate algorithms it is
expected to log enough information to visualize the following metrics
in addition to the metrics described in <xref target="EM"></xref> at a
fine enough time granularity: <list style="numbers">
<t>Flow level: <list style="letters">
<t>Variation in sending bit rate and goodput. Mainly observing
the frequency and magnitude of oscillations.</t>
</list></t>
</list></t>
<t>Testbed Topology: Same as test case defined in <xref
target="competing-rmcat-flow"></xref></t>
<t>Testbed attributes: The general description of the testbed
parameters are same as <xref target="competing-rmcat-flow"></xref>
with changes in the test specific setup as below-</t>
<t><list style="symbols">
<t>Other test specific setup: <list style="symbols">
<t>Media flow timeline: <list style="symbols">
<t>Flow ID: One (1)</t>
<t>Start time: 0s</t>
<t>Flow duration: 119s</t>
<t>Pause time: not required</t>
<t>Resume time: not required</t>
</list></t>
<t>Media flow timeline: <list style="symbols">
<t>Flow ID: Two (2)</t>
<t>Start time: 0s</t>
<t>Flow duration: 119s</t>
<t>Pause time: at 40s</t>
<t>Resume time: at 60s</t>
</list></t>
<t>Media flow timeline: <list style="symbols">
<t>Flow ID: Three (3)</t>
<t>Start time: 0s</t>
<t>Flow duration:119s</t>
<t>Pause time: not required</t>
<t>Resume time: not required</t>
</list></t>
</list></t>
</list></t>
</section>
</section>
<section title="Other potential test cases">
<t>It has been noticed that there are other interesting test cases
besides the basis test cases listed above. In many aspects, these
additional test cases can help to further evaluate the candidate
algorithm. They are listed as below.</t>
<section title="Explicit Congestion Notification Usage">
<t>This test case requires to run all the basic test cases with the
availability of Explicit Congestion Notification (ECN) <xref
target="RFC6679"></xref> feature enabled. The goal of this test is to
exhibit that the candidate algorithms does not fail when ECN signals
are available. With ECN signals enabled the algorithms are expected to
perform better than their delay based variants.</t>
</section>
<section title="Multiple Bottlenecks">
<t>In this test case one RMCAT flow, S1->R2 traverse a path with
multiple bottlenecks. As illustrated in <xref
target="fig-eval-topo-6-2"></xref>, the first flow (S1->R1)
competes with the second RMCAT flow (S2->R2) over the link between
A and B which is close to the sender side; again, that flow
(S1->R1) competes with the third RMCAT flow (S3->R3) over the
link between C and D which is close to the receiver side. The goal of
this test is to ensure that the candidate algorithms work properly in
the presence of multiple bottleneck links on the end to end path.</t>
<t>Expected behavior: the candidate algorithm is expected to achieve
full utilization at both bottleneck links without starving any of the
three RMCAT flows.</t>
<t><figure anchor="fig-eval-topo-6-2"
title="Testbed Topology for Multiple Bottlenecks">
<artwork><![CDATA[
Forward ---->
+---+ +---+ +---+ +---+
|S2 | |R2 | |S3 | |R3 |
+---+ +---+ +---+ +---+
| | | |
| | | |
+---+ +-----+ +-----+ +-----+ +-----+ +---+
|S1 |=======| A |------>| B |----->| C |---->| D |=======|R1 |
+---+ | |<------| |<-----| |<----| | +---+
+-----+ +-----+ +-----+ +-----+
1st 2nd
Bottleneck (A->B) Bottleneck (C->D)
<------ Backward
]]></artwork>
</figure></t>
<t>Testbed topology: Three media sources S1, S2, and S3 are connected
to respective destinations R1, R2, and R3. For all three flows the
media traffic is transported over the forward path and corresponding
feedback/control traffic is transported over the backward path.</t>
<t>Testbed attributes:</t>
<t><list style="symbols">
<t>Test duration: 120s</t>
<t>Path characteristics: <list style="symbols">
<t>Path capacity between A and B = 2Mbps.</t>
<t>Path capacity between B and C = 8Mbps.</t>
<t>Path capacity between C and D = 1.5Mbps.</t>
<t>One-Way propagation delay: <list style="numbers">
<t>Between S1 and R1 : 100ms</t>
<t>Between S2 and R2: 40ms</t>
<t>Between S3 and R3: 40ms</t>
</list></t>
</list></t>
<t>Application-related: <list style="symbols">
<t>Media Source: <list style="symbols">
<t>Media type: Video <list style="symbols">
<t>Media direction: Forward</t>
<t>Number of media sources: Three (3)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 0s.</t>
<t>End time: 119s.</t>
</list></t>
</list></t>
<t>Media type: Audio <list style="symbols">
<t>Media direction: Forward</t>
<t>Number of media sources: Three (3)</t>
<t>Media timeline: <list style="symbols">
<t>Start time: 0s.</t>
<t>End time: 119s.</t>
</list></t>
</list></t>
</list></t>
<t>Competing traffic: <list style="symbols">
<t>Number of sources : Zero (0)</t>
</list></t>
</list></t>
</list></t>
</section>
</section>
<section title="Wireless Access Links">
<section title="Cellular Network Specific Test Cases">
<t>Additional cellular network specific test cases are define in <xref
target="I-D.draft-sarker-rmcat-cellular-eval-test-cases"></xref></t>
<!--ZS: may be a link to another draft would be good enough-->
</section>
<!-- keep the comments out of the tags.-->
<section title="Wi-Fi Network Specific Test Cases">
<t>TBD</t>
<t>[Editor's Note: We should encourage people to come up with possible
WiFi Network specific test cases]</t>
<!--ZS: may be a link to another draft would be good enough-->
<!--The key network event those have impact on congestion control algorithm are-
? AP handover- causing interruption in communication, change in available bandwidth, delay and loss, restart of new session.
? Congested AP- causing race condition for medium access and leading to buffer overflow, loss and delay.
? Hidden node / exposed node problem- causing unnecessary error in transmission leading to low packet rate over radio and such.
However with modern RTS/CTS the situation is much improved.
It is analyzed how Wi-Fi is used then we can see there is basically three kind of access setup, for simplicity only two
endpoints are considered here, ? 1) all the endpoint connected over WiFi to same AP (no internet in between), 2) two endpoints
are connected over WiFi to two different access point (AP points may be connected over the Internet), 3) one endpoint is
connected over WiFi and another endpoint is connected to the Internet over any other access type than WiFi.
It is always encouraged to device test cases with real or simulated Wi-Fi access. However, considering a limited mobility
pattern and effect of the events in Wi.FI network a care full investigation may lead to devise a variation of general
test cases to evaluate the performance of congestion control algorithms. Hence this section is TBD.
-->
</section>
</section>
<section title="Security Considerations">
<t>Security issues have not been discussed in this memo.</t>
<!-- Congestion Collapse, Denial of Service -->
</section>
<section title="IANA Considerations">
<t>There are no IANA impacts in this memo.</t>
</section>
<section title="Acknowledgements">
<t>Much of this document is derived from previous work on congestion
control at the IETF.</t>
<t>The content and concepts within this document are a product of the
discussion carried out in the Design Team.</t>
</section>
</middle>
<back>
<references title="Normative References">
<!--&rfc2119;-->
<?rfc include='reference.RFC.6679.xml'?>
<!-- RTP related -->
&rfc3550;
&rfc3551;
&rfc3611;
&rfc4585;
&rfc5506;
<!--RMCAT related -->
&I-D.ietf-avtcore-rtp-circuit-breakers;
&I-D.ietf-rmcat-eval-criteria;
&I-D.ietf-rmcat-cc-requirements;
<reference anchor="I-D.draft-sarker-rmcat-cellular-eval-test-cases"
target="http://www.ietf.org/id/draft-sarker-rmcat-cellular-eval-test-cases-01.txt">
<front>
<title>Evaluation Test Cases for Interactive Real-Time Media over
Cellular Networks</title>
<author fullname="Zaheduzzaman Sarker" initials="Z" surname="Sarker"></author>
<author fullname="Ingemar Johansson" initials="I"
surname="Johansson"></author>
<date month="6" year="2014" />
</front>
</reference>
</references>
<references title="Informative References">
<!-- &I-D.ietf-rtcweb-use-cases-and-requirements; -->
<!-- &rfc5033; -->
<!-- CC Evaluation -->
<!-- &rfc5166; -->
<!-- CC Metrics -->
<!-- &rfc5681; -->
<!-- Standard TCP -->
<!-- <reference anchor="SA4-EVAL">
<front>
<title>LTE Link Level Throughput Data for SA4 Evaluation
Framework</title>
<author fullname="3GPP R1-081955" initials="3GPP"
surname="R1-081955">
<organization></organization>
</author>
<date month="5" year="2008" />
<abstract>
<t>In R1-081720, 3GPP SA4 has requested RAN1 and RAN2 for link
level throughput traces to be used in an evaluation framework they
are developing for dynamic video rate adaptation.</t>
</abstract>
</front>
<seriesInfo name="3GPP" value="R1-081955" />
<format octets="3459875"
target="http://www.3gpp.net/ftp/tsg_ran/WG1_RL1/TSGR1_53/Docs/R1-081955.zip"
type="ZIP" />
</reference> -->
<!-- <reference anchor="SA4-LR">
<front>
<title>Error Patterns for MBMS Streaming over UTRAN and
GERAN</title>
<author fullname="3GPP S4-050560" initials="3GPP"
surname="S4-050560">
<organization></organization>
</author>
<date month="5" year="2008" />
</front>
<seriesInfo name="3GPP" value="S4-050560" />
<format octets="335322"
target="http://www.3gpp.org/FTP/tsg_sa/WG4_CODEC/TSGS4_36/Docs/S4-050560.zip"
type="ZIP" />
</reference> -->
<reference anchor="xiph-seq">
<front>
<title>Video Test Media</title>
<author fullname="" initials="" surname="Xiph.org"></author>
<date month="" year="" />
</front>
<seriesInfo name="http://media.xiph.org/video/derf/" value="" />
</reference>
<reference anchor="HEVC-seq">
<front>
<title>Test Sequences</title>
<author fullname="" initials="" surname="HEVC"></author>
<date month="" year="" />
</front>
<seriesInfo name="http://www.netlab.tkk.fi/~varun/test_sequences/"
value="" />
</reference>
<!-- <reference anchor="TCP-eval-suite">
<front>
<title>Towards a Common TCP Evaluation Suite</title>
<author fullname="Andrew Lachlan" initials="A." surname="Lachlan"></author>
<author fullname="Cesar Marcondes" initials="C." surname="Marcondes"></author>
<author fullname="Sally Floyd" initials="S." surname="Floyd"></author>
<author fullname="Lawrence Dunn" initials="L." surname="Dunn"></author>
<author fullname="Romeric Guillier" initials="R." surname="Guillier"></author>
<author fullname="Wang Gang" initials="W." surname="Gang"></author>
<author fullname="Lars Eggert" initials="L." surname="Eggert"></author>
<author fullname="Sangtae Ha" initials="S." surname="Ha"></author>
<author fullname="Injong Rhee" initials="I." surname="Rhee"></author>
<date month="August" year="2008" />
</front>
<seriesInfo name="Proc. PFLDnet." value="2008" />
</reference> -->
</references>
<!-- <section anchor="App-cl" title="Change Log">
<t>Note to the RFC-Editor: please remove this section prior to
publication as an RFC.</t>
<section title="Changes in draft-singh-rmcat-cc-eval-01">
<t><list style="symbols">
<t></t>
</list></t>
</section>
</section>
-->
</back>
</rfc>
| PAFTECH AB 2003-2026 | 2026-04-24 02:38:07 |