draft-ietf-ippm-spatial-composition-07.txt   draft-ietf-ippm-spatial-composition-08.txt 
Network Working Group A. Morton Network Working Group A. Morton
Internet-Draft AT&T Labs Internet-Draft AT&T Labs
Intended status: Standards Track E. Stephan Intended status: Standards Track E. Stephan
Expires: January 14, 2009 France Telecom Division R&D Expires: September 8, 2009 France Telecom Division R&D
July 13, 2008 March 7, 2009
Spatial Composition of Metrics Spatial Composition of Metrics
draft-ietf-ippm-spatial-composition-07 draft-ietf-ippm-spatial-composition-08
Status of this Memo Status of this Memo
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Abstract Abstract
This memo utilizes IPPM metrics that are applicable to both complete This memo utilizes IPPM metrics that are applicable to both complete
paths and sub-paths, and defines relationships to compose a complete paths and sub-paths, and defines relationships to compose a complete
path metric from the sub-path metrics with some accuracy w.r.t. the path metric from the sub-path metrics with some accuracy w.r.t. the
actual metrics. This is called Spatial Composition in RFC 2330. The actual metrics. This is called Spatial Composition in RFC 2330. The
memo refers to the Framework for Metric Composition, and provides memo refers to the Framework for Metric Composition, and provides
background and motivation for combining metrics to derive others. background and motivation for combining metrics to derive others.
The descriptions of several composed metrics and statistics follow. The descriptions of several composed metrics and statistics follow.
skipping to change at page 2, line 12 skipping to change at page 3, line 7
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
In this memo, the characters "<=" should be read as "less than or In this memo, the characters "<=" should be read as "less than or
equal to" and ">=" as "greater than or equal to". equal to" and ">=" as "greater than or equal to".
Table of Contents Table of Contents
1. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Scope and Application . . . . . . . . . . . . . . . . . . . . 5 3. Scope and Application . . . . . . . . . . . . . . . . . . . . 6
3.1. Scope of work . . . . . . . . . . . . . . . . . . . . . . 6 3.1. Scope of work . . . . . . . . . . . . . . . . . . . . . . 7
3.2. Application . . . . . . . . . . . . . . . . . . . . . . . 6 3.2. Application . . . . . . . . . . . . . . . . . . . . . . . 7
3.3. Incomplete Information . . . . . . . . . . . . . . . . . . 6 3.3. Incomplete Information . . . . . . . . . . . . . . . . . . 7
4. Common Specifications for Composed Metrics . . . . . . . . . . 7 4. Common Specifications for Composed Metrics . . . . . . . . . . 8
4.1. Name: Type-P . . . . . . . . . . . . . . . . . . . . . . . 7 4.1. Name: Type-P . . . . . . . . . . . . . . . . . . . . . . . 8
4.1.1. Metric Parameters . . . . . . . . . . . . . . . . . . 7 4.1.1. Metric Parameters . . . . . . . . . . . . . . . . . . 8
4.1.2. Definition and Metric Units . . . . . . . . . . . . . 8 4.1.2. Definition and Metric Units . . . . . . . . . . . . . 9
4.1.3. Discussion and other details . . . . . . . . . . . . . 8 4.1.3. Discussion and other details . . . . . . . . . . . . . 9
4.1.4. Statistic: . . . . . . . . . . . . . . . . . . . . . . 8 4.1.4. Statistic: . . . . . . . . . . . . . . . . . . . . . . 9
4.1.5. Composition Function . . . . . . . . . . . . . . . . . 8 4.1.5. Composition Function . . . . . . . . . . . . . . . . . 9
4.1.6. Statement of Conjecture and Assumptions . . . . . . . 8 4.1.6. Statement of Conjecture and Assumptions . . . . . . . 9
4.1.7. Justification of the Composition Function . . . . . . 8 4.1.7. Justification of the Composition Function . . . . . . 9
4.1.8. Sources of Deviation from the Ground Truth . . . . . . 9 4.1.8. Sources of Deviation from the Ground Truth . . . . . . 10
4.1.9. Specific cases where the conjecture might fail . . . . 10 4.1.9. Specific cases where the conjecture might fail . . . . 11
4.1.10. Application of Measurement Methodology . . . . . . . . 10 4.1.10. Application of Measurement Methodology . . . . . . . . 11
5. One-way Delay Composed Metrics and Statistics . . . . . . . . 10 5. One-way Delay Composed Metrics and Statistics . . . . . . . . 11
5.1. Name: 5.1. Name:
Type-P-Finite-One-way-Delay-Poisson/Periodic-Stream . . . 10 Type-P-Finite-One-way-Delay-Poisson/Periodic-Stream . . . 11
5.1.1. Metric Parameters . . . . . . . . . . . . . . . . . . 10 5.1.1. Metric Parameters . . . . . . . . . . . . . . . . . . 11
5.1.2. Definition and Metric Units . . . . . . . . . . . . . 11 5.1.2. Definition and Metric Units . . . . . . . . . . . . . 12
5.1.3. Discussion and other details . . . . . . . . . . . . . 11 5.1.3. Discussion and other details . . . . . . . . . . . . . 12
5.2. Name: Type-P-Finite-Composite-One-way-Delay-Mean . . . . . 11 5.2. Name: Type-P-Finite-Composite-One-way-Delay-Mean . . . . . 12
5.2.1. Metric Parameters . . . . . . . . . . . . . . . . . . 11 5.2.1. Metric Parameters . . . . . . . . . . . . . . . . . . 12
5.2.2. Definition and Metric Units of the Mean Statistic . . 11 5.2.2. Definition and Metric Units of the Mean Statistic . . 12
5.2.3. Discussion and other details . . . . . . . . . . . . . 12 5.2.3. Discussion and other details . . . . . . . . . . . . . 13
5.2.4. Composition Function: Sum of Means . . . . . . . . . . 12 5.2.4. Composition Function: Sum of Means . . . . . . . . . . 13
5.2.5. Statement of Conjecture and Assumptions . . . . . . . 12 5.2.5. Statement of Conjecture and Assumptions . . . . . . . 13
5.2.6. Justification of the Composition Function . . . . . . 13 5.2.6. Justification of the Composition Function . . . . . . 14
5.2.7. Sources of Deviation from the Ground Truth . . . . . . 13 5.2.7. Sources of Deviation from the Ground Truth . . . . . . 14
5.2.8. Specific cases where the conjecture might fail . . . . 13 5.2.8. Specific cases where the conjecture might fail . . . . 14
5.2.9. Application of Measurement Methodology . . . . . . . . 13 5.2.9. Application of Measurement Methodology . . . . . . . . 14
5.3. Name: Type-P-Finite-Composite-One-way-Delay-Minimum . . . 13 5.3. Name: Type-P-Finite-Composite-One-way-Delay-Minimum . . . 14
5.3.1. Metric Parameters . . . . . . . . . . . . . . . . . . 13 5.3.1. Metric Parameters . . . . . . . . . . . . . . . . . . 14
5.3.2. Definition and Metric Units of the Mean Statistic . . 13 5.3.2. Definition and Metric Units of the Mean Statistic . . 14
5.3.3. Discussion and other details . . . . . . . . . . . . . 14 5.3.3. Discussion and other details . . . . . . . . . . . . . 15
5.3.4. Composition Function: Sum of Means . . . . . . . . . . 14 5.3.4. Composition Function: Sum of Means . . . . . . . . . . 15
5.3.5. Statement of Conjecture and Assumptions . . . . . . . 14 5.3.5. Statement of Conjecture and Assumptions . . . . . . . 15
5.3.6. Justification of the Composition Function . . . . . . 14 5.3.6. Justification of the Composition Function . . . . . . 15
5.3.7. Sources of Deviation from the Ground Truth . . . . . . 14 5.3.7. Sources of Deviation from the Ground Truth . . . . . . 15
5.3.8. Specific cases where the conjecture might fail . . . . 15 5.3.8. Specific cases where the conjecture might fail . . . . 16
5.3.9. Application of Measurement Methodology . . . . . . . . 15 5.3.9. Application of Measurement Methodology . . . . . . . . 16
6. Loss Metrics and Statistics . . . . . . . . . . . . . . . . . 15 6. Loss Metrics and Statistics . . . . . . . . . . . . . . . . . 16
6.1. Type-P-Composite-One-way-Packet-Loss-Empirical-Probability 15 6.1. Type-P-Composite-One-way-Packet-Loss-Empirical-Probability 16
6.1.1. Metric Parameters: . . . . . . . . . . . . . . . . . . 15 6.1.1. Metric Parameters: . . . . . . . . . . . . . . . . . . 16
6.1.2. Definition and Metric Units . . . . . . . . . . . . . 15 6.1.2. Definition and Metric Units . . . . . . . . . . . . . 16
6.1.3. Discussion and other details . . . . . . . . . . . . . 15 6.1.3. Discussion and other details . . . . . . . . . . . . . 16
6.1.4. Statistic: 6.1.4. Statistic:
Type-P-One-way-Packet-Loss-Empirical-Probability . . . 15 Type-P-One-way-Packet-Loss-Empirical-Probability . . . 16
6.1.5. Composition Function: Composition of Empirical 6.1.5. Composition Function: Composition of Empirical
Probabilities . . . . . . . . . . . . . . . . . . . . 16 Probabilities . . . . . . . . . . . . . . . . . . . . 17
6.1.6. Statement of Conjecture and Assumptions . . . . . . . 16 6.1.6. Statement of Conjecture and Assumptions . . . . . . . 17
6.1.7. Justification of the Composition Function . . . . . . 16 6.1.7. Justification of the Composition Function . . . . . . 17
6.1.8. Sources of Deviation from the Ground Truth . . . . . . 16 6.1.8. Sources of Deviation from the Ground Truth . . . . . . 17
6.1.9. Specific cases where the conjecture might fail . . . . 16 6.1.9. Specific cases where the conjecture might fail . . . . 17
6.1.10. Application of Measurement Methodology . . . . . . . . 17 6.1.10. Application of Measurement Methodology . . . . . . . . 18
7. Delay Variation Metrics and Statistics . . . . . . . . . . . . 17 7. Delay Variation Metrics and Statistics . . . . . . . . . . . . 18
7.1. Name: Type-P-One-way-pdv-refmin-Poisson/Periodic-Stream . 17 7.1. Name: Type-P-One-way-pdv-refmin-Poisson/Periodic-Stream . 18
7.1.1. Metric Parameters: . . . . . . . . . . . . . . . . . . 17 7.1.1. Metric Parameters: . . . . . . . . . . . . . . . . . . 18
7.1.2. Definition and Metric Units . . . . . . . . . . . . . 18 7.1.2. Definition and Metric Units . . . . . . . . . . . . . 19
7.1.3. Discussion and other details . . . . . . . . . . . . . 18 7.1.3. Discussion and other details . . . . . . . . . . . . . 19
7.1.4. Statistics: Mean, Variance, Skewness, Quanitle . . . . 18 7.1.4. Statistics: Mean, Variance, Skewness, Quanitle . . . . 19
7.1.5. Composition Functions: . . . . . . . . . . . . . . . . 19 7.1.5. Composition Functions: . . . . . . . . . . . . . . . . 20
7.1.6. Statement of Conjecture and Assumptions . . . . . . . 20 7.1.6. Statement of Conjecture and Assumptions . . . . . . . 21
7.1.7. Justification of the Composition Function . . . . . . 20 7.1.7. Justification of the Composition Function . . . . . . 21
7.1.8. Sources of Deviation from the Ground Truth . . . . . . 21 7.1.8. Sources of Deviation from the Ground Truth . . . . . . 22
7.1.9. Specific cases where the conjecture might fail . . . . 21 7.1.9. Specific cases where the conjecture might fail . . . . 22
7.1.10. Application of Measurement Methodology . . . . . . . . 21 7.1.10. Application of Measurement Methodology . . . . . . . . 22
8. Security Considerations . . . . . . . . . . . . . . . . . . . 21 8. Security Considerations . . . . . . . . . . . . . . . . . . . 22
8.1. Denial of Service Attacks . . . . . . . . . . . . . . . . 21 8.1. Denial of Service Attacks . . . . . . . . . . . . . . . . 22
8.2. User Data Confidentiality . . . . . . . . . . . . . . . . 21 8.2. User Data Confidentiality . . . . . . . . . . . . . . . . 22
8.3. Interference with the metrics . . . . . . . . . . . . . . 22 8.3. Interference with the metrics . . . . . . . . . . . . . . 23
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
10. Acknowlegements . . . . . . . . . . . . . . . . . . . . . . . 22 10. Acknowlegements . . . . . . . . . . . . . . . . . . . . . . . 23
11. Issues (Open and Closed) . . . . . . . . . . . . . . . . . . . 22 11. Issues (Open and Closed) . . . . . . . . . . . . . . . . . . . 23
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 24 12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 25
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 24 13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
13.1. Normative References . . . . . . . . . . . . . . . . . . . 24 13.1. Normative References . . . . . . . . . . . . . . . . . . . 25
13.2. Informative References . . . . . . . . . . . . . . . . . . 24 13.2. Informative References . . . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26
Intellectual Property and Copyright Statements . . . . . . . . . . 26
1. Contributors 1. Contributors
Thus far, the following people have contributed useful ideas, Thus far, the following people have contributed useful ideas,
suggestions, or the text of sections that have been incorporated into suggestions, or the text of sections that have been incorporated into
this memo: this memo:
- Phil Chimento <vze275m9@verizon.net> - Phil Chimento <vze275m9@verizon.net>
- Reza Fardid <RFardid@Covad.COM> - Reza Fardid <RFardid@Covad.COM>
skipping to change at page 5, line 13 skipping to change at page 6, line 13
[RFC2330] section 12), [RFC2330] section 12),
o a justification of the practical utility of the composition in o a justification of the practical utility of the composition in
terms of making accurate measurements of the metric on the path, terms of making accurate measurements of the metric on the path,
o a justification of the usefulness of the composition in terms of o a justification of the usefulness of the composition in terms of
making analysis of the path using A-frame concepts more effective, making analysis of the path using A-frame concepts more effective,
and and
o an analysis of how the conjecture could be incorrect. o an analysis of how the conjecture could be incorrect.
Also, [RFC2330] gives an example where a conjecture that the delay of Also, [RFC2330] gives an example using the conjecture that the delay
a path is very nearly the sum of the delays of the exchanges and of a path is very nearly the sum of the delays of the exchanges and
clouds of the corresponding path digest. This example is clouds of the corresponding path digest. This example is
particularly relevant to those who wish to assess the performance of particularly relevant to those who wish to assess the performance of
an Inter-domain path without direct measurement, and the performance an Inter-domain path without direct measurement, and the performance
estimate of the complete path is related to the measured results for estimate of the complete path is related to the measured results for
various sub-paths instead. various sub-paths instead.
Approximate functions between the sub-path and complete path metrics Approximate functions between the sub-path and complete path metrics
are useful, with knowledge of the circumstances where the are useful, with knowledge of the circumstances where the
relationships are/are not applicable. For example, we would not relationships are/are not applicable. For example, we would not
expect that delay singletons from each sub-path would sum to produce expect that delay singletons from each sub-path would sum to produce
skipping to change at page 6, line 8 skipping to change at page 7, line 8
policy, using its own measurement tools and methods, and using its policy, using its own measurement tools and methods, and using its
own measurement timing. Under the appropriate conditions, one can own measurement timing. Under the appropriate conditions, one can
combine the sub-path One-way metric results to estimate the complete combine the sub-path One-way metric results to estimate the complete
path One-way measurement metric with some degree of accuracy. path One-way measurement metric with some degree of accuracy.
3. Scope and Application 3. Scope and Application
3.1. Scope of work 3.1. Scope of work
For the primary IPPM metrics of Loss, Delay, and Delay Variation, For the primary IPPM metrics of Loss, Delay, and Delay Variation,
this memo gives a set of metrics for that can be composed from the this memo gives a set of metrics that can be composed from the same
same or similar sub-path metrics. This means that the composition or similar sub-path metrics. This means that the composition
function may utilize: function may utilize:
o the same metric for each sub-path; o the same metric for each sub-path;
o multiple metrics for each sub-path (possibly one that is the same o multiple metrics for each sub-path (possibly one that is the same
as the complete path metric); as the complete path metric);
o a single sub-path metrics that is different from the complete path o a single sub-path metric that is different from the complete path
metric; metric;
o different measurement techniques like active and passive o different measurement techniques like active and passive
(recognizing that PSAMP WG will define capabilities to sample (recognizing that PSAMP WG will define capabilities to sample
packets to support measurement). packets to support measurement).
3.2. Application 3.2. Application
The new composition framework [I-D.ietf-ippm-framework-compagg] The new composition framework [I-D.ietf-ippm-framework-compagg]
requires the specification of the applicable circumstances for each requires the specification of the applicable circumstances for each
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>>>>>>>>>>>>>>>>RESOLUTION: No and Yes. >>>>>>>>>>>>>>>>RESOLUTION: No and Yes.
12. Acknowledgements 12. Acknowledgements
13. References 13. References
13.1. Normative References 13.1. Normative References
[I-D.ietf-ippm-framework-compagg] [I-D.ietf-ippm-framework-compagg]
Morton, A., "Framework for Metric Composition", Morton, A., "Framework for Metric Composition",
draft-ietf-ippm-framework-compagg-06 (work in progress), draft-ietf-ippm-framework-compagg-07 (work in progress),
February 2008. October 2008.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis, [RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
"Framework for IP Performance Metrics", RFC 2330, "Framework for IP Performance Metrics", RFC 2330,
May 1998. May 1998.
[RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way [RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way
Delay Metric for IPPM", RFC 2679, September 1999. Delay Metric for IPPM", RFC 2679, September 1999.
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November 2002. November 2002.
[RFC4148] Stephan, E., "IP Performance Metrics (IPPM) Metrics [RFC4148] Stephan, E., "IP Performance Metrics (IPPM) Metrics
Registry", BCP 108, RFC 4148, August 2005. Registry", BCP 108, RFC 4148, August 2005.
13.2. Informative References 13.2. Informative References
[I-D.ietf-ippm-multimetrics] [I-D.ietf-ippm-multimetrics]
Stephan, E., Liang, L., and A. Morton, "IP Performance Stephan, E., Liang, L., and A. Morton, "IP Performance
Metrics (IPPM) for spatial and multicast", Metrics (IPPM) for spatial and multicast",
draft-ietf-ippm-multimetrics-07 (work in progress), draft-ietf-ippm-multimetrics-09 (work in progress),
June 2008. October 2008.
[Y.1540] ITU-T Recommendation Y.1540, "Internet protocol data [Y.1540] ITU-T Recommendation Y.1540, "Internet protocol data
communication service - IP packet transfer and communication service - IP packet transfer and
availability performance parameters", December 2002. availability performance parameters", December 2002.
[Y.1541] ITU-T Recommendation Y.1541, "Network Performance [Y.1541] ITU-T Recommendation Y.1541, "Network Performance
Objectives for IP-based Services", February 2006. Objectives for IP-based Services", February 2006.
Authors' Addresses Authors' Addresses
skipping to change at page 25, line 18 skipping to change at page 26, line 18
AT&T Labs AT&T Labs
200 Laurel Avenue South 200 Laurel Avenue South
Middletown,, NJ 07748 Middletown,, NJ 07748
USA USA
Phone: +1 732 420 1571 Phone: +1 732 420 1571
Fax: +1 732 368 1192 Fax: +1 732 368 1192
Email: acmorton@att.com Email: acmorton@att.com
URI: http://home.comcast.net/~acmacm/ URI: http://home.comcast.net/~acmacm/
Stephan Emile Emile Stephan
France Telecom Division R&D France Telecom Division R&D
2 avenue Pierre Marzin 2 avenue Pierre Marzin
Lannion, F-22307 Lannion, F-22307
France France
Phone: Phone:
Fax: +33 2 96 05 18 52 Fax: +33 2 96 05 18 52
Email: emile.stephan@orange-ftgroup.com Email: emile.stephan@orange-ftgroup.com
URI: URI:
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specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at
ietf-ipr@ietf.org.
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