draft-ietf-rmcat-wireless-tests-09.txt | draft-ietf-rmcat-wireless-tests-10.txt | |||
---|---|---|---|---|
Network Working Group Z. Sarker | Network Working Group Z. Sarker | |||
Internet-Draft I. Johansson | Internet-Draft Ericsson AB | |||
Intended status: Informational Ericsson AB | Intended status: Informational X. Zhu | |||
Expires: August 30, 2020 X. Zhu | Expires: September 10, 2020 J. Fu | |||
J. Fu | ||||
W. Tan | W. Tan | |||
Cisco Systems | Cisco Systems | |||
M. Ramalho | M. Ramalho | |||
AcousticComms | AcousticComms | |||
February 27, 2020 | March 9, 2020 | |||
Evaluation Test Cases for Interactive Real-Time Media over Wireless | Evaluation Test Cases for Interactive Real-Time Media over Wireless | |||
Networks | Networks | |||
draft-ietf-rmcat-wireless-tests-09 | draft-ietf-rmcat-wireless-tests-10 | |||
Abstract | Abstract | |||
The Real-time Transport Protocol (RTP) is a common transport choice | The Real-time Transport Protocol (RTP) is a common transport choice | |||
for interactive multimedia communication applications. The | for interactive multimedia communication applications. The | |||
performance of these applications typically depends on a well- | performance of these applications typically depends on a well- | |||
functioning congestion control algorithm. To ensure a seamless and | functioning congestion control algorithm. To ensure a seamless and | |||
robust user experience, a well-designed RTP-based congestion control | robust user experience, a well-designed RTP-based congestion control | |||
algorithm should work well across all access network types. This | algorithm should work well across all access network types. This | |||
document describes test cases for evaluating performances of | document describes test cases for evaluating performances of | |||
skipping to change at page 1, line 45 ¶ | skipping to change at page 1, line 44 ¶ | |||
Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
Task Force (IETF). Note that other groups may also distribute | Task Force (IETF). Note that other groups may also distribute | |||
working documents as Internet-Drafts. The list of current Internet- | working documents as Internet-Drafts. The list of current Internet- | |||
Drafts is at https://datatracker.ietf.org/drafts/current/. | Drafts is at https://datatracker.ietf.org/drafts/current/. | |||
Internet-Drafts are draft documents valid for a maximum of six months | Internet-Drafts are draft documents valid for a maximum of six months | |||
and may be updated, replaced, or obsoleted by other documents at any | and may be updated, replaced, or obsoleted by other documents at any | |||
time. It is inappropriate to use Internet-Drafts as reference | time. It is inappropriate to use Internet-Drafts as reference | |||
material or to cite them other than as "work in progress." | material or to cite them other than as "work in progress." | |||
This Internet-Draft will expire on August 30, 2020. | This Internet-Draft will expire on September 10, 2020. | |||
Copyright Notice | Copyright Notice | |||
Copyright (c) 2020 IETF Trust and the persons identified as the | Copyright (c) 2020 IETF Trust and the persons identified as the | |||
document authors. All rights reserved. | document authors. All rights reserved. | |||
This document is subject to BCP 78 and the IETF Trust's Legal | This document is subject to BCP 78 and the IETF Trust's Legal | |||
Provisions Relating to IETF Documents | Provisions Relating to IETF Documents | |||
(https://trustee.ietf.org/license-info) in effect on the date of | (https://trustee.ietf.org/license-info) in effect on the date of | |||
publication of this document. Please review these documents | publication of this document. Please review these documents | |||
carefully, as they describe your rights and restrictions with respect | carefully, as they describe your rights and restrictions with respect | |||
to this document. Code Components extracted from this document must | to this document. Code Components extracted from this document must | |||
include Simplified BSD License text as described in Section 4.e of | include Simplified BSD License text as described in Section 4.e of | |||
the Trust Legal Provisions and are provided without warranty as | the Trust Legal Provisions and are provided without warranty as | |||
described in the Simplified BSD License. | described in the Simplified BSD License. | |||
Table of Contents | Table of Contents | |||
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | |||
2. Terminologies . . . . . . . . . . . . . . . . . . . . . . . . 3 | 2. Cellular Network Specific Test Cases . . . . . . . . . . . . 3 | |||
3. Cellular Network Specific Test Cases . . . . . . . . . . . . 3 | 2.1. Varying Network Load . . . . . . . . . . . . . . . . . . 6 | |||
3.1. Varying Network Load . . . . . . . . . . . . . . . . . . 6 | 2.1.1. Network Connection . . . . . . . . . . . . . . . . . 6 | |||
3.1.1. Network Connection . . . . . . . . . . . . . . . . . 6 | 2.1.2. Simulation Setup . . . . . . . . . . . . . . . . . . 7 | |||
3.1.2. Simulation Setup . . . . . . . . . . . . . . . . . . 7 | 2.2. Bad Radio Coverage . . . . . . . . . . . . . . . . . . . 9 | |||
3.2. Bad Radio Coverage . . . . . . . . . . . . . . . . . . . 9 | 2.2.1. Network connection . . . . . . . . . . . . . . . . . 9 | |||
3.2.1. Network connection . . . . . . . . . . . . . . . . . 9 | 2.2.2. Simulation Setup . . . . . . . . . . . . . . . . . . 9 | |||
3.2.2. Simulation Setup . . . . . . . . . . . . . . . . . . 9 | 2.3. Desired Evaluation Metrics for cellular test cases . . . 10 | |||
3.3. Desired Evaluation Metrics for cellular test cases . . . 10 | 3. Wi-Fi Networks Specific Test Cases . . . . . . . . . . . . . 10 | |||
4. Wi-Fi Networks Specific Test Cases . . . . . . . . . . . . . 10 | 3.1. Bottleneck in Wired Network . . . . . . . . . . . . . . . 12 | |||
4.1. Bottleneck in Wired Network . . . . . . . . . . . . . . . 12 | 3.1.1. Network topology . . . . . . . . . . . . . . . . . . 12 | |||
4.1.1. Network topology . . . . . . . . . . . . . . . . . . 12 | 3.1.2. Test setup . . . . . . . . . . . . . . . . . . . . . 13 | |||
4.1.2. Test setup . . . . . . . . . . . . . . . . . . . . . 13 | 3.1.3. Typical test scenarios . . . . . . . . . . . . . . . 14 | |||
4.1.3. Typical test scenarios . . . . . . . . . . . . . . . 14 | 3.1.4. Expected behavior . . . . . . . . . . . . . . . . . . 15 | |||
4.1.4. Expected behavior . . . . . . . . . . . . . . . . . . 15 | 3.2. Bottleneck in Wi-Fi Network . . . . . . . . . . . . . . . 15 | |||
4.2. Bottleneck in Wi-Fi Network . . . . . . . . . . . . . . . 15 | 3.2.1. Network topology . . . . . . . . . . . . . . . . . . 15 | |||
4.2.1. Network topology . . . . . . . . . . . . . . . . . . 15 | 3.2.2. Test setup . . . . . . . . . . . . . . . . . . . . . 15 | |||
4.2.2. Test setup . . . . . . . . . . . . . . . . . . . . . 15 | 3.2.3. Typical test scenarios . . . . . . . . . . . . . . . 17 | |||
4.2.3. Typical test scenarios . . . . . . . . . . . . . . . 17 | 3.2.4. Expected behavior . . . . . . . . . . . . . . . . . . 18 | |||
4.2.4. Expected behavior . . . . . . . . . . . . . . . . . . 18 | 3.3. Other Potential Test Cases . . . . . . . . . . . . . . . 19 | |||
4.3. Other Potential Test Cases . . . . . . . . . . . . . . . 19 | 3.3.1. EDCA/WMM usage . . . . . . . . . . . . . . . . . . . 19 | |||
4.3.1. EDCA/WMM usage . . . . . . . . . . . . . . . . . . . 19 | 3.3.2. Effect of heterogeneous link rates . . . . . . . . . 19 | |||
4.3.2. Effect of heterogeneous link rates . . . . . . . . . 19 | 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20 | |||
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20 | 5. Security Considerations . . . . . . . . . . . . . . . . . . . 20 | |||
6. Security Considerations . . . . . . . . . . . . . . . . . . . 20 | 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20 | |||
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20 | 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 | |||
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 | 7.1. Normative References . . . . . . . . . . . . . . . . . . 20 | |||
8.1. Normative References . . . . . . . . . . . . . . . . . . 20 | 7.2. Informative References . . . . . . . . . . . . . . . . . 21 | |||
8.2. Informative References . . . . . . . . . . . . . . . . . 21 | ||||
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 | Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 | |||
1. Introduction | 1. Introduction | |||
Wireless networks (both cellular and Wi-Fi [IEEE802.11]) are an | Wireless networks (both cellular and Wi-Fi [IEEE802.11]) are an | |||
integral and increasingly more significant part of the Internet. | integral and increasingly more significant part of the Internet. | |||
Typical application scenarios for interactive multimedia | Typical application scenarios for interactive multimedia | |||
communication over wireless include from video conferencing calls in | communication over wireless include from video conferencing calls in | |||
a bus or train as well as live media streaming at home. It is well | a bus or train as well as live media streaming at home. It is well | |||
known that the characteristics and technical challenges for | known that the characteristics and technical challenges for | |||
supporting multimedia services over wireless are very different from | supporting multimedia services over wireless are very different from | |||
those of providing the same service over a wired network. Although | those of providing the same service over a wired network. Although | |||
the basic test cases as defined in [I-D.ietf-rmcat-eval-test] have | the basic test cases as defined in [I-D.ietf-rmcat-eval-test] have | |||
covered many common effects of network impairments for evaluating | covered many common effects of network impairments for evaluating | |||
RTP-based congestion control schemes, they remain to be tested over | RTP-based congestion control schemes, they remain to be tested over | |||
characteristics and dynamics unique to a given wireless environment. | characteristics and dynamics unique to a given wireless environment. | |||
For example, in cellular networks, the base station maintains | For example, in cellular networks, the base station maintains | |||
individual queues per radio bearer per user hence it leads to a | individual queues per radio bearer per user hence it leads to a | |||
different nature of interactions between traffic flows of different | different nature of interactions between traffic flows of different | |||
users. This contrasts with the wired network setting where traffic | users. This contrasts with a typical wired network setting where | |||
flows from all users share the same queue. Furthermore, user | traffic flows from all users share the same queue at the bottleneck. | |||
mobility patterns in a cellular network differ from those in a Wi-Fi | Furthermore, user mobility patterns in a cellular network differ from | |||
network. Therefore, it is important to evaluate the performance of | those in a Wi-Fi network. Therefore, it is important to evaluate the | |||
proposed candidate RTP-based congestion control solutions over | performance of proposed candidate RTP-based congestion control | |||
cellular mobile networks and over Wi-Fi networks respectively. | solutions over cellular mobile networks and over Wi-Fi networks | |||
respectively. | ||||
The draft [I-D.ietf-rmcat-eval-criteria] provides the guideline for | The draft [I-D.ietf-rmcat-eval-criteria] provides the guideline for | |||
evaluating candidate algorithms and recognizes the importance of | evaluating candidate algorithms and recognizes the importance of | |||
testing over wireless access networks. However, it does not describe | testing over wireless access networks. However, it does not describe | |||
any specific test cases for performance evaluation of candidate | any specific test cases for performance evaluation of candidate | |||
algorithms. This document describes test cases specifically | algorithms. This document describes test cases specifically | |||
targeting cellular and Wi-Fi networks. | targeting cellular and Wi-Fi networks. | |||
2. Terminologies | 2. Cellular Network Specific Test Cases | |||
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | ||||
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and | ||||
"OPTIONAL" in this document are to be interpreted as described in BCP | ||||
14 [RFC2119] [RFC8174] when, and only when, they appear in all | ||||
capitals, as shown here. | ||||
3. Cellular Network Specific Test Cases | ||||
A cellular environment is more complicated than its wireline | A cellular environment is more complicated than its wireline | |||
counterpart since it seeks to provide services in the context of | counterpart since it seeks to provide services in the context of | |||
variable available bandwidth, location dependencies and user | variable available bandwidth, location dependencies and user | |||
mobilities at different speeds. In a cellular network, the user may | mobilities at different speeds. In a cellular network, the user may | |||
reach the cell edge which may lead to a significant amount of | reach the cell edge which may lead to a significant amount of | |||
retransmissions to deliver the data from the base station to the | retransmissions to deliver the data from the base station to the | |||
destination and vice versa. These radio links will often act as a | destination and vice versa. These radio links will often act as a | |||
bottleneck for the rest of the network and will eventually lead to | bottleneck for the rest of the network and will eventually lead to | |||
excessive delays or packet drops. An efficient retransmission or | excessive delays or packet drops. An efficient retransmission or | |||
skipping to change at page 5, line 19 ¶ | skipping to change at page 5, line 10 ¶ | |||
cellular network needs to cope with a shared bottleneck link and | cellular network needs to cope with a shared bottleneck link and | |||
variable link capacity, events like handover, non-congestion related | variable link capacity, events like handover, non-congestion related | |||
loss, abrupt changes in bandwidth (both short term and long term) due | loss, abrupt changes in bandwidth (both short term and long term) due | |||
to handover, network load and bad radio coverage. Even though 3GPP | to handover, network load and bad radio coverage. Even though 3GPP | |||
has defined QoS bearers [QoS-3GPP] to ensure high-quality user | has defined QoS bearers [QoS-3GPP] to ensure high-quality user | |||
experience, it is still preferable for real-time applications to | experience, it is still preferable for real-time applications to | |||
behave in an adaptive manner. | behave in an adaptive manner. | |||
Different mobile operators deploy their own cellular networks with | Different mobile operators deploy their own cellular networks with | |||
their own set of network functionalities and policies. Usually, a | their own set of network functionalities and policies. Usually, a | |||
mobile operator network includes 2G, EDGE, 3G and 4G radio access | mobile operator network includes a range of radio access technologies | |||
technologies. Looking at the specifications of such radio | such as 3G and 4G/LTE. Looking at the specifications of such radio | |||
technologies it is evident that only the more recent radio | technologies it is evident that only the more recent radio | |||
technologies can support the high bandwidth requirements from real- | technologies can support the high bandwidth requirements from real- | |||
time interactive video applications. The future real-time | time interactive video applications. The future real-time | |||
interactive application will impose even greater demand on cellular | interactive application will impose even greater demand on cellular | |||
network performance which makes 4G (and beyond) radio technologies | network performance which makes 4G (and beyond) radio technologies | |||
more suitable for such genre of application. | more suitable for such genre of application. | |||
The key factors in defining test cases for cellular networks are: | The key factors in defining test cases for cellular networks are: | |||
o Shared and varying link capacity | o Shared and varying link capacity | |||
skipping to change at page 6, line 16 ¶ | skipping to change at page 6, line 8 ¶ | |||
that these networks are controlled by cellular operators and there | that these networks are controlled by cellular operators and there | |||
exist various amounts of competing traffic in the same cell(s). In | exist various amounts of competing traffic in the same cell(s). In | |||
practice, it is only in underground mines that one can carry out near | practice, it is only in underground mines that one can carry out near | |||
deterministic testing. Even there, it is not guaranteed either as | deterministic testing. Even there, it is not guaranteed either as | |||
workers in the mines may carry with them their personal mobile | workers in the mines may carry with them their personal mobile | |||
phones. Furthermore, the underground mining setting may not reflect | phones. Furthermore, the underground mining setting may not reflect | |||
typical usage patterns in an urban setting. We, therefore, recommend | typical usage patterns in an urban setting. We, therefore, recommend | |||
that a cellular network simulator is used for the test cases defined | that a cellular network simulator is used for the test cases defined | |||
in this document, for example -- the LTE simulator in [NS-3]. | in this document, for example -- the LTE simulator in [NS-3]. | |||
3.1. Varying Network Load | 2.1. Varying Network Load | |||
The goal of this test is to evaluate the performance of the candidate | The goal of this test is to evaluate the performance of the candidate | |||
congestion control algorithm under varying network load. The network | congestion control algorithm under varying network load. The network | |||
load variation is created by adding and removing network users a.k.a. | load variation is created by adding and removing network users a.k.a. | |||
User Equipments (UEs) during the simulation. In this test case, each | User Equipments (UEs) during the simulation. In this test case, each | |||
user/UE in the media session is an endpoint following RTP-based | user/UE in the media session is an endpoint following RTP-based | |||
congestion control. User arrivals follow a Poisson distribution | congestion control. User arrivals follow a Poisson distribution | |||
proportional to the length of the call, to keep the number of users | proportional to the length of the call, to keep the number of users | |||
per cell fairly constant during the evaluation period. At the | per cell fairly constant during the evaluation period. At the | |||
beginning of the simulation, there should be enough time to warm-up | beginning of the simulation, there should be enough time to warm-up | |||
the network. This is to avoid running the evaluation in an empty | the network. This is to avoid running the evaluation in an empty | |||
network where network nodes are having empty buffers, low | network where network nodes are having empty buffers, low | |||
interference at the beginning of the simulation. This network | interference at the beginning of the simulation. This network | |||
initialization period should be excluded from the evaluation period. | initialization period should be excluded from the evaluation period. | |||
Typically, the evaluation period starts 30 seconds after test | ||||
initialization. | ||||
This test case also includes user mobility and some competing | This test case also includes user mobility and some competing | |||
traffic. The latter includes both the same types of flows (with same | traffic. The latter includes both the same types of flows (with same | |||
adaptation algorithms) and different types of flows (with different | adaptation algorithms) and different types of flows (with different | |||
services and congestion control schemes). The investigated | services and congestion control schemes). The investigated | |||
congestion control algorithms should show maximum possible network | congestion control algorithms should show maximum possible network | |||
utilization and stability in terms of rate variations, lowest | utilization and stability in terms of rate variations, lowest | |||
possible end to end frame latency, network latency and Packet Loss | possible end to end frame latency, network latency and Packet Loss | |||
Rate (PLR) at different cell load level. | Rate (PLR) at different cell load level. | |||
3.1.1. Network Connection | 2.1.1. Network Connection | |||
Each mobile user is connected to a fixed user. The connection | Each mobile user is connected to a fixed user. The connection | |||
between the mobile user and fixed user consists of a cellular radio | between the mobile user and fixed user consists of a cellular radio | |||
access, an Evolved Packet Core (EPC) and an Internet connection. The | access, an Evolved Packet Core (EPC) and an Internet connection. The | |||
mobile user is connected to the EPC using cellular radio access | mobile user is connected to the EPC using cellular radio access | |||
technology which is further connected to the Internet. At the other | technology which is further connected to the Internet. At the other | |||
end, the fixed user is connected to the Internet via wired connection | end, the fixed user is connected to the Internet via wired connection | |||
with sufficiently high bandwidth, for instance, 10 Gbps, so that the | with sufficiently high bandwidth, for instance, 10 Gbps, so that the | |||
system bottleneck is on the cellular radio access interface. The | system bottleneck is on the cellular radio access interface. The | |||
wired connection to in this setup does not introduce any network | wired connection to in this setup does not introduce any network | |||
skipping to change at page 7, line 25 ¶ | skipping to change at page 7, line 19 ¶ | |||
++-+ ((o)) | ++-+ ((o)) | |||
| | / \ +-------+ +------+ +---+ | | | / \ +-------+ +------+ +---+ | |||
+--+ / \----+ +-----+ +----+ | | +--+ / \----+ +-----+ +----+ | | |||
/ \ +-------+ +------+ +---+ | / \ +-------+ +------+ +---+ | |||
UE BS EPC Internet fixed | UE BS EPC Internet fixed | |||
<--------------------------+ | <--------------------------+ | |||
downlink | downlink | |||
Figure 1: Simulation Topology | Figure 1: Simulation Topology | |||
3.1.2. Simulation Setup | 2.1.2. Simulation Setup | |||
The values enclosed within "[ ]" for the following simulation | The values enclosed within "[ ]" for the following simulation | |||
attributes follow the same notion as in [I-D.ietf-rmcat-eval-test]. | attributes follow the same notion as in [I-D.ietf-rmcat-eval-test]. | |||
The desired simulation setup is as follows -- | The desired simulation setup is as follows -- | |||
1. Radio environment: | 1. Radio environment: | |||
A. Deployment and propagation model: 3GPP case 1 (see | A. Deployment and propagation model: 3GPP case 1 (see | |||
[HO-deploy-3GPP]) | [HO-deploy-3GPP]) | |||
B. Antenna: Multiple-Input and Multiple-Output (MIMO), [2D, 3D] | B. Antenna: Multiple-Input and Multiple-Output (MIMO), 2D or 3D | |||
antenna pattern. | ||||
C. Mobility: [3km/h, 30km/h] | C. Mobility: [3km/h, 30km/h] | |||
D. Transmission bandwidth: 10Mhz | D. Transmission bandwidth: 10MHz | |||
E. Number of cells: multi-cell deployment (3 Cells per Base | E. Number of cells: multi-cell deployment (3 Cells per Base | |||
Station (BS) * 7 BS) = 21 cells | Station (BS) * 7 BS) = 21 cells | |||
F. Cell radius: 166.666 Meters | F. Cell radius: 166.666 Meters | |||
G. Scheduler: Proportional fair with no priority | G. Scheduler: Proportional fair with no priority | |||
H. Bearer: Default bearer for all traffic. | H. Bearer: Default bearer for all traffic. | |||
skipping to change at page 9, line 12 ¶ | skipping to change at page 9, line 5 ¶ | |||
8. Other traffic models: | 8. Other traffic models: | |||
* Downlink simulation: Maximum of 4Mbps/cell (web browsing or | * Downlink simulation: Maximum of 4Mbps/cell (web browsing or | |||
FTP traffic following default TCP congestion control | FTP traffic following default TCP congestion control | |||
[RFC5681]) | [RFC5681]) | |||
* Unlink simulation: Maximum of 2Mbps/cell (web browsing or FTP | * Unlink simulation: Maximum of 2Mbps/cell (web browsing or FTP | |||
traffic following default TCP congestion control [RFC5681]) | traffic following default TCP congestion control [RFC5681]) | |||
3.2. Bad Radio Coverage | 2.2. Bad Radio Coverage | |||
The goal of this test is to evaluate the performance of candidate | The goal of this test is to evaluate the performance of candidate | |||
congestion control algorithm when users visit part of the network | congestion control algorithm when users visit part of the network | |||
with bad radio coverage. The scenario is created by using a larger | with bad radio coverage. The scenario is created by using a larger | |||
cell radius than that in the previous test case. In this test case, | cell radius than that in the previous test case. In this test case, | |||
each user/UE in the media session is an RMCAT compliant endpoint. | each user/UE in the media session is an endpoint following RTP-based | |||
User arrivals follow a Poisson distribution proportional to the | congestion control. User arrivals follow a Poisson distribution | |||
length of the call, to keep the number of users per cell fairly | proportional to the length of the call, to keep the number of users | |||
constant during the evaluation period. At the beginning of the | per cell fairly constant during the evaluation period. At the | |||
simulation, there should be enough amount of time to warm-up the | beginning of the simulation, there should be enough amount of time to | |||
network. This is to avoid running the evaluation in an empty network | warm-up the network. This is to avoid running the evaluation in an | |||
where network nodes are having empty buffers, low interference at the | empty network where network nodes are having empty buffers, low | |||
beginning of the simulation. This network initialization period | interference at the beginning of the simulation. This network | |||
should be excluded from the evaluation period. | initialization period should be excluded from the evaluation period. | |||
Typically, the evaluation period starts 30 seconds after test | ||||
initialization. | ||||
This test case also includes user mobility and some competing | This test case also includes user mobility and some competing | |||
traffic. The latter includes the same kind of flows (with same | traffic. The latter includes the same kind of flows (with same | |||
adaptation algorithms). The investigated congestion control | adaptation algorithms). The investigated congestion control | |||
algorithms should result in maximum possible network utilization and | algorithms should result in maximum possible network utilization and | |||
stability in terms of rate variations, lowest possible end to end | stability in terms of rate variations, lowest possible end to end | |||
frame latency, network latency and Packet Loss Rate (PLR) at | frame latency, network latency and Packet Loss Rate (PLR) at | |||
different cell load levels. | different cell load levels. | |||
3.2.1. Network connection | 2.2.1. Network connection | |||
Same as defined in Section 3.1.1 | Same as defined in Section 2.1.1 | |||
3.2.2. Simulation Setup | 2.2.2. Simulation Setup | |||
The desired simulation setup is the same as the Varying Network Load | The desired simulation setup is the same as the Varying Network Load | |||
test case defined in Section 3.1 except the following changes: | test case defined in Section 2.1 except the following changes: | |||
1. Radio environment: Same as defined in Section 3.1.2 except the | 1. Radio environment: Same as defined in Section 2.1.2 except the | |||
following: | following: | |||
A. Deployment and propagation model: 3GPP case 3 (see | A. Deployment and propagation model: 3GPP case 3 (see | |||
[HO-deploy-3GPP]) | [HO-deploy-3GPP]) | |||
B. Cell radius: 577.3333 Meters | B. Cell radius: 577.3333 Meters | |||
C. Mobility: 3km/h | C. Mobility: 3km/h | |||
2. User intensity = {0.7, 1.4, 2.1, 2.8, 3.5, 4.2, 4.9, 5.6, 6.3, | 2. User intensity = {0.7, 1.4, 2.1, 2.8, 3.5, 4.2, 4.9, 5.6, 6.3, | |||
7.0} | 7.0} | |||
3. Media traffic model: Same as defined in Section 3.1.2 | 3. Media traffic model: Same as defined in Section 2.1.2 | |||
4. Other traffic models: | 4. Other traffic models: | |||
* Downlink simulation: Maximum of 2Mbps/cell (web browsing or | * Downlink simulation: Maximum of 2Mbps/cell (web browsing or | |||
FTP traffic following default TCP congestion control | FTP traffic following default TCP congestion control | |||
[RFC5681]) | [RFC5681]) | |||
* Unlink simulation: Maximum of 1Mbps/cell (web browsing or FTP | * Unlink simulation: Maximum of 1Mbps/cell (web browsing or FTP | |||
traffic following default TCP congestion control [RFC5681]) | traffic following default TCP congestion control [RFC5681]) | |||
3.3. Desired Evaluation Metrics for cellular test cases | 2.3. Desired Evaluation Metrics for cellular test cases | |||
The evaluation criteria document [I-D.ietf-rmcat-eval-criteria] | The evaluation criteria document [I-D.ietf-rmcat-eval-criteria] | |||
defines the metrics to be used to evaluate candidate algorithms. | defines the metrics to be used to evaluate candidate algorithms. | |||
Considering the nature and distinction of cellular networks we | Considering the nature and distinction of cellular networks we | |||
recommend that at least the following metrics be used to evaluate the | recommend that at least the following metrics be used to evaluate the | |||
performance of the candidate algorithms: | performance of the candidate algorithms: | |||
o Average cell throughput (for all cells), shows cell utilizations. | o Average cell throughput (for all cells), shows cell utilizations. | |||
o Application sending and receiving bitrate, goodput. | o Application sending and receiving bitrate, goodput. | |||
o Packet Loss Rate (PLR). | o Packet Loss Rate (PLR). | |||
o End-to-end Media frame delay. For video, this means the delay | o End-to-end Media frame delay. For video, this means the delay | |||
from capture to display. | from capture to display. | |||
o Transport delay. | o Transport delay. | |||
o Algorithm stability in terms of rate variation. | o Algorithm stability in terms of rate variation. | |||
4. Wi-Fi Networks Specific Test Cases | 3. Wi-Fi Networks Specific Test Cases | |||
Given the prevalence of Internet access links over Wi-Fi, it is | Given the prevalence of Internet access links over Wi-Fi, it is | |||
important to evaluate candidate RTP-based congestion control | important to evaluate candidate RTP-based congestion control | |||
solutions over test cases that include Wi-Fi access links. Such | solutions over test cases that include Wi-Fi access links. Such | |||
evaluations should highlight the inherently different characteristics | evaluations should highlight the inherently different characteristics | |||
of Wi-Fi networks in contrast to their wired counterparts: | of Wi-Fi networks in contrast to their wired counterparts: | |||
o The wireless radio channel is subject to interference from nearby | o The wireless radio channel is subject to interference from nearby | |||
transmitters, multipath fading, and shadowing. These effects lead | transmitters, multipath fading, and shadowing. These effects lead | |||
to fluctuations in the link throughput and sometimes an error- | to fluctuations in the link throughput and sometimes an error- | |||
skipping to change at page 12, line 31 ¶ | skipping to change at page 12, line 28 ¶ | |||
both scenarios separately. The same set of performance metrics as in | both scenarios separately. The same set of performance metrics as in | |||
[I-D.ietf-rmcat-eval-test]) should be collected for each test case. | [I-D.ietf-rmcat-eval-test]) should be collected for each test case. | |||
We recommend to carry out the test cases as defined in this document | We recommend to carry out the test cases as defined in this document | |||
using a simulator, such as [NS-2] or [NS-3]. When feasible, it is | using a simulator, such as [NS-2] or [NS-3]. When feasible, it is | |||
encouraged to perform testbed-based evaluations using Wi-Fi access | encouraged to perform testbed-based evaluations using Wi-Fi access | |||
points and endpoints running up-to-date IEEE 802.11 protocols, such | points and endpoints running up-to-date IEEE 802.11 protocols, such | |||
as 802.11ac and the emerging Wi-Fi 6, so as to verify the viability | as 802.11ac and the emerging Wi-Fi 6, so as to verify the viability | |||
of the candidate schemes. | of the candidate schemes. | |||
4.1. Bottleneck in Wired Network | 3.1. Bottleneck in Wired Network | |||
The test scenarios below are intended to mimic the setup of video | The test scenarios below are intended to mimic the setup of video | |||
conferencing over Wi-Fi connections from the home. Typically, the | conferencing over Wi-Fi connections from the home. Typically, the | |||
Wi-Fi home network is not congested and the bottleneck is present | Wi-Fi home network is not congested and the bottleneck is present | |||
over the wired home access link. Although it is expected that test | over the wired home access link. Although it is expected that test | |||
evaluation results from this section are similar to those as in | evaluation results from this section are similar to those as in | |||
[I-D.ietf-rmcat-eval-test], it is still worthwhile to run through | [I-D.ietf-rmcat-eval-test], it is still worthwhile to run through | |||
these tests as sanity checks. | these tests as sanity checks. | |||
4.1.1. Network topology | 3.1.1. Network topology | |||
Figure 2 shows the network topology of Wi-Fi test cases. The test | Figure 2 shows the network topology of Wi-Fi test cases. The test | |||
contains multiple mobile nodes (MNs) connected to a common Wi-Fi | contains multiple mobile nodes (MNs) connected to a common Wi-Fi | |||
access point (AP) and their corresponding wired clients on fixed | access point (AP) and their corresponding wired clients on fixed | |||
nodes (FNs). Each connection carries either a RTP-based media flow | nodes (FNs). Each connection carries either a RTP-based media flow | |||
or a TCP traffic flow. Directions of the flows can be uplink (i.e., | or a TCP traffic flow. Directions of the flows can be uplink (i.e., | |||
from mobile nodes to fixed nodes), downlink (i.e., from fixed nodes | from mobile nodes to fixed nodes), downlink (i.e., from fixed nodes | |||
to mobile nodes), or bi-directional. The total number of | to mobile nodes), or bi-directional. The total number of | |||
uplink/downlink/bi-directional flows for RTP-based media traffic and | uplink/downlink/bi-directional flows for RTP-based media traffic and | |||
TCP traffic are denoted as N and M, respectively. | TCP traffic are denoted as N and M, respectively. | |||
skipping to change at page 13, line 31 ¶ | skipping to change at page 13, line 31 ¶ | |||
. )) \\ . | . )) \\ . | |||
. )) \\ . | . )) \\ . | |||
+----------+ )) \\ +----------+ | +----------+ )) \\ +----------+ | |||
| MN_tcp_M |))) \=====| FN_tcp_M | | | MN_tcp_M |))) \=====| FN_tcp_M | | |||
+----------+ +----------+ | +----------+ +----------+ | |||
+<-----------------+ | +<-----------------+ | |||
Downlink | Downlink | |||
Figure 2: Network topology for Wi-Fi test cases | Figure 2: Network topology for Wi-Fi test cases | |||
4.1.2. Test setup | 3.1.2. Test setup | |||
o Test duration: 120s | o Test duration: 120s | |||
o Wi-Fi network characteristics: | o Wi-Fi network characteristics: | |||
* Radio propagation model: Log-distance path loss propagation | * Radio propagation model: Log-distance path loss propagation | |||
model (see [NS3WiFi]) | model (see [NS3WiFi]) | |||
* PHY- and MAC-layer configuration: IEEE 802.11n | * PHY- and MAC-layer configuration: IEEE 802.11n | |||
skipping to change at page 14, line 15 ¶ | skipping to change at page 14, line 15 ¶ | |||
* Bottleneck queue size: 300ms. | * Bottleneck queue size: 300ms. | |||
* Path loss ratio: 0%. | * Path loss ratio: 0%. | |||
o Application characteristics: | o Application characteristics: | |||
* Media Traffic: | * Media Traffic: | |||
+ Media type: Video | + Media type: Video | |||
+ Media direction: See Section 4.1.3 | + Media direction: See Section 3.1.3 | |||
+ Number of media sources (N): See Section 4.1.3 | + Number of media sources (N): See Section 3.1.3 | |||
+ Media timeline: | + Media timeline: | |||
- Start time: 0s. | - Start time: 0s. | |||
- End time: 119s. | - End time: 119s. | |||
* Competing traffic: | * Competing traffic: | |||
+ Type of sources: long-lived TCP or CBR over UDP | + Type of sources: long-lived TCP or CBR over UDP | |||
+ Traffic direction: See Section 4.1.3 | + Traffic direction: See Section 3.1.3 | |||
+ Number of sources (M): See Section 4.1.3 | + Number of sources (M): See Section 3.1.3 | |||
+ Congestion control: Default TCP congestion control [RFC5681] | + Congestion control: Default TCP congestion control [RFC5681] | |||
or constant-bit-rate (CBR) traffic over UDP. | or constant-bit-rate (CBR) traffic over UDP. | |||
+ Traffic timeline: See Section 4.1.3 | + Traffic timeline: See Section 3.1.3 | |||
4.1.3. Typical test scenarios | 3.1.3. Typical test scenarios | |||
o Single uplink RTP-based media flow: N=1 with uplink direction and | o Single uplink RTP-based media flow: N=1 with uplink direction and | |||
M=0. | M=0. | |||
o One pair of bi-directional RTP-based media flows: N=2 (i.e., one | o One pair of bi-directional RTP-based media flows: N=2 (i.e., one | |||
uplink flow and one downlink flow); M=0. | uplink flow and one downlink flow); M=0. | |||
o One pair of bi-directional RTP-based media flows: N=2; one uplink | o One pair of bi-directional RTP-based media flows: N=2; one uplink | |||
on-off CBR flow over UDP: M=1 (uplink). The CBR flow has ON time | on-off CBR flow over UDP: M=1 (uplink). The CBR flow has ON time | |||
at t=0s-60s and OFF time at t=60s-119s. | at t=0s-60s and OFF time at t=60s-119s. | |||
o One pair of bi-directional RTP-based media flows: N=2; one uplink | o One pair of bi-directional RTP-based media flows: N=2; one uplink | |||
off-on CBR flow over UDP: M=1 (uplink). The CBR flow has OFF time | off-on CBR flow over UDP: M=1 (uplink). The CBR flow has OFF time | |||
at t=0s-60s and ON time at t=60s-119s. | at t=0s-60s and ON time at t=60s-119s. | |||
o One RTP-based media flow competing against one long-live TCP flow | o One RTP-based media flow competing against one long-live TCP flow | |||
in the uplink direction: N=1 (uplink) and M = 1(uplink). The TCP | in the uplink direction: N=1 (uplink) and M = 1(uplink). The TCP | |||
flow has start time at t=0s and end time at t=119s. | flow has start time at t=0s and end time at t=119s. | |||
4.1.4. Expected behavior | 3.1.4. Expected behavior | |||
o Single uplink RTP-based media flow: the candidate algorithm is | o Single uplink RTP-based media flow: the candidate algorithm is | |||
expected to detect the path capacity constraint, to converge to | expected to detect the path capacity constraint, to converge to | |||
the bottleneck link capacity, and to adapt the flow to avoid | the bottleneck link capacity, and to adapt the flow to avoid | |||
unwanted oscillations when the sending bit rate is approaching the | unwanted oscillations when the sending bit rate is approaching the | |||
bottleneck link capacity. No excessive oscillations in the media | bottleneck link capacity. No excessive oscillations in the media | |||
rate should be present. | rate should be present. | |||
o Bi-directional RTP-based media flows: the candidate algorithm is | o Bi-directional RTP-based media flows: the candidate algorithm is | |||
expected to converge to the bottleneck capacity of the wired path | expected to converge to the bottleneck capacity of the wired path | |||
in both directions despite the presence of measurement noise over | in both directions despite the presence of measurement noise over | |||
the Wi-Fi connection. In the presence of background TCP or CBR | the Wi-Fi connection. In the presence of background TCP or CBR | |||
over UDP traffic, the rate of RTP-based media flows should adapt | over UDP traffic, the rate of RTP-based media flows should adapt | |||
promptly to the arrival and departure of background traffic flows. | promptly to the arrival and departure of background traffic flows. | |||
o One RTP-based media flow competing with long-live TCP flow in the | o One RTP-based media flow competing with long-live TCP flow in the | |||
uplink direction: the candidate algorithm is expected to avoid | uplink direction: the candidate algorithm is expected to avoid | |||
congestion collapse and to stabilize at a fair share of the | congestion collapse and to stabilize at a fair share of the | |||
bottleneck link capacity. | bottleneck link capacity. | |||
4.2. Bottleneck in Wi-Fi Network | 3.2. Bottleneck in Wi-Fi Network | |||
The test cases in this section assume that the wired segment along | The test cases in this section assume that the wired segment along | |||
the media path is well-provisioned whereas the bottleneck exists over | the media path is well-provisioned whereas the bottleneck exists over | |||
the Wi-Fi access network. This is to mimic the application scenarios | the Wi-Fi access network. This is to mimic the application scenarios | |||
typically encountered by users in an enterprise environment or at a | typically encountered by users in an enterprise environment or at a | |||
coffee house. | coffee house. | |||
4.2.1. Network topology | 3.2.1. Network topology | |||
Same as defined in Section 4.1.1 | Same as defined in Section 3.1.1 | |||
4.2.2. Test setup | 3.2.2. Test setup | |||
o Test duration: 120s | o Test duration: 120s | |||
o Wi-Fi network characteristics: | o Wi-Fi network characteristics: | |||
* Radio propagation model: Log-distance path loss propagation | * Radio propagation model: Log-distance path loss propagation | |||
model (see [NS3WiFi]) | model (see [NS3WiFi]) | |||
* PHY- and MAC-layer configuration: IEEE 802.11n | * PHY- and MAC-layer configuration: IEEE 802.11n | |||
* MCS Index at 11: 16-QAM 1/2, Raw Data Rate at 52Mbps | * MCS Index at 11: 16-QAM 1/2, Raw Data Rate at 52Mbps | |||
skipping to change at page 16, line 26 ¶ | skipping to change at page 16, line 26 ¶ | |||
* Bottleneck queue size: 300ms. | * Bottleneck queue size: 300ms. | |||
* Path loss ratio: 0%. | * Path loss ratio: 0%. | |||
o Application characteristics: | o Application characteristics: | |||
* Media Traffic: | * Media Traffic: | |||
+ Media type: Video | + Media type: Video | |||
+ Media direction: See Section 4.2.3. | + Media direction: See Section 3.2.3. | |||
+ Number of media sources (N): See Section 4.2.3. | + Number of media sources (N): See Section 3.2.3. | |||
+ Media timeline: | + Media timeline: | |||
- Start time: 0s. | - Start time: 0s. | |||
- End time: 119s. | - End time: 119s. | |||
* Competing traffic: | * Competing traffic: | |||
+ Type of sources: long-lived TCP or CBR over UDP. | + Type of sources: long-lived TCP or CBR over UDP. | |||
+ Number of sources (M): See Section 4.2.3. | + Number of sources (M): See Section 3.2.3. | |||
+ Traffic direction: See Section 4.2.3. | + Traffic direction: See Section 3.2.3. | |||
+ Congestion control: Default TCP congestion control [RFC5681] | + Congestion control: Default TCP congestion control [RFC5681] | |||
or constant-bit-rate (CBR) traffic over UDP. | or constant-bit-rate (CBR) traffic over UDP. | |||
+ Traffic timeline: See Section 4.2.3. | + Traffic timeline: See Section 3.2.3. | |||
4.2.3. Typical test scenarios | 3.2.3. Typical test scenarios | |||
This section describes a few test scenarios that are deemed as | This section describes a few test scenarios that are deemed as | |||
important for understanding the behavior of a candidate RTP-based | important for understanding the behavior of a candidate RTP-based | |||
congestion control scheme over a Wi-Fi network. | congestion control scheme over a Wi-Fi network. | |||
a. Multiple RTP-based media flows sharing the wireless downlink: | a. Multiple RTP-based media flows sharing the wireless downlink: | |||
N=16 (all downlink); M = 0. This test case is for studying the | N=16 (all downlink); M = 0. This test case is for studying the | |||
impact of contention on the multiple concurrent media flows. For | impact of contention on the multiple concurrent media flows. For | |||
an 802.11n network, given the MCS Index of 11 and the | an 802.11n network, given the MCS Index of 11 and the | |||
corresponding link rate of 52Mbps, the total application-layer | corresponding link rate of 52Mbps, the total application-layer | |||
throughput (assuming reasonable distance, low interference and | throughput (assuming reasonable distance, low interference and | |||
infrequent contentions caused by competing streams) is around | infrequent contentions caused by competing streams) is around | |||
20Mbps. A total of N=16 RTP-based media flows (with a maximum | 20Mbps. A total of N=16 RTP-based media flows (with a maximum | |||
rate of 1.5Mbps each) are expected to saturate the wireless | rate of 1.5Mbps each) are expected to saturate the wireless | |||
interface in this experiment. Evaluation of a given candidate | interface in this experiment. Evaluation of a given candidate | |||
scheme should focus on whether the downlink media flows can | scheme should focus on whether the downlink media flows can | |||
stabilize at a fair share of the total application-layer | stabilize at a fair share of the total application-layer | |||
throughput. | throughput. | |||
b. Multiple RTP-based media flows sharing the wireless uplink:N = 16 | b. Multiple RTP-based media flows sharing the wireless uplink: N = | |||
(all downlink); M = 0. When multiple clients attempt to transmit | 16 (all uplink); M = 0. When multiple clients attempt to | |||
media packets uplink over the Wi-Fi network, they introduce more | transmit media packets uplink over the Wi-Fi network, they | |||
frequent contentions and potential collisions. Per-flow | introduce more frequent contentions and potential collisions. | |||
throughput is expected to be lower than that in the previous | Per-flow throughput is expected to be lower than that in the | |||
downlink-only scenario. Evaluation of a given candidate scheme | previous downlink-only scenario. Evaluation of a given candidate | |||
should focus on whether the uplink flows can stabilize at a fair | scheme should focus on whether the uplink flows can stabilize at | |||
share of the total application-layer throughput. | a fair share of the total application-layer throughput. | |||
c. Multiple bi-directional RTP-based media flows: N = 16 (8 uplink | c. Multiple bi-directional RTP-based media flows: N = 16 (8 uplink | |||
and 8 downlink); M = 0. The goal of this test is to evaluate the | and 8 downlink); M = 0. The goal of this test is to evaluate the | |||
performance of the candidate scheme in terms of bandwidth | performance of the candidate scheme in terms of bandwidth | |||
fairness between uplink and downlink flows. | fairness between uplink and downlink flows. | |||
d. Multiple bi-directional RTP-based media flows with on-off CBR | d. Multiple bi-directional RTP-based media flows with on-off CBR | |||
traffic over UDP: N = 16 (8 uplink and 8 downlink); M = 5 | traffic over UDP: N = 16 (8 uplink and 8 downlink); M = 5 | |||
(uplink). The goal of this test is to evaluate the adaptation | (uplink). The goal of this test is to evaluate the adaptation | |||
behavior of the candidate scheme when its available bandwidth | behavior of the candidate scheme when its available bandwidth | |||
skipping to change at page 18, line 24 ¶ | skipping to change at page 18, line 24 ¶ | |||
g. Varying number of RTP-based media flows: A series of tests can be | g. Varying number of RTP-based media flows: A series of tests can be | |||
carried out for the above test cases with different values of N, | carried out for the above test cases with different values of N, | |||
e.g., N = [4, 8, 12, 16, 20]. The goal of this test is to | e.g., N = [4, 8, 12, 16, 20]. The goal of this test is to | |||
evaluate how a candidate scheme responds to varying traffic load/ | evaluate how a candidate scheme responds to varying traffic load/ | |||
demand over a congested Wi-Fi network. The start times of the | demand over a congested Wi-Fi network. The start times of the | |||
media flows are randomly distributes within a window of t=0-10s; | media flows are randomly distributes within a window of t=0-10s; | |||
their end times are randomly distributed within a window of | their end times are randomly distributed within a window of | |||
t=110-120s. | t=110-120s. | |||
4.2.4. Expected behavior | 3.2.4. Expected behavior | |||
o Multiple downlink RTP-based media flows: each media flow is | o Multiple downlink RTP-based media flows: each media flow is | |||
expected to get its fair share of the total bottleneck link | expected to get its fair share of the total bottleneck link | |||
bandwidth. Overall bandwidth usage should not be significantly | bandwidth. Overall bandwidth usage should not be significantly | |||
lower than that experienced by the same number of concurrent | lower than that experienced by the same number of concurrent | |||
downlink TCP flows. In other words, the behavior of multiple | downlink TCP flows. In other words, the behavior of multiple | |||
concurrent TCP flows will be used as a performance benchmark for | concurrent TCP flows will be used as a performance benchmark for | |||
this test scenario. The end-to-end delay and packet loss ratio | this test scenario. The end-to-end delay and packet loss ratio | |||
experienced by each flow should be within an acceptable range for | experienced by each flow should be within an acceptable range for | |||
real-time multimedia applications. | real-time multimedia applications. | |||
skipping to change at page 19, line 23 ¶ | skipping to change at page 19, line 23 ¶ | |||
o Varying number of bi-directional RTP-based media flows: the test | o Varying number of bi-directional RTP-based media flows: the test | |||
results for varying values of N -- while keeping all other | results for varying values of N -- while keeping all other | |||
parameters constant -- is expected to show steady and stable per- | parameters constant -- is expected to show steady and stable per- | |||
flow throughput for each value of N. The average throughput of | flow throughput for each value of N. The average throughput of | |||
all media flows is expected to stay constant around the maximum | all media flows is expected to stay constant around the maximum | |||
rate when N is small, then gradually decrease with increasing | rate when N is small, then gradually decrease with increasing | |||
value of N till it reaches the minimum allowed rate, beyond which | value of N till it reaches the minimum allowed rate, beyond which | |||
the offered load to the Wi-Fi network exceeds its capacity (i.e., | the offered load to the Wi-Fi network exceeds its capacity (i.e., | |||
with a very large value of N). | with a very large value of N). | |||
4.3. Other Potential Test Cases | 3.3. Other Potential Test Cases | |||
4.3.1. EDCA/WMM usage | 3.3.1. EDCA/WMM usage | |||
The EDCA/WMM mechanism defines prioritized QoS for four traffic | The EDCA/WMM mechanism defines prioritized QoS for four traffic | |||
classes (or Access Categories). RTP-based real-time media flows | classes (or Access Categories). RTP-based real-time media flows | |||
should achieve better performance in terms of lower delay and fewer | should achieve better performance in terms of lower delay and fewer | |||
packet losses with EDCA/WMM enabled when competing against non- | packet losses with EDCA/WMM enabled when competing against non- | |||
interactive background traffic such as file transfers. When most of | interactive background traffic such as file transfers. When most of | |||
the traffic over Wi-Fi is dominated by media, however, turning on WMM | the traffic over Wi-Fi is dominated by media, however, turning on WMM | |||
may degrade performance since all media flows now attempt to access | may degrade performance since all media flows now attempt to access | |||
the wireless transmission medium more aggressively, thereby causing | the wireless transmission medium more aggressively, thereby causing | |||
more frequent collisions and collision-induced losses. This is a | more frequent collisions and collision-induced losses. This is a | |||
topic worthy of further investigation. | topic worthy of further investigation. | |||
4.3.2. Effect of heterogeneous link rates | 3.3.2. Effect of heterogeneous link rates | |||
As discussed in [Heusse2003], the presence of clients operating over | As discussed in [Heusse2003], the presence of clients operating over | |||
slow PHY-layer link rates (e.g., a legacy 802.11b device) connected | slow PHY-layer link rates (e.g., a legacy 802.11b device) connected | |||
to a modern network may adversely impact the overall performance of | to a modern network may adversely impact the overall performance of | |||
the network. Additional test cases can be devised to evaluate the | the network. Additional test cases can be devised to evaluate the | |||
effect of clients with heterogeneous link rates on the performance of | effect of clients with heterogeneous link rates on the performance of | |||
the candidate congestion control algorithm. Such test cases, for | the candidate congestion control algorithm. Such test cases, for | |||
instance, can specify that the PHY-layer link rates for all clients | instance, can specify that the PHY-layer link rates for all clients | |||
span over a wide range (e.g., 2Mbps to 54Mbps) for investigating its | span over a wide range (e.g., 2Mbps to 54Mbps) for investigating its | |||
effect on the congestion control behavior of the real-time | effect on the congestion control behavior of the real-time | |||
interactive applications. | interactive applications. | |||
5. IANA Considerations | 4. IANA Considerations | |||
This memo includes no request to IANA. | This memo includes no request to IANA. | |||
6. Security Considerations | 5. Security Considerations | |||
The security considerations in [I-D.ietf-rmcat-eval-criteria] and the | The security considerations in [I-D.ietf-rmcat-eval-criteria] and the | |||
relevant congestion control algorithms apply. The principles for | relevant congestion control algorithms apply. The principles for | |||
congestion control are described in [RFC2914], and in particular, any | congestion control are described in [RFC2914], and in particular, any | |||
new method MUST implement safeguards to avoid congestion collapse of | new method must implement safeguards to avoid congestion collapse of | |||
the Internet. | the Internet. | |||
The evaluations of the test cases are intended to carry out in a | Given the difficulty of deterministic wireless testing, it is | |||
controlled lab environment. Hence, the applications, simulators and | recommended and expected that the tests described in this document | |||
network nodes ought to be well-behaved and should not impact the | would be done via simulations. However, in the case where these test | |||
desired results. It is important to take appropriate caution to | cases are carried out in a testbed setting, the evaluation should | |||
avoid leaking non-responsive traffic with unproven congestion | take place in a controlled lab environment. In the testbed, the | |||
avoidance behavior onto the open Internet. | applications, simulators and network nodes ought to be well-behaved | |||
and should not impact the desired results. It is important to take | ||||
appropriate caution to avoid leaking non-responsive traffic with | ||||
unproven congestion avoidance behavior onto the open Internet. | ||||
7. Acknowledgments | 6. Acknowledgments | |||
The authors would like to thank Ingemar Johansson for contributing to | ||||
the cellular test cases during the earlier stage of this draft. | ||||
The authors would like to thank Tomas Frankkila, Magnus Westerlund, | The authors would like to thank Tomas Frankkila, Magnus Westerlund, | |||
Kristofer Sandlund, Sergio Mena de la Cruz, and Mirja Kuehlewind for | Kristofer Sandlund, Sergio Mena de la Cruz, and Mirja Kuehlewind for | |||
their valuable inputs and review comments regarding this draft. | their valuable inputs and review comments regarding this draft. | |||
8. References | 7. References | |||
8.1. Normative References | 7.1. Normative References | |||
[HO-deploy-3GPP] | [HO-deploy-3GPP] | |||
TS 25.814, 3GPP., "Physical layer aspects for evolved | TS 25.814, 3GPP., "Physical layer aspects for evolved | |||
Universal Terrestrial Radio Access (UTRA)", October 2006, | Universal Terrestrial Radio Access (UTRA)", October 2006, | |||
<http://www.3gpp.org/ftp/specs/ | <http://www.3gpp.org/ftp/specs/ | |||
archive/25_series/25.814/25814-710.zip>. | archive/25_series/25.814/25814-710.zip>. | |||
[I-D.ietf-rmcat-eval-criteria] | [I-D.ietf-rmcat-eval-criteria] | |||
Singh, V., Ott, J., and S. Holmer, "Evaluating Congestion | Singh, V., Ott, J., and S. Holmer, "Evaluating Congestion | |||
Control for Interactive Real-time Media", draft-ietf- | Control for Interactive Real-time Media", draft-ietf- | |||
skipping to change at page 21, line 16 ¶ | skipping to change at page 21, line 21 ¶ | |||
IEEE, "Standard for Information technology-- | IEEE, "Standard for Information technology-- | |||
Telecommunications and information exchange between | Telecommunications and information exchange between | |||
systems Local and metropolitan area networks--Specific | systems Local and metropolitan area networks--Specific | |||
requirements Part 11: Wireless LAN Medium Access Control | requirements Part 11: Wireless LAN Medium Access Control | |||
(MAC) and Physical Layer (PHY) Specifications", 2012. | (MAC) and Physical Layer (PHY) Specifications", 2012. | |||
[NS3WiFi] "Wi-Fi Channel Model in ns-3 Simulator", | [NS3WiFi] "Wi-Fi Channel Model in ns-3 Simulator", | |||
<https://www.nsnam.org/doxygen/ | <https://www.nsnam.org/doxygen/ | |||
classns3_1_1_yans_wifi_channel.html>. | classns3_1_1_yans_wifi_channel.html>. | |||
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate | ||||
Requirement Levels", BCP 14, RFC 2119, | ||||
DOI 10.17487/RFC2119, March 1997, | ||||
<https://www.rfc-editor.org/info/rfc2119>. | ||||
[RFC5681] Allman, M., Paxson, V., and E. Blanton, "TCP Congestion | [RFC5681] Allman, M., Paxson, V., and E. Blanton, "TCP Congestion | |||
Control", RFC 5681, DOI 10.17487/RFC5681, September 2009, | Control", RFC 5681, DOI 10.17487/RFC5681, September 2009, | |||
<https://www.rfc-editor.org/info/rfc5681>. | <https://www.rfc-editor.org/info/rfc5681>. | |||
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC | [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC | |||
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, | 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, | |||
May 2017, <https://www.rfc-editor.org/info/rfc8174>. | May 2017, <https://www.rfc-editor.org/info/rfc8174>. | |||
8.2. Informative References | 7.2. Informative References | |||
[Heusse2003] | [Heusse2003] | |||
Heusse, M., Rousseau, F., Berger-Sabbatel, G., and A. | Heusse, M., Rousseau, F., Berger-Sabbatel, G., and A. | |||
Duda, "Performance anomaly of 802.11b", in Proc. 23th | Duda, "Performance anomaly of 802.11b", in Proc. 23th | |||
Annual Joint Conference of the IEEE Computer and | Annual Joint Conference of the IEEE Computer and | |||
Communications Societies, (INFOCOM'03), March 2003. | Communications Societies, (INFOCOM'03), March 2003. | |||
[HO-def-3GPP] | [HO-def-3GPP] | |||
TR 21.905, 3GPP., "Vocabulary for 3GPP Specifications", | TR 21.905, 3GPP., "Vocabulary for 3GPP Specifications", | |||
December 2009, <http://www.3gpp.org/ftp/specs/ | December 2009, <http://www.3gpp.org/ftp/specs/ | |||
skipping to change at page 22, line 5 ¶ | skipping to change at page 22, line 5 ¶ | |||
Protocol specification", December 2011, | Protocol specification", December 2011, | |||
<http://www.3gpp.org/ftp/specs/ | <http://www.3gpp.org/ftp/specs/ | |||
archive/36_series/36.331/36331-990.zip>. | archive/36_series/36.331/36331-990.zip>. | |||
[HO-UMTS-3GPP] | [HO-UMTS-3GPP] | |||
TS 25.331, 3GPP., "Radio Resource Control (RRC); Protocol | TS 25.331, 3GPP., "Radio Resource Control (RRC); Protocol | |||
specification", December 2011, | specification", December 2011, | |||
<http://www.3gpp.org/ftp/specs/ | <http://www.3gpp.org/ftp/specs/ | |||
archive/25_series/25.331/25331-990.zip>. | archive/25_series/25.331/25331-990.zip>. | |||
[I-D.ietf-rmcat-cc-requirements] | ||||
Jesup, R. and Z. Sarker, "Congestion Control Requirements | ||||
for Interactive Real-Time Media", draft-ietf-rmcat-cc- | ||||
requirements-09 (work in progress), December 2014. | ||||
[NS-2] "ns-2", December 2014, | [NS-2] "ns-2", December 2014, | |||
<http://nsnam.sourceforge.net/wiki/index.php/Main_Page>. | <http://nsnam.sourceforge.net/wiki/index.php/Main_Page>. | |||
[NS-3] "ns-3 Network Simulator", <https://www.nsnam.org/>. | [NS-3] "ns-3 Network Simulator", <https://www.nsnam.org/>. | |||
[QoS-3GPP] | [QoS-3GPP] | |||
TS 23.203, 3GPP., "Policy and charging control | TS 23.203, 3GPP., "Policy and charging control | |||
architecture", June 2011, <http://www.3gpp.org/ftp/specs/ | architecture", June 2011, <http://www.3gpp.org/ftp/specs/ | |||
archive/23_series/23.203/23203-990.zip>. | archive/23_series/23.203/23203-990.zip>. | |||
skipping to change at page 22, line 35 ¶ | skipping to change at page 22, line 30 ¶ | |||
Zaheduzzaman Sarker | Zaheduzzaman Sarker | |||
Ericsson AB | Ericsson AB | |||
Laboratoriegraend 11 | Laboratoriegraend 11 | |||
Luleae 97753 | Luleae 97753 | |||
Sweden | Sweden | |||
Phone: +46 107173743 | Phone: +46 107173743 | |||
Email: zaheduzzaman.sarker@ericsson.com | Email: zaheduzzaman.sarker@ericsson.com | |||
Ingemar Johansson | ||||
Ericsson AB | ||||
Laboratoriegraend 11 | ||||
Luleae 97753 | ||||
Sweden | ||||
Phone: +46 10 7143042 | ||||
Email: ingemar.s.johansson@ericsson.com | ||||
Xiaoqing Zhu | Xiaoqing Zhu | |||
Cisco Systems | Cisco Systems | |||
12515 Research Blvd., Building 4 | 12515 Research Blvd., Building 4 | |||
Austin, TX 78759 | Austin, TX 78759 | |||
USA | USA | |||
Email: xiaoqzhu@cisco.com | Email: xiaoqzhu@cisco.com | |||
Jiantao Fu | Jiantao Fu | |||
Cisco Systems | Cisco Systems | |||
771 Alder Drive | 771 Alder Drive | |||
Milpitas, CA 95035 | Milpitas, CA 95035 | |||
USA | USA | |||
Email: jianfu@cisco.com | Email: jianfu@cisco.com | |||
Wei-Tian Tan | Wei-Tian Tan | |||
Cisco Systems | Cisco Systems | |||
510 McCarthy Blvd | 510 McCarthy Blvd | |||
Milpitas, CA 95035 | Milpitas, CA 95035 | |||
USA | USA | |||
Email: dtan2@cisco.com | Email: dtan2@cisco.com | |||
Michael A. Ramalho | Michael A. Ramalho | |||
AcousticComms Consulting | AcousticComms Consulting | |||
End of changes. 63 change blocks. | ||||
141 lines changed or deleted | 125 lines changed or added | |||
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