wdiff rfc8172v1.txt rfc8172.txt

Internet Engineering Task Force (IETF) A. Morton
Request for Comments: 8172 AT&T Labs
Category: Informational May July 2017
ISSN: 2070-1721

Considerations for Benchmarking Virtual Network Functions and Their
Infrastructure

Abstract

The Benchmarking Methodology Working Group has traditionally
conducted laboratory characterization of dedicated physical
implementations of internetworking functions. This memo investigates
additional considerations when network functions are virtualized and
performed in general-purpose hardware.

Status of This Memo

This document is not an Internet Standards Track specification; it is
published for informational purposes.

This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 7841.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc8172.

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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Considerations for Hardware and Testing . . . . . . . . . . . 4
3.1. Hardware Components . . . . . . . . . . . . . . . . . . . 4
3.2. Configuration Parameters . . . . . . . . . . . . . . . . 5
3.3. Testing Strategies . . . . . . . . . . . . . . . . . . . 6
3.4. Attention to Shared Resources . . . . . . . . . . . . . . 7
4. Benchmarking Considerations . . . . . . . . . . . . . . . . . 7 8
4.1. Comparison with Physical Network Functions . . . . . . . 8
4.2. Continued Emphasis on Black-Box Benchmarks . . . . . . . 8
4.3. New Benchmarks and Related Metrics . . . . . . . . . . . 9
4.4. Assessment of Benchmark Coverage . . . . . . . . . . . . 9 10
4.5. Power Consumption . . . . . . . . . . . . . . . . . . . . 12
5. Security Considerations . . . . . . . . . . . . . . . . . . . 12
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 13
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
7.1. Normative References . . . . . . . . . . . . . . . . . . 13
7.2. Informative References . . . . . . . . . . . . . . . . . 13
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 14 15
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 15

1. Introduction

The Benchmarking Methodology Working Group (BMWG) has traditionally
conducted laboratory characterization of dedicated physical
implementations of internetworking functions (or physical network
functions (PNFs)). The black-box benchmarks of throughput, latency,
forwarding rates, and others have served our industry for many years.
[RFC1242] and [RFC2544] are the cornerstones of the work.

An emerging

A set of service provider and vendor development goals is
to has emerged:
reduce costs while increasing flexibility of network devices, devices and
drastically accelerate their deployment. reduce deployment time. Network Function Virtualization
(NFV) has the promise to achieve these goals and therefore has
garnered much attention. It now seems certain that some network
functions will be virtualized following the success of cloud
computing and virtual desktops supported by sufficient network path
capacity, performance, and widespread deployment; many of the same
techniques will help achieve NFV.

In the context of Virtual Network Functions (VNFs), the supporting
Infrastructure requires general-purpose computing systems, storage
systems, networking systems, virtualization support systems (such as
hypervisors), and management systems for the virtual and physical
resources. There will be many potential suppliers of Infrastructure
systems and significant flexibility in configuring the systems for
best performance. There are also many potential suppliers of VNFs,
adding to the combinations possible in this environment. The
separation of hardware and software suppliers has a profound
implication on benchmarking activities: much more of the internal
configuration of the black-box Device Under Test (DUT) must now be
specified and reported with the results, to foster both repeatability
and comparison testing at a later time.

Consider the following user story as further background and
motivation:

I'm designing and building my NFV Infrastructure platform. The
first steps were easy because I had a small number of categories
of VNFs to support and the VNF vendor gave hardware
recommendations that I followed. Now I need to deploy more VNFs
from new vendors, and there are different hardware
recommendations. How well will the new VNFs perform on my
existing hardware? Which among several new VNFs in a given
category are most efficient in terms of capacity they deliver?
And, when I operate multiple categories of VNFs (and PNFs)
*concurrently* on a hardware platform such that they share
resources, what are the new performance limits, and what are the
software design choices I can make to optimize my chosen hardware
platform? Conversely, what hardware platform upgrades should I
pursue to increase the capacity of these concurrently operating
VNFs?

See <http://www.etsi.org/technologies-clusters/technologies/nfv> for
more background; the white papers there may be a useful starting
place. The "NFV Performance & Portability Best Practices" document
[NFV.PER001] is particularly relevant to BMWG. There are also
documents available in among the Open Area
<http://docbox.etsi.org/ISG/NFV/Open/Latest_Drafts/>, Approved ETSI NFV Specifications
[Approved_ETSI_NFV], including
drafts documents describing Infrastructure
performance aspects and service quality. quality metrics, and drafts in the
ETSI NFV Open Area [Draft_ETSI_NFV], which may also have relevance to
benchmarking.

1.1. Requirements Language

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.

2. Scope

At the time of this writing, BMWG is considering the new topic of
Virtual Network Functions and related Infrastructure to ensure that
common issues are recognized from the start, using start; background materials
from industry and respective standards development organizations,
e.g., IETF or organizations and Open Source
development projects (e.g., IETF, ETSI NFV. NFV, and the Open Platform for
Network Function Virtualization (OPNFV)) are being used.

This memo investigates additional methodological considerations
necessary when benchmarking VNFs instantiated and hosted in general-
purpose hardware, using bare metal hypervisors [BareMetal] or other
isolation environments such as Linux containers. An essential
consideration is benchmarking physical and virtual network functions Virtual Network Functions
in the same way when possible, thereby allowing direct comparison.
Benchmarking combinations of physical and virtual devices and
functions in a System Under Test (SUT) is another topic of keen
interest.

A clearly related goal: the goal is investigating benchmarks for the capacity
of a general-
purpose general-purpose platform to host a plurality of VNF instances should be
investigated. instances.
Existing networking technology benchmarks will also be considered for
adaptation to NFV and closely associated technologies.

A non-goal is any overlap with traditional computer benchmark
development and their specific metrics (SPECmark (e.g., SPECmark suites such as
SPECCPU).
SPEC CPU).

A continued non-goal is any form of architecture development related
to NFV and associated technologies in BMWG, consistent with all
chartered work since BMWG began in 1989.

3. Considerations for Hardware and Testing

This section lists the new considerations that must be addressed to
benchmark VNF(s) and their supporting infrastructure. Infrastructure. The SUT is
composed of the hardware platform components, the VNFs installed, and
many other supporting systems. It is critical to document all
aspects of the SUT to foster repeatability.

3.1. Hardware Components

New

The following new hardware components will become part of the test setup.
setup:

1. High-volume server platforms (general-purpose, possibly with
virtual technology enhancements)
2. Storage systems with large capacity, high speed, and high
reliability

3. Network interface ports specially designed for efficient service
of many virtual Network Interface Cards (NICs)

4. High-capacity Ethernet switches

The components above are subjects for development of specialized
benchmarks that focus on the special demands of network function
deployment.

Labs conducting comparisons of different VNFs may be able to use the
same hardware platform over many studies, until the steady march of
innovations overtakes their capabilities (as happens with the lab's
traffic generation and testing devices today).

3.2. Configuration Parameters

It will be necessary to configure and document the settings for the
entire general-purpose platform to ensure repeatability and foster
future comparisons, including, but clearly not limited to, the
following:

o number of server blades (shelf occupation)

o CPUs

o caches

o memory

o storage system

o I/O

as well as configurations that support the devices that host the VNF
itself:

o Hypervisor (or other forms of virtual function hosting)

o Virtual Machine (VM)

o Infrastructure virtual network (which interconnects virtual
machines with physical network interfaces or with each other
through virtual switches, for example)

and finally, the VNF itself, with items such as:

o specific function being implemented in VNF

o reserved resources for each function (e.g., CPU pinning and Non-
Uniform Memory Access (NUMA) node assignment)

o number of VNFs (or sub-VNF components, each with its own VM) in
the service function chain (see Section 1.1 of [RFC7498] for a
definition of service function chain)

o number of physical interfaces and links transited in the service
function chain

In the physical device benchmarking context, most of the
corresponding infrastructure Infrastructure configuration choices were determined by
the vendor. Although the platform itself is now one of the
configuration variables, it is important to maintain emphasis on the
networking benchmarks and capture the platform variables as input
factors.

3.3. Testing Strategies

The concept of characterizing performance at capacity limits may
change. For example:

1. It may be more representative of system capacity to characterize
the case where virtual machines (VM, the VMs hosting the VNFs) VNFs are operating at 50%
utilization and therefore sharing the "real" processing power
across many VMs.

2. Another important test case stems from the need for partitioning to partition (or
isolate) network functions. A noisy neighbor (VM hosting a VNF
in an infinite loop) would ideally be isolated, and isolated; the performance
of other VMs would continue according to their specifications. specifications,
and tests would evaluate the degree of isolation.

3. System errors will likely occur as transients, implying a
distribution of performance characteristics with a long tail
(like latency) and leading to the need for longer-term tests of
each set of configuration and test parameters.

4. The desire for elasticity and flexibility among network functions
will include tests where there is constant flux in the number of
VM instances, the resources the VMs require, and the setup/
teardown of network paths that support VM connectivity. Requests
for and instantiation of new VMs, along with releases for VMs
hosting VNFs that are no longer needed, would be a normal
operational condition. In other words, benchmarking should
include scenarios with production life-cycle management of VMs
and their VNFs and network connectivity in progress, including
VNF scaling up/down operations, as well as static configurations.

5. All physical things can fail, and benchmarking efforts can also
examine recovery aided by the virtual architecture with different
approaches to resiliency.

6. The sheer number of test conditions and configuration
combinations encourage increased efficiency, including automated
testing arrangements, combination sub-sampling through an
understanding of inter-relationships, and machine-readable test
results.

3.4. Attention to Shared Resources

Since many components of the new NFV Infrastructure are virtual, test
setup design must have prior knowledge of interactions/dependencies
within the various resource domains in the SUT. For example, a
virtual machine performing the role of a traditional tester function,
such as generating and/or receiving traffic, should avoid sharing any
SUT resources with the DUT. Otherwise, the results will have
unexpected dependencies not encountered in physical device
benchmarking.

Note that the term "tester" has traditionally referred to devices
dedicated to testing in BMWG literature. In this new context,
"tester" additionally refers to functions dedicated to testing, which
may be either virtual or physical. "Tester" has never referred to
the individuals performing the tests.

The shared-resource aspect of possibility to use shared resources in test design while
producing useful results remains one of the critical challenges to overcome in a way to produce useful results.
overcome. Benchmarking setups may designate isolated resources for
the DUT and other critical support components (such as the host/kernel) host/
kernel) as the first baseline step and add other loading processes.
The added complexity of each setup leads to shared-resource testing
scenarios, where the characteristics of the competing load (in terms
of memory, storage, and CPU utilization) will directly affect the
benchmarking results (and variability of the results), but the
results should reconcile with the baseline.

The physical test device remains a solid foundation to compare with
results using combinations of physical and virtual test functions or
results using only virtual testers when necessary to assess virtual
interfaces and other virtual functions.

4. Benchmarking Considerations

This section discusses considerations related to benchmarks
applicable to VNFs and their associated technologies.

4.1. Comparison with Physical Network Functions

In order to compare the performance of VNFs and system
implementations with their physical counterparts, identical
benchmarks must be used. Since BMWG has already developed
specifications for many network functions, there will be re-use of
existing benchmarks through references, while allowing for the
possibility of benchmark curation during development of new
methodologies. Consideration should be given to quantifying the
number of parallel VNFs required to achieve comparable scale/capacity
with a given physical device or whether some limit of scale was
reached before the VNFs could achieve the comparable level. Again,
implementation based on different hypervisors or other virtual
function hosting remain as critical factors in performance
assessment.

4.2. Continued Emphasis on Black-Box Benchmarks

When the network functions under test are based on open-source code,
there may be a tendency to rely on internal measurements to some
extent, especially when the externally observable phenomena only
support an inference of internal events (such as routing protocol
convergence observed in the data plane). Examples include CPU/Core
utilization, network utilization, storage utilization, and memory
committed/used. These "white-box" metrics provide one view of the
resource footprint of a VNF. Note that the resource utilization
metrics do not easily match the 3x4 Matrix, described in Section 4.4.

However, external observations remain essential as the basis for
benchmarks. Internal observations with fixed specification and
interpretation may be provided in parallel (as auxiliary metrics), to
assist the development of operations procedures when the technology
is deployed, for example. Internal metrics and measurements from
open-source implementations may be the only direct source of
performance results in a desired dimension, but corroborating
external observations are still required to assure the integrity of
measurement discipline was maintained for all reported results.

A related aspect of benchmark development is where the scope includes
multiple approaches to a common function under the same benchmark.
For example, there are many ways to arrange for activation of a
network path between interface points, and the activation times can
be compared if the start-to-stop activation interval has a generic
and unambiguous definition. Thus, generic benchmark definitions are
preferred over technology/protocol-specific definitions where
possible.

4.3. New Benchmarks and Related Metrics

There will be new classes of benchmarks needed for network design and
assistance when developing operational practices (possibly automated
management and orchestration of deployment scale). Examples follow
in the paragraphs below, many of which are prompted by the goals of
increased elasticity and flexibility of the network functions, along
with accelerated reduced deployment times.

o Time to deploy VNFs: In cases where the general-purpose hardware
is already deployed and ready for service, it is valuable to know
the response time when a management system is tasked with
"standing up" 100s of virtual machines and the VNFs they will
host.

o Time to migrate VNFs: In cases where a rack or shelf of hardware
must be removed from active service, it is valuable to know the
response time when a management system is tasked with "migrating"
some number of virtual machines and the VNFs they currently host
to alternate hardware that will remain in service.

o Time to create a virtual network in the general-purpose
infrastructure:
Infrastructure: This is a somewhat simplified version of existing
benchmarks for convergence time, in that the process is initiated
by a request from (centralized or distributed) control, rather
than inferred from network events (link failure). The successful
response time would remain dependent on data-plane observations to
confirm that the network is ready to perform.

o Effect of verification measurements on performance: A complete
VNF, or something as simple as a new policy to implement in a VNF,
is implemented. The action to verify instantiation of the VNF or
policy could affect performance during normal operation.

Also, it appears to be valuable to measure traditional packet
transfer performance metrics during the assessment of traditional and
new benchmarks, including metrics that may be used to support service
engineering such as the spatial composition metrics found in
[RFC6049]. Examples include mean one-way delay in Section 4.1 of
[RFC6049], Packet Delay Variation (PDV) in [RFC5481], and Packet
Reordering [RFC4737] [RFC4689].

4.4. Assessment of Benchmark Coverage

It can be useful to organize benchmarks according to their applicable
life-cycle stage and the performance criteria they were designed to
assess. The table below (derived from [X3.102]) provides a way to
organize benchmarks such that there is a clear indication of coverage
for the intersection of life-cycle stages and performance criteria.

|----------------------------------------------------------|
| | | | |
| | SPEED | ACCURACY | RELIABILITY |
| | | | |
|----------------------------------------------------------|
| | | | |
| Activation | | | |
| | | | |
|----------------------------------------------------------|
| | | | |
| Operation | | | |
| | | | |
|----------------------------------------------------------|
| | | | |
| De-activation | | | |
| | | | |
|----------------------------------------------------------|

For example, the "Time to deploy VNFs" benchmark described above
would be placed in the intersection of Activation and Speed, making
it clear that there are other potential performance criteria to
benchmark, such as the "percentage of unsuccessful VM/VNF stand-ups"
in a set of 100 attempts. This example emphasizes that the
Activation and De-activation life-cycle stages are key areas for NFV
and related infrastructure Infrastructure and encourages expansion beyond
traditional benchmarks for normal operation. Thus, reviewing the
benchmark coverage using this table (sometimes called the 3x3 matrix) Matrix)
can be a worthwhile exercise in BMWG.

In one of the first applications of the 3x3 matrix Matrix in BMWG
[SDN-BENCHMARK], we discovered that metrics on measured size,
capacity, or scale do not easily match one of the three columns
above. Following discussion, this was resolved in two ways:

o Add a column, Scale, for use when categorizing and assessing the
coverage of benchmarks (without measured results). Examples An example of
this use are is found in [SDN-BENCHMARK] and [OPNFV-BENCHMARK]. [OPNFV-BENCHMARK] (and a variation may be
found in [SDN-BENCHMARK]). This is the 3x4 Matrix.

o If using the matrix to report results in an organized way, keep
size, capacity, and scale metrics separate from the 3x3 matrix Matrix and
incorporate them in the report with other qualifications of the
results.

Note that the resource utilization (e.g., CPU) metrics do not fit in
the Matrix. matrix. They are not benchmarks, and omitting them confirms
their status as auxiliary metrics. Resource assignments are
configuration parameters, and these are reported separately.

This approach encourages use of the 3x3 matrix Matrix to organize reports of
results, where the capacity at which the various metrics were
measured could be included in the title of the matrix (and results
for multiple capacities would result in separate 3x3 matrices, Matrices, if
there were sufficient measurements/results to organize in that way).

For example, results for each VM and VNF could appear in the 3x3
matrix,
Matrix, organized to illustrate resource occupation (CPU Cores) in a
particular physical computing system, as shown below.

VNF#1
.-----------.
|__|__|__|__|
Core 1 |__|__|__|__|
|__|__|__|__|
| | | | |
'-----------'
VNF#2
.-----------.
|__|__|__|__|
Cores 2-5 |__|__|__|__|
|__|__|__|__|
| | | | |
'-----------'
VNF#3 VNF#4 VNF#5
.-----------. .-----------. .-----------.
|__|__|__|__| |__|__|__|__| |__|__|__|__|
Core 6 |__|__|__|__| |__|__|__|__| |__|__|__|__|
|__|__|__|__| |__|__|__|__| |__|__|__|__|
| | | | | | | | | | | | | | |
'-----------' '-----------' '-----------'
VNF#6
.-----------.
|__|__|__|__|
Core 7 |__|__|__|__|
|__|__|__|__|
| | | | |
'-----------'
The combination of tables above could be built incrementally,
beginning with VNF#1 and one Core, then adding VNFs according to
their supporting core Core assignments. X-Y plots of critical benchmarks
would also provide insight to the effect of increased hardware
utilization. All VNFs might be of the same type, or to match a
production environment, there could be VNFs of multiple types and
categories. In this figure, VNFs #3-#5 are assumed to require small
CPU resources, while VNF#2 requires four cores Cores to perform its
function.

4.5. Power Consumption

Although there is incomplete work to benchmark physical network
function power consumption in a meaningful way, the desire to measure
the physical infrastructure Infrastructure supporting the virtual functions only
adds to the need. Both maximum power consumption and dynamic power
consumption (with varying load) would be useful. The Intelligent
Platform Management Interface (IPMI) standard [IPMI2.0] has been
implemented by many manufacturers and supports measurement of
instantaneous energy consumption.

To assess the instantaneous energy consumption of virtual resources,
it may be possible to estimate the value using an overall metric
based on utilization readings, according to [NFVIaas-FRAMEWORK].

5. Security Considerations

Benchmarking activities as described in this memo are limited to
technology characterization of a DUT/SUT using controlled stimuli in
a laboratory environment, with dedicated address space and the
constraints specified in the sections above.

The benchmarking network topology will be an independent test setup
and MUST NOT be connected to devices that may forward the test
traffic into a production network or misroute traffic to the test
management network.

Further, benchmarking is performed on a "black-box" basis, relying
solely on measurements observable external to the DUT/SUT.

Special capabilities SHOULD NOT exist in the DUT/SUT specifically for
benchmarking purposes. Any implications for network security arising
from the DUT/SUT SHOULD be identical in the lab and in production
networks.

6. IANA Considerations

This document does not require any IANA actions.

7. References

7.1. Normative References

[NFV.PER001]
ETSI, "Network Functions Virtualisation (NFV); NFV Function Virtualization: Performance &
Portability Best Practices", ETSI GS NFV-PER 001, V1.1.1, June V1.1.2,
December 2014.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.

[RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for
Network Interconnect Devices", RFC 2544,
DOI 10.17487/RFC2544, March 1999,
<http://www.rfc-editor.org/info/rfc2544>.

[RFC4689] Poretsky, S., Perser, J., Erramilli, S., and S. Khurana,
"Terminology for Benchmarking Network-layer Traffic
Control Mechanisms", RFC 4689, DOI 10.17487/RFC4689,
October 2006, <http://www.rfc-editor.org/info/rfc4689>.

[RFC4737] Morton, A., Ciavattone, L., Ramachandran, G., Shalunov,
S., and J. Perser, "Packet Reordering Metrics", RFC 4737,
DOI 10.17487/RFC4737, November 2006,
<http://www.rfc-editor.org/info/rfc4737>.

[RFC7498] Quinn, P., Ed. and T. Nadeau, Ed., "Problem Statement for
Service Function Chaining", RFC 7498,
DOI 10.17487/RFC7498, April 2015,
<http://www.rfc-editor.org/info/rfc7498>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <http://www.rfc-editor.org/info/rfc8174>.

7.2. Informative References

[Approved_ETSI_NFV]
ETSI, Network Functions Virtualisation Technical
Committee, "ETSI NFV",
<http://www.etsi.org/standards-search>.

[BareMetal]
Popek, G. and R. Goldberg, "Formal requirements for
virtualizable third generation architectures",
Communications of the ACM, Volume 17, Issue 7, Pages
412-421, DOI 10.1145/361011.361073, July 1974.

[Draft_ETSI_NFV]
ETSI, "Network Functions Virtualisation: Specifications",
<http://www.etsi.org/technologies-clusters/technologies/
nfv>.

[IPMI2.0] Intel Corporation, Hewlett-Packard Company, NEC
Corporation, and Dell Inc., "Intelligent Platform
Management Interface Specification v2.0 (with latest
errata)", April 2015,
<http://www.intel.com/content/www/us/en/servers/ipmi/ipmi-
intelligent-platform-mgt-interface-spec-2nd-gen-v2-0-spec-
update.html>.
<http://www.intel.com/content/dam/www/public/us/en/
documents/specification-updates/ipmi-intelligent-platform-
mgt-interface-spec-2nd-gen-v2-0-spec-update.pdf>.

[NFVIaas-FRAMEWORK]
Krishnan, R., Figueira, N., Krishnaswamy, D., Lopez, D.,
Wright, S., Hinrichs, T., Krishnaswamy, R., and A. Yerra,
"NFVIaaS Architectural Framework for Policy Based Resource
Placement and Scheduling", Work in Progress, draft-
krishnan-nfvrg-policy-based-rm-nfviaas-06, March 2016.

[OPNFV-BENCHMARK]
Tahhan, M., O'Mahony, B., and A. Morton, "Benchmarking
Virtual Switches in OPNFV", Work in Progress, draft-ietf-
bmwg-vswitch-opnfv-03, May
bmwg-vswitch-opnfv-04, June 2017.

[RFC1242] Bradner, S., "Benchmarking Terminology for Network
Interconnection Devices", RFC 1242, DOI 10.17487/RFC1242,
July 1991, <http://www.rfc-editor.org/info/rfc1242>.

[RFC5481] Morton, A. and B. Claise, "Packet Delay Variation
Applicability Statement", RFC 5481, DOI 10.17487/RFC5481,
March 2009, <http://www.rfc-editor.org/info/rfc5481>.

[RFC6049] Morton, A. and E. Stephan, "Spatial Composition of
Metrics", RFC 6049, DOI 10.17487/RFC6049, January 2011,
<http://www.rfc-editor.org/info/rfc6049>.

[SDN-BENCHMARK]
Vengainathan, B., Basil, A., Tassinari, M., Manral, V.,
and S. Banks, "Benchmarking Methodology "Terminology for Benchmarking SDN Controller
Performance", Work in Progress, draft-ietf-bmwg-sdn-
controller-benchmark-meth-03, January
controller-benchmark-term-04, June 2017.

[X3.102] ANSI, "Information Systems - Data Communication Systems
and Services - User-Oriented Performance Parameters
Communications Framework", ANSI X3.102, 1983.

Acknowledgements

The author acknowledges an encouraging conversation on this topic
with Mukhtiar Shaikh and Ramki Krishnan in November 2013. Bhavani
Parise and Ilya Varlashkin have provided useful suggestions to expand
these considerations. Bhuvaneswaran Vengainathan has already tried
the 3x3 matrix Matrix with the SDN controller document and contributed to
many discussions. Scott Bradner quickly pointed out shared resource
dependencies in an early vSwitch measurement proposal, and the topic
was included here as a key consideration. Further development was
encouraged by Barry Constantine's comments following the BMWG session
at IETF 92: the session itself was an affirmation for this memo.
There have been many interesting contributions from Maryam Tahhan,
Marius Georgescu, Jacob Rapp, Saurabh Chattopadhyay, and others.

Author's Address

Al Morton
AT&T Labs
200 Laurel Avenue South
Middletown, NJ 07748
United States of America

Phone: +1 732 420 1571
Fax: +1 732 368 1192
Email: acmorton@att.com
URI: http://home.comcast.net/~acmacm/