draft-ietf-ippm-duplicate-01.txt   draft-ietf-ippm-duplicate-02.txt 
Network Working Group H. Uijterwaal Network Working Group H. Uijterwaal
Internet-Draft RIPE NCC Internet-Draft RIPE NCC
Intended status: Standards Track August 6, 2007
Expires: October 3, 2007 Expires: February 7, 2008
A One-Way Packet Duplication Metric for IPPM A One-Way Packet Duplication Metric for IPPM
draft-ietf-ippm-duplicate-01.txt draft-ietf-ippm-duplicate-02.txt
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Copyright Notice Copyright Notice
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Abstract Abstract
The IETF IPPM working group has defined a metric for packet loss. When a packet is sent from one host to the other, one normally
The packet loss metric quantifies the case where a packet that is expects that exactly one copy of the packet that was sent arrives at
sent, never arrives at its destination. However, the opposite is the destination. It is, however, possible that a packet is either
also possible: a packet is sent and arrives more than once. This lost or that multiple copies arrive.
document defines a metric to quantify these kinds of events.
In earlier work, the IPPM group defined a metric for packet loss.
This metric quantifies the case where a packet that is sent, never
arrives at its destination. In this memo, a metric for the opposite
case is defined: a packet is sent, but multiple copies arrive.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 4
1.2. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 4
2. A Singleton Definition for One-Way Packet Duplication . . . . 3 2. A Singleton Definition for one-way packet arrival . . . . . . 5
2.1. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Metrics Parameters . . . . . . . . . . . . . . . . . . . . 4 2.2. Metrics Parameters . . . . . . . . . . . . . . . . . . . . 5
2.3. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 4 2.3. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 5
2.4. Definition . . . . . . . . . . . . . . . . . . . . . . . . 4 2.4. Definition . . . . . . . . . . . . . . . . . . . . . . . . 5
2.5. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 4 2.5. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 5
2.6. Methodology . . . . . . . . . . . . . . . . . . . . . . . 4 2.6. Methodology . . . . . . . . . . . . . . . . . . . . . . . 6
2.7. Errors and uncertainties . . . . . . . . . . . . . . . . . 4 2.7. Errors and uncertainties . . . . . . . . . . . . . . . . . 6
2.8. Reporting the metric . . . . . . . . . . . . . . . . . . . 5 2.8. Reporting the metric . . . . . . . . . . . . . . . . . . . 6
3. A definition for Samples of One-way Packet Duplication . . . . 5 3. A Singleton Definition for one-way packet duplication . . . . 6
3.1. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 5 3.1. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 6
3.2. Metric Parameters . . . . . . . . . . . . . . . . . . . . 5 3.2. Metrics Parameters . . . . . . . . . . . . . . . . . . . . 6
3.3. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 5 3.3. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 6
3.4. Definition . . . . . . . . . . . . . . . . . . . . . . . . 5 3.4. Definition . . . . . . . . . . . . . . . . . . . . . . . . 7
3.5. Methodology . . . . . . . . . . . . . . . . . . . . . . . 5 3.5. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 7
3.6. Errors and uncertainties . . . . . . . . . . . . . . . . . 5 4. Definition for samples for one-way Packet Duplication . . . . 7
3.7. Reporting the metric . . . . . . . . . . . . . . . . . . . 6 4.1. Poisson Streams . . . . . . . . . . . . . . . . . . . . . 7
4. Some statistics definitions for One-way Duplication . . . . . 6 4.1.1. Metric Name . . . . . . . . . . . . . . . . . . . . . 7
4.1. Type-P-one-way-packet-duplication-average . . . . . . . . 6 4.1.2. Metric Parameters . . . . . . . . . . . . . . . . . . 7
4.2. Type-P-one-way-packet-duplication-rate . . . . . . . . . . 6 4.1.3. Metric Units . . . . . . . . . . . . . . . . . . . . . 7
4.3. Examples . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.1.4. Definition . . . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 4.1.5. Methodology . . . . . . . . . . . . . . . . . . . . . 8
6. Relation with Y.1540 . . . . . . . . . . . . . . . . . . . . . 8 4.1.6. Errors and uncertainties . . . . . . . . . . . . . . . 8
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 4.1.7. Reporting the metric . . . . . . . . . . . . . . . . . 8
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8 4.2. Periodic Streams . . . . . . . . . . . . . . . . . . . . . 8
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2.1. Metric Name . . . . . . . . . . . . . . . . . . . . . 8
9.1. Normative References . . . . . . . . . . . . . . . . . . . 8 4.2.2. Metric Parameters . . . . . . . . . . . . . . . . . . 8
9.2. Informative References . . . . . . . . . . . . . . . . . . 8 4.2.3. Metric Units . . . . . . . . . . . . . . . . . . . . . 8
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.2.4. Definition . . . . . . . . . . . . . . . . . . . . . . 8
Intellectual Property and Copyright Statements . . . . . . . . . . 10 4.2.5. Methodology . . . . . . . . . . . . . . . . . . . . . 9
4.2.6. Errors and uncertainties . . . . . . . . . . . . . . . 9
4.2.7. Reporting the metric . . . . . . . . . . . . . . . . . 9
5. Some statistics definitions for one-way Duplication . . . . . 9
5.1. Type-P-one-way-packet-duplication-fraction . . . . . . . . 9
5.2. Type-P-one-way-replicated-packet-rate . . . . . . . . . . 9
5.3. Examples . . . . . . . . . . . . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 11
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
9.1. Normative References . . . . . . . . . . . . . . . . . . . 12
9.2. Informative References . . . . . . . . . . . . . . . . . . 12
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 12
Intellectual Property and Copyright Statements . . . . . . . . . . 13
1. Introduction 1. Introduction
This document defines a metric for one-way packet duplication across This document defines a metric for one-way packet duplication across
Internet paths. It builds on the IPPM Framework document [RFC2330]; Internet paths. It builds on the IPPM Framework document [RFC2330];
the reader is assumed to be familiar with that document. the reader is assumed to be familiar with that document.
This document follows the same structure as the document for One-way This document follows the same structure as the document for one-way
Packet Loss [RFC2680]; the reader is assumed to be familiar with that Packet Loss [RFC2680]; the reader is assumed to be familiar with that
document as well. document as well.
The structure of this memo is as follows: The structure of this memo is as follows:
o First, a singleton metric, called Type-P-One-way-packet- o First, a singleton metric, called Type-P-one-way-packet-arrival-
duplication, is introduced to describe a single instance of packet count, is introduced to measure the number of arriving packets for
each packet sent.
o Then, a singleton metric, called Type-P-one-way-packet-
duplication, is defined to describe a single instance of packet
duplication. duplication.
o Then, this singleton metric is used to define a sample, Type-P- o Next, this singleton metric is used to define samples, Type-P-one-
One-way-Packet-Duplication-Poisson-Stream, is introduced to way-Packet-Duplication-Poisson-Stream and Type-P-one-way-Packet-
measure duplication in a series of packets sent. Duplication-Periodic-Stream. These are introduced to measure
o Finally, a method to summarise the properties of this sample is duplication in a series of packets sent with either Poisson-
distributed [RFC2680] or periodic [RFC3432] intervals between the
packets.
o Finally, a method to summarise the properties of these samples are
introduced. introduced.
1.1. Requirements notation 1.1. Requirements notation
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 [RFC2119]. document are to be interpreted as described in [RFC2119].
1.2. Motivation 1.2. Motivation
The IETF IPPM working group has defined a metric for packet loss When a packet is sent from one host to the other, one normally
[RFC2680]. The packet loss metric quantifies the case where a packet expects that exactly one copy of the packet that was sent arrives at
that is sent, never arrives at its destination. However, the the destination. It is, however, possible that a packet is either
opposite is also possible: a packet is sent and arrives more than lost or that multiple copies arrive.
once. This document defines a metric to quantify these kinds of
events. In earlier work, the IPPM group defined a metric for packet loss
[RFC2680]. This metric quantifies the case where a packet that is
sent, never arrives at its destination. In this memo, a metric for
the opposite case is defined: a packet is sent, but multiple copies
arrive.
As this document describes a case similar to the one discussed in As this document describes a case similar to the one discussed in
[RFC2680], all considerations from that document on timing and [RFC2680], all considerations from that document on timing and
accuracy apply. accuracy apply.
2. A Singleton Definition for One-Way Packet Duplication 2. A Singleton Definition for one-way packet arrival
2.1. Metric Name 2.1. Metric Name
Type-P-One-way-Packet-Duplication Type-P-one-way-packet-arrival-count
2.2. Metrics Parameters 2.2. Metrics Parameters
o Src, the IP address of a host o Src, the IP address of a host
o Dst, the IP address of a host o Dst, the IP address of a host
o T, a time o T, a time
o T0, a time o T0, a time
2.3. Metric Units 2.3. Metric Units
A positive integer number An integer number
2.4. Definition 2.4. Definition
The value of a Type-P-One-way-Packet-Duplication is a positive Two packets are considered identical when were sent by one and the
same host and contain identical information fields. The recipient
thus could take either packet and use it in an application, the other
copy would not contain any additional information.
The IP headers do not necessarily have to be identical. This can
happen, for example, if two packets take a different route resulting
in a different TTL.
The value of a Type-P-one-way-packet-arrival-count is a positive
integer number indicating the number of (uncorrupted and identical) integer number indicating the number of (uncorrupted and identical)
copies received by dst in the interval [T, T+T0] for a packet sent by copies received by dst in the interval [T, T+T0] for a packet sent by
src at time T. src at time T.
If a packet is sent, but it is lost or does not arrive in the If a packet is sent, but it is lost or does not arrive in the
interval [T, T+T0], then the metric is undefined. interval [T, T+T0], then the metric is undefined. Applications MAY
report an "impossible" value (for example, -1) to indicate this
condition instead of undefined.
If a packet is fragmented during transport and if, for whatever
reason, re-assembly does not occur, then the packet will be deemed
lost. It is thus not included in the Type-P-one-way-packet-arrival-
count.
2.5. Discussion 2.5. Discussion
This metric counts the number of packets arriving for each packet This metric counts the number of packets arriving for each packet
sent. The time-out value T0 SHOULD be set to a value when the sent. The time-out value T0 SHOULD be set to a value when the
application could potentially still use the packet and not discard it application could potentially still use the packet and not discard it
automatically. automatically.
The metric only counts packets that are not corrupted during The metric only counts packets that are not corrupted during
transmission and may have been resent automatically by lower layers transmission and may have been resent automatically by lower layers
or intermediate devices. Packets that were corrupted during or intermediate devices. Packets that were corrupted during
transmission but nevertheless still arrived at dst are not counted. transmission but nevertheless still arrived at dst are not counted.
If a packet is fragmented and one of the fragments arrives more than Because of the definition of duplication (identical information
once, then the packet is counted as duplicated. fields), active measurement systems MUST NOT send multiple packets
with identical information fields, in order to avoid that all packets
will be declared duplicates.
2.6. Methodology 2.6. Methodology
Refer to section 2.6 of [RFC2680] (We may cut and paste relevant text The basic technique to measure this metrics follows the methodology
into this document later). described in [RFC2680], section 2.6, with one exception.
[RFC2680] does specify that the receiving host should be able to
receive multiple copies of a single packet, as it only needs one copy
to determine the metrics. Implementations for this metric should
obviously be capable to receive multiple copies.
2.7. Errors and uncertainties 2.7. Errors and uncertainties
Refer to section 2.7 of [RFC2680] (We may cut and paste relevant text Refer to section 2.7 of [RFC2680]
into this document later).
2.8. Reporting the metric 2.8. Reporting the metric
Refer to section 2.8 of [RFC2680] (We may cut and paste relevant text Refer to section 2.8 of [RFC2680]
into this document later).
3. A definition for Samples of One-way Packet Duplication 3. A Singleton Definition for one-way packet duplication
3.1. Metric Name 3.1. Metric Name
Type-P-One-way-Packet-Duplication-Poisson-Stream Type-P-one-way-packet-duplication
3.2. Metric Parameters 3.2. Metrics Parameters
o Src, the IP address of a host
o Dst, the IP address of a host
o T, a time
o T0, a time
3.3. Metric Units
An integer number.
3.4. Definition
The value of a Type-P-one-way-packet-duplication is a positive
integer number indicating the number of (uncorrupted and identical)
additional copies of an individual packet received by dst in the
interval [T, T+T0] sent by src at time T.
If a packet is sent and only one copy arrives in the interval [T,
T+T0], then the metric is 0. If no copy arrives in this interval, ,
then the metric is undefined. Applications MAY report an
"impossible" value (for example, -1) to indicate this condition.
3.5. Discussion
This metric is equal to
Type-P-one-way-packet-arrival-count - 1
This metric is expected to be used for applications that need to know
duplication for an individual packet. All considerations regarding
methodology, errors and reporting from the previous section apply.
4. Definition for samples for one-way Packet Duplication
4.1. Poisson Streams
4.1.1. Metric Name
Type-P-one-way-Packet-Duplication-Poisson-Stream
4.1.2. Metric Parameters
o Src, the IP address of a host o Src, the IP address of a host
o Dst, the IP address of a host o Dst, the IP address of a host
o Ts, a time o Ts, a time
o T0, a time o T0, a time
o Tf, a time o Tf, a time
o lamba, a rate in reciprocal seconds o lambda, a rate in reciprocal seconds
3.3. Metric Units 4.1.3. Metric Units
A sequence of pairs; the elements of each pair are: A sequence of pairs; the elements of each pair are:
o T, a time o T, a time
o Type-P-One-way-Packet-Duplication for the packet sent at T. o Type-P-one-way-packet-arrival-count for the packet sent at T.
3.4. Definition 4.1.4. Definition
Given Ts, Tf and lambda, we compute a pseudo-random Poisson process Given Ts, Tf and lambda, we compute a pseudo-random Poisson process
beginning at or before Ts, with average rate lambda and ending at or beginning at or before Ts, with average rate lambda and ending at or
after Tf. Those time values greater than or equal to Ts, and less after Tf. Those time values greater than or equal to Ts, and less
than or equal to Tf are then selected. At each of the times in this than or equal to Tf are then selected. At each of the times in this
process, we obtain the value of Type-P-One-way-Packet-Duplication. process, we obtain the value of Type-P-one-way-packet-arrival-count.
the value of the sample is the sequence made up of the resulting The value of the sample is the sequence made up of the resulting
{time, duplication} pairs. If there are no such pairs, the sequence {time, duplication} pairs. If there are no such pairs, the sequence
is of length zero and the sample is said to be empty. is of length zero and the sample is said to be empty.
3.5. Methodology 4.1.5. Methodology
Refer to [RFC2680] Refer to [RFC2680], section 3.6.
3.6. Errors and uncertainties 4.1.6. Errors and uncertainties
Refer to [RFC2680] Refer to [RFC2680], section 3.7.
3.7. Reporting the metric 4.1.7. Reporting the metric
Refer to [RFC2680] Refer to [RFC2680], section 3.8.
4. Some statistics definitions for One-way Duplication 4.2. Periodic Streams
4.1. Type-P-one-way-packet-duplication-average 4.2.1. Metric Name
This statistics gives an estimate of the fraction of additional Type-P-one-way-Packet-Duplication-Poisson-Stream
packets that arrived in a stream.
Given a Type-P-One-way-Packet-Duplication-Poisson-Stream, one first 4.2.2. Metric Parameters
removes all values of Type-P-One-way-Packet-Duplication which are
o Src, the IP address of a host
o Dst, the IP address of a host
o Ts, a time
o T0, a time
o Tf, a time
o lambda, a rate in reciprocal seconds
4.2.3. Metric Units
A sequence of pairs; the elements of each pair are:
o T, a time
o Type-P-one-way-packet-arrival-count for the packet sent at T.
4.2.4. Definition
At time Ts, we start sending packets with a constant rate lambda,
until time Tf. For each packet sent, we obtain the value of Type-P-
one-way-packet-arrival-count. The value of the sample is the
sequence made up of the resulting {time, duplication} pairs. If
there are no such pairs, the sequence is of length zero and the
sample is said to be empty.
4.2.5. Methodology
Refer to [RFC2680], section 4.5.
4.2.6. Errors and uncertainties
Refer to [RFC2680], section 4.6.
4.2.7. Reporting the metric
Refer to [RFC2680], section 4.7.
5. Some statistics definitions for one-way Duplication
Note: the statistics described in this section can be used for both
Type-P-one-way-Packet-Duplication-Poisson-Stream and Type-P-one-way-
Packet-Duplication-Periodic-Stream. The application SHOULD report
which sample was used as input.
5.1. Type-P-one-way-packet-duplication-fraction
This statistics gives the fraction of additional packets that arrived
in a stream.
Given a Type-P-one-way-Packet-Duplication-Poisson-Stream, one first
removes all values of Type-P-one-way-Packet-Duplication which are
undefined. For the remaining pairs in the stream, one calculates: undefined. For the remaining pairs in the stream, one calculates:
(Sum Type-P-One-Way-Packet-Duplication/Number of pairs left) - 1 (In (Sum Type-P-one-Way-packet-arrival-count/Number of pairs left) - 1
other words, #packets received/(#sent and not lost).) (In other words, #packets received/(#sent and not lost).)
The number can be expressed as a percentage. The number can be expressed as a percentage.
Note: this statistics is the equivalent of the Y.1540 IPDR [Y1540] Note: this statistics is the equivalent of the Y.1540 IPDR [Y1540]
4.2. Type-P-one-way-packet-duplication-rate 5.2. Type-P-one-way-replicated-packet-rate
This statistics gives an estimate of the fraction of packets that was This statistics gives the fraction of packets that was duplicated
duplicated (one or more times) in a stream. (one or more times) in a stream.
Given a Type-P-One-way-Packet-Duplication-Poisson-Stream, one first Given a Type-P-one-way-Packet-Duplication-Poisson-Stream, one first
removes all values of Type-P-One-way-Packet-Duplication which are removes all values of Type-P-one-way-packet-arrival-count which are
undefined. For the remaining pairs in the stream, one counts the undefined. For the remaining pairs in the stream, one counts the
number of pairs with Type-P-One-Way-Packet-Duplication greater than number of pairs with Type-P-one-Way-packet-arrival-count greater than
1. Then one calculates the fraction of packets that meet this 1. Then one calculates the fraction of packets that meet this
criterium as a fraction of the total. (In other words: # with criterium as a fraction of the total. (In other words: # with
duplication/(#sent and not lost).). duplication/(#sent and not lost).).
The number can be expressed as a percentage. The number can be expressed as a percentage.
Note: this statistics is the equivalent of the Y.1540 RIPR [Y1540] Note: this statistics is the equivalent of the Y.1540 RIPR [Y1540]
4.3. Examples 5.3. Examples
Consider a stream of 4 packets, sent as: Consider a stream of 4 packets, sent as:
(1, 2, 3, 4) (1, 2, 3, 4)
and arriving as: and arriving as:
o Case 1: (1, 2, 3, 4) o Case 1: (1, 2, 3, 4)
o Case 2: (1, 1, 2, 2, 3, 3, 4, 4) o Case 2: (1, 1, 2, 2, 3, 3, 4, 4)
o Case 3: (1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4) o Case 3: (1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4)
o Case 4: (1, 1, 1, 2, 3, 3, 3, 4) o Case 4: (1, 1, 1, 2, 3, 3, 3, 4)
Case 1: No packets are duplicated in a stream and both the Type-P- Case 1: No packets are duplicated in a stream and both the Type-P-
one-way-packet-duplication-average and the type-P-one-way-packet- one-way-packet-duplication-fraction and the type-P-one-way-packet-
duplication-rate are 0. replicated-packet-rate are 0.
Case 2: Every packet is duplicated once and the Type-P-one-way- Case 2: Every packet is duplicated once and the Type-P-one-way-
packet-duplication-average is 100%. The type-P-one-way-packet- packet-duplication-fraction is 100%. The type-P-one-way-replicated-
duplication-rate is 100% too. packet-rate is 100% too.
Case 3: Every packet is duplicated twice, so the Type-P-one-way- Case 3: Every packet is duplicated twice, so the Type-P-one-way-
packet-duplication-average is 200%. The type-P-one-way-packet- packet-duplication-fraction is 200%. The type-P-one-way-replicated-
duplication-rate is still 100%. packet-rate is still 100%.
Case 4: Half the packets are duplicated twice and the other half are Case 4: Half the packets are duplicated twice and the other half are
not duplicated. The Type-P-one-way-packet-duplication-average is not duplicated. The Type-P-one-way-packet-duplication-fraction is
again 100% and this number does not show the difference with case 2. again 100% and this number does not show the difference with case 2.
However, the type-P-one-way-packet-duplication-rate is 50% in this However, the type-P-one-way-packet-replicated-packet-rate is 50% in
case and 100% in case 2. this case and 100% in case 2.
However, the type-P-one-way-packet-duplication-rate will not show the However, the type-P-one-way-packet-duplication-rate will not show the
difference between case 2 and 3. For this, one has to look at the difference between case 2 and 3. For this, one has to look at the
Type-P-one-way-packet-duplication-average. Type-P-one-way-packet-duplication-fraction.
5. Security Considerations 6. Security Considerations
Conducting Internet measurements raises both security and privacy Conducting Internet measurements raises both security and privacy
concerns. This memo does not specify an implementation of the concerns. This memo does not specify an implementation of the
metrics, so it does not directly affect the security of the Internet metrics, so it does not directly affect the security of the Internet
nor of applications which run on the Internet. However, nor of applications which run on the Internet. However,
implementations of these metrics must be mindful of security and implementations of these metrics must be mindful of security and
privacy concerns. privacy concerns.
There are two types of security concerns: potential harm caused by There are two types of security concerns: potential harm caused by
the measurements, and potential harm to the measurements. The the measurements, and potential harm to the measurements. The
skipping to change at page 8, line 18 skipping to change at page 11, line 34
rate will be artificially lowered. Therefore, the measurement rate will be artificially lowered. Therefore, the measurement
methodologies SHOULD include appropriate techniques to reduce the methodologies SHOULD include appropriate techniques to reduce the
probability measurement traffic can be distinguished from "normal" probability measurement traffic can be distinguished from "normal"
traffic. Authentication techniques, such as digital signatures, may traffic. Authentication techniques, such as digital signatures, may
be used where appropriate to guard against injected traffic attacks. be used where appropriate to guard against injected traffic attacks.
The privacy concerns of network measurement are limited by the active The privacy concerns of network measurement are limited by the active
measurements described in this memo. Unlike passive measurements, measurements described in this memo. Unlike passive measurements,
there can be no release of existing user data. there can be no release of existing user data.
6. Relation with Y.1540
Do we need this?
7. IANA Considerations 7. IANA Considerations
This document makes no requests from the IANA. This section can be IANA is asked to add this metrics to the IANA IP Performance Metrics
removed upon publication as a RFC. (IPPM) Metrics Registry, see [RFC4148]. This section can be removed
after this has been done and upon publication as a RFC.
8. Acknowledgements 8. Acknowledgements
The idea to write this draft came up in a meeting with Al Morton, The idea to write this draft came up in a meeting with Al Morton,
Stanislav Shalunov, Emile Stephan and the author. Stanislav Shalunov, Emile Stephan and the author, on the IPPM
reporting draft.
This document relies heavily on [RFC2680] and the author likes to This document relies heavily on [RFC2680] and the author likes to
thank the authors of that document for writing it. thank the authors of that document for writing it.
Finally, thanks are due to ... for their comments. Finally, thanks are due to ... for their comments.
9. References 9. References
9.1. Normative References 9.1. Normative References
skipping to change at page 9, line 9 skipping to change at page 12, line 21
9.2. Informative References 9.2. Informative References
[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.
[RFC2680] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way [RFC2680] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way
Packet Loss Metric for IPPM", RFC 2680, September 1999. Packet Loss Metric for IPPM", RFC 2680, September 1999.
[RFC3432] Raisanen, V., Grotefeld, G., and A. Morton, "Network
performance measurement with periodic streams", RFC 3432,
November 2002.
[RFC4148] Stephan, E., "IP Performance Metrics (IPPM) Metrics
Registry", BCP 108, RFC 4148, August 2005.
[Y1540] A. Morton, "Y.1540", July 2003. [Y1540] A. Morton, "Y.1540", July 2003.
Author's Address Author's Address
Henk Uijterwaal Henk Uijterwaal
RIPE NCC RIPE NCC
Singel 258 Singel 258
1016 AB Amsterdam 1016 AB Amsterdam
The Netherlands The Netherlands
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