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
	Status of this Memo		Status of this Memo
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	Copyright Notice		Copyright Notice
	Copyright (C) The IETF Trust (2007).		Copyright (C) The IETF Trust (2007).
	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
End of changes. 54 change blocks.
	117 lines changed or deleted		258 lines changed or added
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