 1/draftietfippmmultimetrics05.txt 20080215 15:12:19.000000000 +0100
+++ 2/draftietfippmmultimetrics06.txt 20080215 15:12:19.000000000 +0100
@@ 1,21 +1,21 @@
Network Working Group E. Stephan
InternetDraft France Telecom
Intended status: Informational L. Liang
Expires: May 21, 2008 University of Surrey
+Expires: August 17, 2008 University of Surrey
A. Morton
AT&T Labs
 November 18, 2007
+ February 14, 2008
IP Performance Metrics (IPPM) for spatial and multicast
 draftietfippmmultimetrics05
+ draftietfippmmultimetrics06
Status of this Memo
By submitting this InternetDraft, each author represents that any
applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79.
InternetDrafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
@@ 26,95 +26,97 @@
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use InternetDrafts as reference
material or to cite them other than as "work in progress."
The list of current InternetDrafts can be accessed at
http://www.ietf.org/ietf/1idabstracts.txt.
The list of InternetDraft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
 This InternetDraft will expire on May 21, 2008.
+ This InternetDraft will expire on August 17, 2008.
Copyright Notice
 Copyright (C) The IETF Trust (2007).
+ Copyright (C) The IETF Trust (2008).
Abstract
The IETF IP Performance Metrics (IPPM) working group has standardized
metrics for measuring endtoend performance between two points.
This memo defines two new categories of metrics that extend the
coverage to multiple measurement points. It defines spatial metrics
for measuring the performance of segments of a source to destination
path, and metrics for measuring the performance between a source and
many destinations in multiparty communications (e.g., a multicast
tree).
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1. Path Digest Hosts . . . . . . . . . . . . . . . . . . . . 6
2.2. Multiparty metric . . . . . . . . . . . . . . . . . . . . 6
2.3. Spatial metric . . . . . . . . . . . . . . . . . . . . . . 6
2.4. Onetogroup metric . . . . . . . . . . . . . . . . . . . 6
 2.5. Points of interest . . . . . . . . . . . . . . . . . . . . 6
+ 2.5. Points of interest . . . . . . . . . . . . . . . . . . . . 7
2.6. Reference point . . . . . . . . . . . . . . . . . . . . . 8
2.7. Vector . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.8. Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3. Motivations . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1. Motivations for spatial metrics . . . . . . . . . . . . . 9
3.2. Motivations for Onetogroup metrics . . . . . . . . . . . 10
3.3. Discussion on Grouptoone and Grouptogroup metrics . . 11
4. Spatial vectors metrics definitions . . . . . . . . . . . . . 11
4.1. A Definition for Spatial Oneway Delay Vector . . . . . . 12
4.2. A Definition for Spatial Oneway Packet Loss Vector . . . 13
4.3. A Definition for Spatial Oneway Ipdv Vector . . . . . . . 15
 4.4. Spatial Methodology . . . . . . . . . . . . . . . . . . . 17
 5. Spatial Segments metrics definitions . . . . . . . . . . . . . 19
+ 4.4. Spatial Methodology . . . . . . . . . . . . . . . . . . . 16
+ 5. Spatial Segments metrics definitions . . . . . . . . . . . . . 18
5.1. A Definition of a sample of Oneway Delay of a segment
 of the path . . . . . . . . . . . . . . . . . . . . . . . 19
+ of the path . . . . . . . . . . . . . . . . . . . . . . . 18
5.2. A Definition of a sample of Packet Loss of a segment
of the path . . . . . . . . . . . . . . . . . . . . . . . 20
 5.3. A Definition of a sample of Oneway Ipdv of a segment
 of the path . . . . . . . . . . . . . . . . . . . . . . . 23
 6. Onetogroup metrics definitions . . . . . . . . . . . . . . . 23
 6.1. A Definition for onetogroup Oneway Delay . . . . . . . 23
 6.2. A Definition for onetogroup Oneway Packet Loss . . . . 24
 6.3. A Definition for onetogroup Oneway Ipdv . . . . . . . . 25
 7. OnetoGroup Sample Statistics . . . . . . . . . . . . . . . . 26
 7.1. Discussion on the Impact of packet loss on statistics . . 29
 7.2. General Metric Parameters . . . . . . . . . . . . . . . . 30
 7.3. OnetoGroup oneway Delay Statistics . . . . . . . . . . 31
 7.4. OnetoGroup oneway Loss Statistics . . . . . . . . . . . 33
 7.5. OnetoGroup oneway Delay Variation Statistics . . . . . 35
 8. Measurement Methods: Scaleability and Reporting . . . . . . . 35
 8.1. Computation methods . . . . . . . . . . . . . . . . . . . 36
 8.2. Measurement . . . . . . . . . . . . . . . . . . . . . . . 37
 8.3. Effect of Time and Space Aggregation Order on Stats . . . 37
 9. Manageability Considerations . . . . . . . . . . . . . . . . . 39
 9.1. Reporting spatial metric . . . . . . . . . . . . . . . . . 39
 9.2. Reporting Onetogroup metric . . . . . . . . . . . . . . 40
 9.3. Metric identification . . . . . . . . . . . . . . . . . . 41
 9.4. Reporting data model . . . . . . . . . . . . . . . . . . . 41
 10. Open issues . . . . . . . . . . . . . . . . . . . . . . . . . 44
 11. Security Considerations . . . . . . . . . . . . . . . . . . . 45
 11.1. Spatial metrics . . . . . . . . . . . . . . . . . . . . . 45
 11.2. onetogroup metric . . . . . . . . . . . . . . . . . . . 45
 12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 45
 13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 46
 14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 51
 14.1. Normative References . . . . . . . . . . . . . . . . . . . 51
 14.2. Informative References . . . . . . . . . . . . . . . . . . 51
 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 52
 Intellectual Property and Copyright Statements . . . . . . . . . . 54
+ 5.3. A Definition of a sample of ipdv of a segment using
+ the previous packet selection function . . . . . . . . . . 22
+ 5.4. A Definition of a sample of ipdv of a segment using
+ the minimum delay selection function . . . . . . . . . . . 24
+ 6. Onetogroup metrics definitions . . . . . . . . . . . . . . . 25
+ 6.1. A Definition for Onetogroup Oneway Delay . . . . . . . 26
+ 6.2. A Definition for Onetogroup Oneway Packet Loss . . . . 26
+ 6.3. A Definition for Onetogroup Oneway Ipdv . . . . . . . . 27
+ 7. OnetoGroup Sample Statistics . . . . . . . . . . . . . . . . 28
+ 7.1. Discussion on the Impact of packet loss on statistics . . 31
+ 7.2. General Metric Parameters . . . . . . . . . . . . . . . . 32
+ 7.3. OnetoGroup oneway Delay Statistics . . . . . . . . . . 33
+ 7.4. OnetoGroup oneway Loss Statistics . . . . . . . . . . . 36
+ 7.5. OnetoGroup oneway Delay Variation Statistics . . . . . 38
+ 8. Measurement Methods: Scalability and Reporting . . . . . . . . 38
+ 8.1. Computation methods . . . . . . . . . . . . . . . . . . . 39
+ 8.2. Measurement . . . . . . . . . . . . . . . . . . . . . . . 40
+ 8.3. Effect of Time and Space Aggregation Order on Stats . . . 40
+ 9. Manageability Considerations . . . . . . . . . . . . . . . . . 42
+ 9.1. Reporting spatial metric . . . . . . . . . . . . . . . . . 42
+ 9.2. Reporting Onetogroup metric . . . . . . . . . . . . . . 43
+ 9.3. Metric identification . . . . . . . . . . . . . . . . . . 44
+ 9.4. Reporting data model . . . . . . . . . . . . . . . . . . . 44
+ 10. Open issues . . . . . . . . . . . . . . . . . . . . . . . . . 47
+ 11. Security Considerations . . . . . . . . . . . . . . . . . . . 47
+ 11.1. Spatial metrics . . . . . . . . . . . . . . . . . . . . . 48
+ 11.2. onetogroup metric . . . . . . . . . . . . . . . . . . . 48
+ 12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 48
+ 13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 48
+ 14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 54
+ 14.1. Normative References . . . . . . . . . . . . . . . . . . . 54
+ 14.2. Informative References . . . . . . . . . . . . . . . . . . 55
+ Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 55
+ Intellectual Property and Copyright Statements . . . . . . . . . . 57
1. Introduction
The IP Performance Metrics (IPPM) WG has defined a framework for
metric definitions and endtoend, or source to destination
measurements:
o A general framework for defining performance metrics, described in
the Framework for IP Performance Metrics [RFC2330];
@@ 162,32 +164,37 @@
be introduced to divide an endtoend TypePOnewayPacketLoss
[RFC2680] in a spatial sequence of packet loss metrics.
o Using the TypePSpatialOnewayDelayVector metric, a 'vector',
called TypePSpatialOnewayipdvVector, will be introduced to
divide an endtoend TypePOnewayipdv in a spatial sequence of
ipdv metrics.
o Using the TypePSpatialOnewayDelayVector metric, a 'sample',
called TypePSegmentOnewayDelayStream, will be introduced to
 collect a nested set of oneway delay metrics between the source,
 intermediate points of interest, and the destination;
+ collect oneway delay metrics over time between two points of
+ interest of the path;
o Using the TypePSpatialPacketLossVector metric, a 'sample',
called TypePSegmentPacketLossStream, will be introduced to
 collect a nested set of packet loss metrics between the source,
 intermediate points of interest, and the destination;
+ collect packet loss metrics over time between two points of
+ interest of the path;
 o Using the TypePSpatialipdvVector metric, a 'sample', called
 TypePSegmentipdvStream, will be introduced to collect a nested
 set of ipdv metrics between the source, intermediate points of
 interest, and the destination;
+ o Using the TypePSpatialOnewayDelayVector metric, a 'sample',
+ called TypePSegmentipdvprevStream, will be introduced to
+ compute ipdv metrics over time between two points of interest of
+ the path using the previous packet selection function;
+
+ o Using the TypePSpatialOnewayDelayVector metric, a 'sample',
+ called TypePSegmentipdvminStream, will be introduced to
+ compute ipdv metrics over time between two points of interest of
+ the path using the shortest delay selection function;
Note that all these metrics are based on observations of packets
dedicated to testing, a process which is called Active measurement.
Purely passive spatial measurement (for example, a spatial metric
based on the observation of user traffic) is beyond the scope of this
document and the current IPPM charter.
Next, this memo defines onetogroup metrics.
o Using one test packet sent from one sender to a group of
@@ 230,41 +237,41 @@
where ha is the source and < hb, hc, ..., hn > are the destinations,
then measurements may be conducted between < ha, hb>, < ha, hc>, ...,
.
For the purposes of this memo (reflecting the scope of a single
source), the only multiparty metrics are onetogroup metrics.
2.3. Spatial metric
A metric is said to be spatial if one of the hosts (measurement
 collection points) involved is neither the source nor the destination
+ collection points) involved is neither the source nor a destination
of the measured packet.
2.4. Onetogroup metric
A metric is said to be onetogroup if the measured packet is sent by
one source and (potentially) received by several destinations. Thus,
the topology of the communication group can be viewed as a centre
distributed or serverclient topology with the source as the centre/
server in the topology.
2.5. Points of interest
Points of interest are the hosts* (as per RFC2330 definition, that
includes routing nodes) that are measurement collection points, a
subset of the set of hosts involved in the delivery of the packets
(in addition to the source itself). Note that the points of interest
are a possibly arbitrary subset of all the hosts involved in the
path.
 Points of interest of Onetogroup metrics are the intended
+ Points of interest of onetogroup metrics are the intended
destination hosts for packets from the source (in addition to the
source itself).
Src Recv
`. ,.
`. ,' `...... 1
`. ; :
`. ; :
; :... 2
 
@@ 309,42 +316,42 @@
calculations will be carried out. A centre/server in the
multimetrics measurement that is controlled by a network operator is
a good example of a reference point, where measurement data can be
collected for further processing. However, the actual measurements
have to be carried out at all points of interest.
2.7. Vector
A Vector is a set of singletons, which are a set of results of the
observation of the behaviour of the same packet at different places
 of a network at different times. For instance, if Oneway delay
+ of a network at different times. For instance, if oneway delay
singletons observed at N receivers for Packet P sent by the source
Src are dT1, dT2,..., dTN, it can be say that a vector V with N
elements can be organized as {dT1, dT2,..., dTN}. The elements in
one vector are singletons distinct with each other in terms of both
measurement point and sending time. Given the vector V as an
example, the element dT1 is distinct from all others as the singleton
at receiver 1 in response to a packet sent from the source at time
T1. The complete Vector gives information over the dimension of
space.
2.8. Matrix
Several vectors form a Matrix, which contains results observed in a
 sampling interval at different places in a network at different time.
 For instance, given Oneway delay vectors V1={dT11, dT12,..., dT1N},
 V2={dT21, dT22,..., dT2N},..., Vm={dTm1, dTm2,..., dTmN} for Packet
 P1, P2,...,Pm, we can have a Oneway delay Matrix {V1, V2,...,Vm}.
 Additional to the information given by a Vector, a Matrix is more
 powerful to present network performance in both space and time
 dimensions. It normally corresponds to a sample in simple pointto
 point measurement.
+ sampling interval at different places in a network at different
+ times. For instance, given Oneway delay vectors V1={dT11, dT12,...,
+ dT1N}, V2={dT21, dT22,..., dT2N},..., Vm={dTm1, dTm2,..., dTmN} for
+ Packet P1, P2,...,Pm, we can have a Oneway delay Matrix {V1,
+ V2,...,Vm}. Additional to the information given by a Vector, a
+ Matrix is more powerful to present network performance in both space
+ and time dimensions. It normally corresponds to a sample in simple
+ pointtopoint measurement.
The relation among Singleton, Vector and Matrix can be shown in the
following Figure 3.
Point of Singleton
interest / Samples
,. ^ /
/ R1..... / R1dT1 R1dT2 R1dT3 ... R3dTk \
/ \   
; R2........  R2dT1 R2dT2 R2dT3 ... R3dTk 
@@ 380,21 +387,21 @@
o Traffic engineering and troubleshooting applications benefit from
spatial views of oneway delay and ipdv consumption, and
identification of the location of the lost of packets.
o Monitoring the performance of a multicast tree composed of MPLS
pointtomultipoint and interdomain communication require spatial
decomposition of the oneway delay, ipdv, and packet loss.
o Composition of metrics [ID.ietfippmspatialcomposition] is
needed to help measurement systems reach large scale coverage.
 Spatial measure typically give the individual performance of an
+ Spatial measures typically give the individual performance of an
intra domain segment and provide an elementary piece of
information needed to estimate interdomain performance based on
composition of metrics.
3.2. Motivations for Onetogroup metrics
While the nodetonode based spatial measures can provide very useful
data in the view of each connection, we also need measures to present
the performance of a multiparty communication topology. A simple
oneway metric cannot completely describe the multiparty situation.
@@ 413,21 +420,21 @@
o For designing and engineering multicast trees and MPLS pointto
multipoint LSP;
o For evaluating and controlling of the quality of the multicast
services;
o For controlling the performance of the inter domain multicast
services;
o For presenting and evaluating the performance requirements for
 multiparty communications.
+ multiparty communications and overlay multicast.
To understand the packet transfer performance between one source and
any one receiver in the multiparty communication group, we need to
collect instantaneous endtoend metrics, or singletons. It will
give a very detailed insight into each branch of the multicast tree
in terms of endtoend absolute performance. This detail can provide
clear and helpful information for engineers to identify the subpath
with problems in a complex multiparty routing tree.
The onetogroup metrics described in this memo introduce the
@@ 435,21 +442,21 @@
the performance delivered to a group of users who are receiving
packets from the same source. The concept extends the "path" in the
oneway measurement to "path tree" to cover both onetoone and one
tomany communications. If applied to onetoone communications, the
onetogroup metrics provide exactly the same results as the
corresponding onetoone metrics.
3.3. Discussion on Grouptoone and Grouptogroup metrics
We note that points of interest can also be selected to define
 measurements on Grouptoone and Grouptogroup topologies. These
+ measurements on grouptoone and grouptogroup topologies. These
topologies are currently beyond the scope of this memo, because they
would involve multiple packets launched from different sources.
However, we can give some clues here on these two cases.
The measurements for grouptoone topology can be easily derived from
the onetogroup measurement. The measurement point is the reference
point that is acting as a receiver while all of clients/receivers
defined for onetogroup measurement act as sources in this case.
For the grouptogroup connection topology, it is difficult to define
@@ 472,257 +479,257 @@
Spatial vectors metrics are based on the decomposition of standard
endtoend metrics defined by the IPPM WG in [RFC2679], [RFC2680],
[RFC3393] and [RFC3432].
Definitions are coupled with the corresponding endtoend metrics.
Methodology specificities are common to all the vectors defined and
are consequently discussed in a common section.
4.1. A Definition for Spatial Oneway Delay Vector
 This section is coupled with the definition of TypePOnewayDelay.
 When a parameter from section 3 of [RFC2679] is first used in this
 section, it will be tagged with a trailing asterisk.
+ This section is coupled with the definition of TypePOnewayDelay
+ of the section 3 of [RFC2679]. When a parameter of this definitionis
+ first used in this section, it will be tagged with a trailing
+ asterisk.
Sections 3.5 to 3.8 of [RFC2679] give requirements and applicability
statements for endtoend onewaydelay measurements. They are
applicable to each point of interest Hi involved in the measure.
Spatial onewaydelay measurement SHOULD be respectful of them,
especially those related to methodology, clock, uncertainties and
reporting.
 Following we adapt some of them and introduce points specific to
 spatial measurement.

4.1.1. Metric Name
TypePSpatialOnewayDelayVector
4.1.2. Metric Parameters
o Src*, the IP address of the sender.
o Dst*, the IP address of the receiver.
 o i, An integer if the list <1,2,...,n> which ordered the hosts in
 the path.
+ o i, An integer in the ordered list <1,2,...,n> of hosts in the
+ path.
o Hi, A host* of the path digest.
o T*, a time, the sending (or initial observation) time for a
measured packet.
 o dT* a delay, the oneway delay for a measured packet.
+ o dT*, a delay, the oneway delay for a measured packet.
o a list of delay.
o P*, the specification of the packet type.
o , hosts path digest.
4.1.3. Metric Units
 A sequence of times.
+ The value of TypePSpatialOnewayDelayVector is a sequence of
+ times.
4.1.4. Definition
Given a TypeP packet sent by the sender Src at wiretime (first bit)
T to the receiver Dst in the path . Given the
sequence of values such that dT is the
TypePOnewayDelay from Src to Dst and such that for each Hi of the
path, T+dTi is either a real number corresponding to the wiretime
the packet passes (last bit received) Hi, or undefined if the packet
never passes Hi.
TypePSpatialOnewayDelayVector metric is defined for the path
as the sequence of values
.
4.1.5. Discussion
Following are specific issues which may occur:
 o the delay looks to decrease: dTi > DTi+1. This seem typically du
 to some clock synchronisation issue. This point is discussed in
 the section 3.7.1. "Errors or uncertainties related to Clocks" of
 of [RFC2679]. One consequence of these uncertainties is that
 times of a measure at different hosts shall not be used to order
 hosts on the path of a measure;
+ o the delay looks to decrease: dTi > DTi+1. This may occur despite
+ it does not make sense per definition:
 o The location of the point of interest in the device influences the
 result. If the packet is not observed on the input interface the
 delay includes buffering time and consequently an uncertainty due
 to the difference between 'wire time' and 'host time';
+ * This is frequently due to some clock synchronization issue.
+ This point is discussed in the section 3.7.1. "Errors or
+ uncertainties related to Clocks" of [RFC2679]. Consequently,
+ times of a measure at different hosts do not guaranty the
+ ordering of the hosts on the path of a measure.
+
+ * During some change of routes the order of 2 hosts may change on
+ the main path;
+
+ * The location of the point of interest in the device influences
+ the result. If the packet is not observed directly on the
+ input interface the delay includes buffering time and
+ consequently an uncertainty due to the difference between 'wire
+ time' and 'host time'
4.2. A Definition for Spatial Oneway Packet Loss Vector
This section is coupled with the definition of TypePOnewayPacket
Loss. Then when a parameter from the section 2 of [RFC2680] is first
used in this section, it will be tagged with a trailing asterisk.
Sections 2.5 to 2.8 of [RFC2680] give requirements and applicability
 statements for endtoend onewayPacketLoss measurements. They are
+ statements for endtoend oneway packet loss measurements. They are
applicable to each point of interest Hi involved in the measure.
Spatial packet loss measurement SHOULD be respectful of them,
especially those related to methodology, clock, uncertainties and
reporting.
Following we define the spatial metric, then we adapt some of the
points above and introduce points specific to spatial measurement.
4.2.1. Metric Name
TypePSpatialOnewayPacketLossVector
4.2.2. Metric Parameters
 + Src*, the IP address of the sender.
+ o Src*, the IP address of the sender.
 + Dst*, the IP address of the receiver.
+ o Dst*, the IP address of the receiver.
 + i, An integer which ordered the hosts in the path.
+ o i, an integer which ordered the hosts in the path.
 + Hi, exchange points of the path digest.
+ o Hi, points of interests of the path digest.
 + T*, a time, the sending (or initial observation) time for
 a measured packet.
+ o T*, a time, the sending time for a measured packet.
 + dT1,..., dTn, dT, a list of delay.
+ o , a list of delay.
 + P*, the specification of the packet type.
+ o P*, the specification of the packet type.
 + , hosts path digest.
+ o , hosts path digest.
 + B1, B2, ..., Bi, ..., Bn, a list of Boolean values.
+ o , a list of Boolean values.
4.2.3. Metric Units
 A sequence of Boolean values.
+ The value of TypePSpatialOnewayPacketLossVector is a sequence
+ of Boolean values.
4.2.4. Definition
Given a TypeP packet sent by the sender Src at time T to the
receiver Dst in the path . Given the sequence of
 times the packet passes ,

 TypePOnewayPacketLostVector metric is defined as the sequence
 of values such that for each Hi of the path, a
 value of Bi of 0 means that dTi is a finite value, and a value of 1
 means that dTi is undefined.
+ times the packet passes in ,
+ we define TypePOnewayPacketLostVector metric as the sequence of
+ values such that for each Hi of the path, a value
+ of 0 for Li means that dTi is a finite value, and a value of 1 means
+ that dTi is undefined.
4.2.5. Discussion
Following are specific issues which may occur:
 o the result includes the sequence 1,0. This case means that the
 packet was seen by a host but not by it successor on the path;
+ o The result includes the sequence 1,0. This may occur under
+ specific situations:
 The location of the point of interest in the device influences the
 result:
+ * During some change of routes a packet may be seen by a host but
+ not by it successor on the main path;
 o Even if the packet is received by a host, it may be not observed
 by the point of interest located after a buffer;
+ * A packet may not be observed in a host due to some buffer or
+ CPU overflow in the point of interest;
4.3. A Definition for Spatial Oneway Ipdv Vector
This section uses parameters from the definition of TypePOneway
ipdv. When a parameter from section 2 of [RFC3393] is first used in
this section, it will be tagged with a trailing asterisk.
 Following we adapt some of them and introduce points specific which
 are to spatial measurement.
+ In the following we adapt some of them and introduce points specific
+ to spatial measurement.
4.3.1. Metric Name
TypePSpatialOnewayipdvVector
4.3.2. Metric Parameters
 + Src*, the IP address of the sender.
+ o Src*, the IP address of the sender.
 + Dst*, the IP address of the receiver.
+ o Dst*, the IP address of the receiver.
 + i, An integer which ordered the hosts in the path.
+ o i, An integer in the ordered list <1,2,...,n> of hosts in the
+ path.
 + Hi, exchange points of the path digest.
+ o Hi, A host* of the path digest.
 + T1*, the time the first packet was sent.
+ o T1*, a time, the sending time for a first measured packet.
 + T2*, the time the second packet was sent.
+ o T2*, a time, the sending time for a second measured packet.
 + P, the specification of the packet type.
+ o dT*, a delay, the oneway delay for a measured packet.
 + P1, the first packet sent at time T1.
+ o P*, the specification of the packets type.
 + P2, the second packet sent at time T2.
+ o P1, the first packet sent at time T1.
 + , host path digest.
+ o P2, the second packet sent at time T2.
 + ,
 the TypePSpatialOnewayDelayVector for packet sent at
 time T1;
+ o , hosts path digest.
 + ,
 the TypePSpatialOnewayDelayVector for packet sent at
 time T2;
+ o , the TypePSpatialOneway
+ DelayVector for packet sent at time T1.
 + L*, a packet length in bits. The packets of a Type P
 packet stream from which the
 TypePSpatialOnewayDelayVector metric is taken MUST
 all be of the same length.
+ o , the TypePSpatialOneway
+ DelayVector for packet sent at time T2.
+
+ o L*, a packet length in bits. The packets of a Type P packet
+ stream from which the TypePSpatialOnewayDelayVector metric
+ is taken MUST all be of the same length.
4.3.3. Metric Units
 A sequence of times.
+ The value of TypePSpatialOnewayipdvVector is a sequence of
+ times.
4.3.4. Definition
 Given the TypeP packet having the size L and sent by the sender Src
 at wiretime (first bit) T1 to the receiver Dst in the path .

 Given the TypeP packet having the size L and sent by the sender Src
 at wiretime (first bit) T2 to the receiver Dst in the same path.

 Given the TypePSpatialOnewayDelayVector of the packet P1.
+ Given P1 the TypeP packet sent by the sender Src at wiretime (first
+ bit) T1 to the receiver Dst and
+ its TypePSpatialOnewayDelayVector over the path .
 Given the TypePSpatialOnewayDelayVector of the packet P2.
+ Given P2 the TypeP packet sent by the sender Src at wiretime (first
+ bit) T2 to the receiver Dst and
+ its TypePSpatialOnewayDelayVector over the same path.
TypePSpatialOnewayipdvVector metric is defined as the sequence
 of values
 Such that for each Hi of the path , dT2.idT1.i is
 either a real number if the packets P1 and P2 passes Hi at wiretime
 (last bit) dT1.i, respectively dT2.i, or undefined if at least one of
 them never passes Hi. T2T1 is the interpacket emission interval
 and dT2dT1 is ddT* the TypePOnewayipdv at T1,T2*.
+ of values such that for each Hi of the path , dT2.idT1.i
+ is either a real number if the packets P1 and P2 passe Hi at wire
+ time (last bit) dT1.i, respectively dT2.i, or undefined if at least
+ one of them never passes Hi. T2T1 is the interpacket emission
+ interval and dT2dT1 is ddT* the TypePOnewayipdv at T1,T2*.
4.4. Spatial Methodology
Methodology, reporting and uncertainties points specified in section
 3 of [RFC2679][RFC2679] applies to each point of interest Hi
 measuring a element of a spatial delay vector.
+ 3 of [RFC2679] applies to each point of interest Hi measuring a
+ element of a spatial delay vector.
Methodology, reporting and uncertainties points specified in section
 2 of [RFC2680][RFC2680] applies to each point of interest Hi
 measuring a element of a spatial packet loss vector.
+ 2 of [RFC2680] applies to each point of interest Hi measuring a
+ element of a spatial packet loss vector.
Sections 3.5 to 3.7 of [RFC3393] give requirements and applicability
statements for endtoend Oneway ipdv measurements. They are
applicable to each point of interest Hi involved in the measure.
Spatial Oneway ipdv measurement SHOULD be respectful of methodology,
clock, uncertainties and reporting aspects given in this section.
Generally, for a given TypeP of length L, in a given Hi, the
 methodology for spatial vector metrics would proceed as follows:
+ methodology for spatial vector metrics may proceed as follows:
o At each Hi, points of interest prepare to capture the packet sent
a time T, take a timestamp Ti', determine the internal delay
correction dTi' (See section 3.7.1. "Errors or uncertainties
related to Clocks" of [RFC2679]),
o Each Hi extracts the path ordering information from the packet
(e.g. timetolive);
o Each Hi compute the wiretime from Src to Hi: Ti = Ti'  dTi'.
@@ 723,418 +730,566 @@
related to Clocks" of [RFC2679]),
o Each Hi extracts the path ordering information from the packet
(e.g. timetolive);
o Each Hi compute the wiretime from Src to Hi: Ti = Ti'  dTi'.
This arrival time is undefined (infinite) if the packet is not
detected after the 'loss threshold' duration;
o Each Hi extracts the timestamp T from the packet;
+
o Each Hi computes the onewaydelay from Src to Hi: dTi = Ti  T;
 o The reference point gathers the result and timetolive of each Hi
 and order them according to the path to build the TypePSpatial
 OnewayDelayVector metric over the path
 .
+ o The reference point gathers the result of each Hi and order them
+ according to the path ordering information received to build the
+ typeP spatial oneway vector (e.g. TypePSpatialOnewayDelay
+ Vector metric ) over the path at time T.
4.4.1. Loss threshold
Loss threshold is the centrality of any methodology because it
determines the presence the packet in the measurement process of the
point of interest and consequently determines any ground truth metric
result. It determines the presence of an effective delay, and bias
the measure of ipdv, of packet loss and of the statistics.
This is consistent for endtoend but impacts spatial measure:
 depending on the consistency of the Loss threshold among the points
+ depending on the consistency of the loss threshold among the points
of interest, a packet may be considered loss a one host but present
in another one, or may be observed by the last host (last hop) of the
path but considered lost by Dst. The analysis of such results is not
 deterministic: has the path change? Does the packet arrive at
+ deterministic: Has the path change? Does the packet arrive at
destination or was it lost during the last mile? The same applies,
of course, for onewaydelay measures: a delay measured may be
infinite at one host but a real value in another one, or may be
measured as a real value by the last host of the path but observed as
 infinite by Dst. The Loss threshold should be set up with the same
 value in each host of the path and in the destination. The Loss
+ infinite by Dst. The loss threshold should be set up with the same
+ value in each host of the path and in the destination. The loss
threshold must be systematically reported to permit careful
introspection and to avoid the introduction of any contradiction in
the statistic computation process.
4.4.2. Host Path Digest
 The methodology given above adds the order of the points of interest
 over the path to [RFC2679] one's.

 A perfect Host Path Digest (hum! of cource from the measurement point
 of view only, that is, corresponding to the real path the test packet
 experimented) may include several times several hosts:
+ The methodology given above relies on the order of the points of
+ interest over the path to [RFC2679] one's.
 o coresponds to a loop in the path;
+ A test packets may cross several times the same host resulting in the
+ repetition of one or several hosts in the Path Digest.
 o coresponds to a loop in the path which
 may occurs during rerouting phases;
+ As an example. This occurs typically during rerouting phases which
+ introduce temporary micro loops. During such an event the host path
+ digest for a packet crossing Ha and Hb may include the pattern meaning that Ha ended the computation of the new path
+ before Hb and that the initial path wath from Ha to Hb and that the
+ new path is from Hb to Ha.
 These cases MUST be identified before statistics computation to avoid
 corrupted results' production. This applies especially to the
 measure of segments which are build from results of a measure of a
 vector metric.
+ Consequently, duplication of hosts in the Path Digest of a vectors
+ MUST be identified before statistics computation to avoid corrupted
+ results' production.
5. Spatial Segments metrics definitions
 This section defines samples to measure a sequence of delays, a
 sequence of lost and a sequence of ipdv between 2 hosts of the path,
 a segment. Singletons are taken from segments of vectors defined
 above.
+ This section defines samples to measure the performance of a segment
+ of a path over time. Definitions rely on matrix of the spatial
+ vector metrics defined above.
+
+ Firstly it defines a sample of oneway delay, TypePSegmentOneway
+ DelayStream, and a sample of packet loss, TypePsegmentPacket
+ lossStream.
+
+ Then it defines 2 different samples of ipdv. The first metric, Type
+ PSegmentOnewayipdvprevStream, uses the previous packet as the
+ selection function. The second metric, TypePSegmentOnewayipdv
+ minStream, uses the minimum delay as the selection.
5.1. A Definition of a sample of Oneway Delay of a segment of the path
 This metric defines a sample of Oneway delays between a pair of
 hosts of a path.
+ This metric defines a sample of Oneway delays over time between a
+ pair of hosts of a path.
+
+ As its semantic is very close to the metric TypePPacketlossStream
+ defined in section 4 of [RFC2679], sections 4.5 to 4.8 of [RFC2679]
+ are part of the current definition.
5.1.1. Metric Name
TypePSegmentOnewayDelayStream
5.1.2. Metric Parameters
 + Src*, the IP address of the sender.
+ o Src*, the IP address of the sender.
 + Dst*, the IP address of the receiver.
+ o Dst*, the IP address of the receiver.
 + P*, the specification of the packet type;
+ o P*, the specification of the packet type.
 + i, An integer which orders exchange points in the path.
+ o i, an integer in the ordered list <1,2,...,n> of hosts in the
+ path.
 + k, An integer which orders the packets sent.
+ o k, an integer which orders the packets sent.
 + Hi, a host of the path digest;
+ o a and b, 2 integers where b > a.
 + , host path digest.
+ o Hi, a host* of the path digest.
 + Ha, a host of the path digest different from Dst and Hb;
+ o , hosts path digest.
 + Hb, a host of the path digest different from Src and Ha.
 Hb order in the path must greater that Ha;
+ o , a list of times.
 + , a list of time ordered by k;
+5.1.3. Metric Units
 + dT1,..., dTn a list of delay;
+ The value of a TypePSegmentOnewayDelayStream is a pair of
5.1.3. Metric Units
+ list of times ;
 A sequence of delay
+ sequence of delays.
5.1.4. Definition
 Given 2 hosts Ha and Hb of the path , given
 a flow of packets of TypeP sent from Src to Dst at the times T1,
 T2... Tn. At each of these times, we obtain a TypePSpatialOne
 wayDelayVector . We define
 the value of the sample TypePsegmentOnewayDelayStream as the
 sequence made up of the delays dTk.b  dTk.a. dTk.a is the delay
 between Src and Ha. dTk.b is the delay between Src and Hb. 'dTk.b 
 dTk.a' is the oneway delay experienced by the packet sent by Src at
 the time Tk when going from Ha to Hb.
+ Given 2 hosts, Ha and Hb, of the path , given the matrix of TypePSpatialOnewayDelayVector for the
+ packets sent from Src to Dst at times :
5.1.5. Discussion
+ ;
 Following are specific issues which may occur:
+ ;
 o When a is Src is the measure of the first hop.
+ ...
 o When b is Dst is the measure of the last hop.
+ .
+
+ We define the sample TypePsegmentOnewayDelayStream as the
+ sequence such that for
+ each time Tk, 'dTk.ab' is either the real number 'dTk.b  dTk.a' if
+ the packet send a time Tk passes Ha and Hb or undefined if this
+ packet never passes Ha or (inclusive) never passes Hb.
+
+5.1.5. Discussion
+
+ Following are specific issues which may occur:
o the delay looks to decrease: dTi > DTi+1:
 * This is typically du to clock synchronisation issue. this point
 is discussed in the section 3.7.1. "Errors or uncertainties
 related to Clocks" of of [RFC2679];
+ * This is typically due to clock synchronization issue. this
+ point is discussed in the section 3.7.1. "Errors or
+ uncertainties related to Clocks" of of [RFC2679];
* This may occurs too when the clock resolution of one probe is
bigger than the minimum delay of a path. As an example this
happen when measuring the delay of a path which is 500 km long
with one probe synchronized using NTP having a clock resolution
of 8ms.
 o The location of the point of interest in the device influences the
 result. If the packet is not observed on the input interface the
 delay includes buffering time and consequently an uncertainty due
 to the difference between 'wire time' and 'host time';
+ The metric can not be performed on < T1 , T2, ..., Tm1, Tm> in the
+ following cases:
 o dTk.b may be observed and not dTk.a.
+ o Ha or Hb disappears from the path due to some change of routes;
+
+ o The order of Ha and Hb changes in the path;
5.2. A Definition of a sample of Packet Loss of a segment of the path
 This metric defines a sample of Packet lost between a pair of hosts
 of a path.
+ This metric defines a sample of packet lost over time between a pair
+ of hosts of a path. As its semantic is very close to the metric
+ TypePPacketlossStream defined in section 3 of [RFC2680], sections
+ 3.5 to 3.8 of [RFC2680] are part of the current definition.
5.2.1. Metric Name
TypePsegmentPacketlossStream
5.2.2. Metric Parameters
 + Src*, the IP address of the sender.

 + Dst*, the IP address of the receiver.
+ o Src*, the IP address of the sender.
 + P*, the specification of the packet type.
+ o Dst*, the IP address of the receiver.
 + k, An integer which orders the packets sent.
+ o P*, the specification of the packet type.
 + n, An integer which orders the hosts on the path.
+ o k, an integer which orders the packets sent.
 + , hosts path digest.
+ o n, an integer which orders the hosts on the path.
 + Ha, a host of the path digest different from Dst and Hb;
+ o a and b, 2 integers where b > a.
 + Hb, a host of the path digest different from Src and Ha.
 Hb order in the path must greater that Ha;
+ o , hosts path digest.
 + Hi, exchange points of the path digest.
+ o Hi, exchange points of the path digest.
 + a list of bits.
+ o , a list of times.
 + a list of integers.
+ o a list of boolean values.
5.2.3. Metric Units
 A sequence of integers
+ The value of a TypePsegmentPacketlossStream is a pair of
+
+ The list of times ;
+
+ a sequence of booleans.
5.2.4. Definition
 Given 2 hosts Ha and Hb of the path , given
 a flow of packets of TypeP sent from Src to Dst at the times T1,
 T2... Tn. At each of these times, we obtain a TypePSpatial
 PacketLostVector . We define the value of
 the sample TypePsegmentPacketLostStream between Ha and Hb as the
 sequence made up of the integer such that for each
 Tk:
+ Given 2 hosts, Ha and Hb, of the path , given the matrix of TypePSpatialPacketlossVector for the
+ packets sent from Src to Dst at times :
 o a value of Lk of 0 means that Bk.a has a value of 0 (observed) and
 that Bk.b have a value of 0 (observed);
 o a value of Lk of 1 means that Bk.a has a value of 0 (observed) and
 that Bk.b have a value of 1 (not observed);
+ ,
 o a value of Lk of 2 means that Bk.a has a value of 1 (not observed)
 and that Bk.b have a value of 0 (observed);
+ ,
 o a value of Lk of 3 means that Bk.a has a value of 1 (not observed)
 and that Bk.b have a value of 1 (not observed).
+ ...,
5.2.5. Discussion
+ .
 The semantic of a TypePsegmentPacketlossStream is similar to the
 one of TypePPacketlossStream:
+ We define the value of the sample TypePsegmentPacketLostStream
+ from Ha to Hb as the sequence of booleans such that for each Tk:
 o a value of 0 means that the packet was observed by Ha (similar to
 'send by Src') and not observed by Hb ( similar to 'not received
 by Dst');
+ o A value of Lk of 0 means that Ha and Hb observed the packet sent
+ at time Tk (Lk.a and Lk.b have a value of 0);
 o a value of 1 means that it was observed by Ha (similar to 'send by
 Src') and observed by Hb ( similar to 'received by Dst').
+ o A value of Lk of 1 means that Ha observed the packet sent at time
+ Tk (Lk.a has a value of 0) and that Hb did not observed the packet
+ sent at time Tk (Lk.b have a value of 1);
+ o The value of Lk is undefined when Neither Ha or Hb observe the
+ packet;
 This definition of TypePsegmentPacketlossStream is similar to
 the TypePPacketlossStream defined in [RFC2680] excepted that in a
 TypePsegmentPacketlossStream the rules of the point of interests
 Ha and Hb are symetrical: The asumption that a set of packets are
 going from Ha to Hb does not apply to TypePsegmentPacketloss
 Stream because as the host path digest is dynamic each packet has its
 own host path digest.
+5.2.5. Discussion
 Making the asumption that the host path digest of a TypePspatial
 Packetlossvector does not change and that the set of (Hk, Hk+1)
 tuples is mostly stable over time lead to unusable results and to the
 introduction of mistakes in the metrics aggregation processes. The
 right approach consists in carefully scrutening the path ordering
 information to build sample with elements of vectors sharing the same
 properties in term of Ha and Hb and 'Ha to Hb'. So a measure of
 TypePspatialPacketlossvector differs from a TypePPacketloss
 one in that it produces different samples of packet loss over time.
+ Unlike TypePPacketlossStream, TypePSegmentPacketlossStream
+ relies on the stability of the host path digest. The metric can not
+ be performed on < T1 , T2, ..., Tm1, Tm> in the following cases:
 The semantic of a TypePsegmentPacketlossStream defines 2 new
 results:
+ o Ha or Hb disappears from the path due to some change of routes;
 o A value of Lk of 2 (1,0) corresponds to a mistake in the ordering
 of Ha and Hb over the path coming either from the configuration
 (asumption on the path) or from the processing of the vectors: bad
 scrutening of the path ordering information, or some other mistake
 in the measure or the reporting. It is not in the scope of this
 document to go in further details which are mostly implementation
 dependent. This value MUST not be used to compute packet lost
 statistics.
+ o the order of Ha and Hb changes in the path;
 o A value of Lk of 3 (1,1) corresponds to a lost of the packet in
 upper segment of the path.
+ o Lk.a or Lk.b is undefined;
5.3. A Definition of a sample of Oneway Ipdv of a segment of the path
+ o Lk.a has the value 1 (not observed) and Lk.b has the value 0
+ (observed);
 This metric defines a sample of ipdv between a pair of hosts of a
 path.
+ o L has the value 0 (the packet was received by Dst) and Lk.ab has
+ the value 1 (the packet was lost between Ha and Hb).
 Editor note: work in progress
+5.3. A Definition of a sample of ipdv of a segment using the previous
+ packet selection function
+
+ This metric defines a sample of ipdv [RFC3393] over time between a
+ pair of hosts using the previous packet as the selection function.
5.3.1. Metric Name
 TypePSegmentIpdvStream
+ TypePSegmentOnewayipdvprevStream
5.3.2. Metric Parameters
+ o Src*, the IP address of the sender.
+
+ o Dst*, the IP address of the receiver.
+
+ o P*, the specification of the packet type.
+
+ o k, an integer which orders the packets sent.
+
+ o n, an integer which orders the hosts on the path.
+
+ o a and b, 2 integers where b > a.
+
+ o , the hosts path digest.
+
+ o , a list of times.
+
+ o , a
+ TypePSpatialOnewayDelayVector.
+
5.3.3. Metric Units
+ The value of a TypePSegmentOnewayipdvprevStream is a pair of:
+
+ The list of ;
+
+ A list of pairs of interval of times and delays;
+
5.3.4. Definition
+ Given 2 hosts, Ha and Hb, of the path , given the matrix of TypePSpatialOnewayDelayVector for the
+ packets sent from Src to Dst at times :
+
+ ,
+
+ ,
+
+ ...
+
+ .
+
+ We define the TypePSegmentOnewayipdvprevStream as the sequence
+ of pair of packet intervals and delay variations <(dT2_1.a , dT2.ab 
+ dT1.ab) ,..., (dTk_k1.a, dTk.ab  dTk1.ab), ..., (dTm_m1.a, dTm.ab
+  dTm1.ab)> such that for each Tk:
+
+ o dTk_k1.a is either undefined if the delay dTk.a or the delay
+ dTk1.a is undefined, or the interval of time, 'dTk.a  dTk1.a',
+ between the 2 packets at Ha;
+
+ o dTk_k1.ab, is either undefined if one of the delays dTk.b, dTk.a,
+ dTk1.b or dTk1.a is undefined, or , (dTk.b  dTk.a)  (dTk1.b 
+ dTk1.a), the delay variation from Ha to Hb between the 2 packets
+ sent at time Tk and Tk1.
+
5.3.5. Discussion
+ This metric belongs to the family of inter packet delay variation
+ metrics (IPDV in upper case) which results can be extremely sensitive
+ to the interpacket interval.
+
+ The interpacket interval of a endtoend IPDV metric is under the
+ control of the ingress point of interest which corresponds exactly to
+ the Source of the packet. Unlikely, the interpacket interval of a
+ segment IPDV metric is not under the control the ingress point of
+ interest of the measure, Ha. However, the interval will vary if
+ there is delay variation between the Source and Ha. Therefore, the
+ actual interpacket interval must be known at Ha in order to fully
+ comprehend the delay variation between Ha and Hb.
+
+5.4. A Definition of a sample of ipdv of a segment using the minimum
+ delay selection function
+
+ This metric defines a sample of ipdv [RFC3393] over time between a
+ pair of hosts of a path using the shortest delay as the selection
+ function.
+
+5.4.1. Metric Name
+
+ TypePSegmentOnewayipdvminStream
+
+5.4.2. Metric Parameters
+
+ o Src*, the IP address of the sender.
+
+ o Dst*, the IP address of the receiver.
+
+ o P*, the specification of the packet type.
+
+ o k, an integer which orders the packets sent.
+
+ o i, an integer which identifies a packet sent.
+
+ o n, an integer which orders the hosts on the path.
+
+ o a and b, 2 integers where b > a.
+
+ o , the hosts path digest.
+
+ o , a list of times.
+
+ o , a
+ TypePSpatialOnewayDelayVector.
+
+5.4.3. Metric Units
+
+ The value of a TypePSegmentOnewayipdvminStream is a pair of:
+
+ The list of ;
+ A list of times;
+
+5.4.4. Definition
+
+ Given 2 hosts, Ha and Hb, of the path , given the matrix of TypePSpatialOnewayDelayVector for the
+ packets sent from Src to Dst at times :
+
+ ,
+
+ ,
+
+ ...
+
+ .
+
+ We define the TypePSegmentOnewayipdvminStream as the sequence
+ of times such that:
+
+ min(dTi.ab) is the minimum value of the tuples (dTk.b  dTk.a);
+
+ for each time Tk, dTk.ab is undefined if dTk.a or (inclusive)
+ dTk.b is undefined, or the real number (dTk.b  dTk.a).
+
+5.4.5. Discussion
+
+ This metric belongs to the family of packet delay variation metrics
+ (PDV). PDV distributions are less sensitive to interpacket interval
+ variations than IPDV results.
+
+ In principle, the PDV distribution reflects the variation over many
+ different interpacket intervals, from the smallest interpacket
+ interval, up to the length of the evaluation interval, Tm  T1.
+ Therefore, when delay variation occurs and disturbs the packet
+ spacing observed at Ha, the PDV results will likely compare favorably
+ to a PDV measurement where the source is Ha and the destination is
+ Hb.
+
6. Onetogroup metrics definitions
6.1. A Definition for onetogroup Oneway Delay
+ This metric defines metrics to measure the performance between a
+ source and a group of receivers.
+
+6.1. A Definition for Onetogroup Oneway Delay
+
+ This metric defines a metric to measure oneway delay between a
+ source and a group of receivers.
6.1.1. Metric Name
 TypePonetogroupOnewayDelayVector
+ TypePOnetogroupOnewayDelayVector
6.1.2. Metric Parameters
o Src, the IP address of a host acting as the source.
o Recv1,..., RecvN, the IP addresses of the N hosts acting as
receivers.
o T, a time.
o dT1,...,dTn a list of time.
o P, the specification of the packet type.
 o Gr, the multicast group address (optional). The parameter Gr is
 the multicast group address if the measured packets are
 transmitted by multicast. This parameter is to identify the
+ o Gr, the receiving group identifier. The parameter Gr is the
+ multicast group address if the measured packets are transmitted
+ over IP multicast. This parameter is to differentiate the
measured traffic from other unicast and multicast traffic. It is
 set to be optional in the metric to avoid losing any generality,
 i.e. to make the metric also applicable to unicast measurement
 where there is only one receivers.
+ optional in the metric to avoid losing any generality, i.e. to
+ make the metric also applicable to unicast measurement where there
+ is only one receiver.
6.1.3. Metric Units
 The value of a TypePonetogroupOnewayDelayVector is a set of
 singletons metrics TypePOnewayDelay [RFC2679].
+ The value of a TypePOnetogroupOnewayDelayVector is a set of
+ TypePOnewayDelay singletons [RFC2679].
6.1.4. Definition
Given a Type P packet sent by the source Src at Time T, given the N
hosts { Recv1,...,RecvN } which receive the packet at the time {
 T+dT1,...,T+dTn }, a TypePonetogroupOnewayDelayVector is
+ T+dT1,...,T+dTn }, a TypePOnetogroupOnewayDelayVector is
defined as the set of the TypePOnewayDelay singleton between Src
and each receiver with value of { dT1, dT2,...,dTn }.
6.2. A Definition for onetogroup Oneway Packet Loss
+6.2. A Definition for Onetogroup Oneway Packet Loss
6.2.1. Metric Name
 TypePonetogroupOnewayPacketLossVector
+ TypePOnetogroupOnewayPacketLossVector
6.2.2. Metric Parameters
o Src, the IP address of a host acting as the source.
o Recv1,..., RecvN, the IP addresses of the N hosts acting as
receivers.
o T, a time.
o T1,...,Tn a list of time.
o P, the specification of the packet type.
 o Gr, the multicast group address (optional).
+ o Gr, the receiving group identifier.
6.2.3. Metric Units
 The value of a TypePonetogroupOnewayPacketLossVector is a
 set of singletons metrics TypePOnewayPacketLoss [RFC2680].
+ The value of a TypePOnetogroupOnewayPacketLossVector is a
+ set of TypePOnewayPacketLoss singletons [RFC2680].
6.2.4. Definition
Given a Type P packet sent by the source Src at T and the N hosts,
Recv1,...,RecvN, which should receive the packet at T1,...,Tn, a
 TypePonetogroupOnewayPacketLossVector is defined as a set of
+ TypePOnetogroupOnewayPacketLossVector is defined as a set of
the TypePOnewayPacketLoss singleton between Src and each of the
receivers {,,..., }.
6.3. A Definition for onetogroup Oneway Ipdv
+6.3. A Definition for Onetogroup Oneway Ipdv
6.3.1. Metric Name
TypePOnetogroupOnewayipdvVector
6.3.2. Metric Parameters
 + Src, the IP address of a host acting as the source.
+ o Src, the IP address of a host acting as the source.
 + Recv1,..., RecvN, the IP addresses of the N hosts acting as
+ o Recv1,..., RecvN, the IP addresses of the N hosts acting as
receivers.
 + T1, a time.
+ o T1, a time.
 + T2, a time.
+ o T2, a time.
 + ddT1,...,ddTn, a list of time.
+ o ddT1, ...,ddTn, a list of time.
 + P, the specification of the packet type.
+ o P, the specification of the packet type.
 + F, a selection function defining unambiguously the two
 packets from the stream selected for the metric.
+ o F, a selection function defining unambiguously the two packets
+ from the stream selected for the metric.
 + Gr, the multicast group address (optional)
+ o Gr, the receiving group identifier.
6.3.3. Metric Units
The value of a TypePOnetogroupOnewayipdvVector is a set of
 singletons metrics TypePOnewayipdv [RFC3393].
+ TypePOnewayipdv singletons [RFC3393].
6.3.4. Definition
 Given a Type P packet stream, TypePonetogroupOnewayipdvVector
+ Given a Type P packet stream, TypePOnetogroupOnewayipdvVector
is defined for two packets from the source Src to the N hosts
{Recv1,...,RecvN },which are selected by the selection function F, as
 the difference between the value of the TypePonetogroupOneway
+ the difference between the value of the TypePOnetogroupOneway
DelayVector from Src to { Recv1,..., RecvN } at time T1 and the
 value of the TypePonetogroup OnewayDelayVector from Src to {
+ value of the TypePOnetogroupOnewayDelayVector from Src to {
Recv1,...,RecvN } at time T2. T1 is the wiretime at which Src sent
the first bit of the first packet, and T2 is the wiretime at which
Src sent the first bit of the second packet. This metric is derived
 from the TypePoneto groupOnewayDelayVector metric.
+ from the TypePOnetogroupOnewayDelayVector metric.
 Therefore, for a set of real number {ddT1,...,ddTn},TypePone to
+ Therefore, for a set of real number {ddT1,...,ddTn},TypePOneto
groupOnewayipdvVector from Src to { Recv1,...,RecvN } at T1, T2
is {ddT1,...,ddTn} means that Src sent two packets, the first at
wiretime T1 (first bit), and the second at wiretime T2 (first bit)
and the packets were received by { Recv1,...,RecvN } at wiretime
{dT1+T1,...,dTn+T1}(last bit of the first packet), and at wiretime
{dT'1+T2,...,dT'n+T2} (last bit of the second packet), and that
{dT'1dT1,...,dT'ndTn} ={ddT1,...,ddTn}.
7. OnetoGroup Sample Statistics
The defined onetogroup metrics above can all be directly achieved
 from the relevant unicast oneway metrics. They managed to collect
 all unicast measurement results of oneway metrics together in one
 profile and sort them by receivers and packets in a multicast group.
 They can provide sufficient information regarding the network
 performance in terms of each receiver and guide engineers to identify
 potential problem happened on each branch of a multicast routing
 tree. However, these metrics can not be directly used to
 conveniently present the performance in terms of a group and neither
 to identify the relative performance situation.
+ from the relevant unicast oneway metrics. They collect all unicast
+ measurement results of oneway metrics together in one profile and
+ sort them by receivers and packets in a receiving group. They
+ provide sufficient information regarding the network performance in
+ terms of each receiver and guide engineers to identify potential
+ problem happened on each branch of a multicast routing tree.
+
+ However, these metrics cannot be directly used to conveniently
+ present the performance in terms of a group and neither to identify
+ the relative performance situation.
From the performance point of view, the multiparty communication
services not only require the absolute performance support but also
the relative performance. The relative performance means the
difference between absolute performance of all users. Directly using
the oneway metrics cannot present the relative performance
situation. However, if we use the variations of all users oneway
parameters, we can have new metrics to measure the difference of the
absolute performance and hence provide the threshold value of
relative performance that a multiparty service might demand. A very
@@ 1152,63 +1307,63 @@
and report the group performance and relative performance to save the
report transmission bandwidth. Statistics have been defined for One
way metrics in corresponding RFCs. They provide the foundation of
definition for performance statistics. For instance, there are
definitions for minimum and maximum Oneway delay in [RFC2679].
However, there is a dramatic difference between the statistics for
onetoone communications and for onetomany communications. The
former one only has statistics over the time dimension while the
later one can have statistics over both time and space dimensions.
This space dimension is introduced by the Matrix concept as
 illustrated in Figure 9. For a Matrix M each row is a set of Oneway
+ illustrated in Figure 4. For a Matrix M each row is a set of Oneway
singletons spreading over the time dimension and each column is
another set of Oneway singletons spreading over the space dimension.
Receivers
Space
^
1  / R1dT1 R1dT2 R1dT3 ... R3dTk \
  
2   R2dT1 R2dT2 R2dT3 ... R3dTk 
  
3   R3dT1 R3dT2 R3dT3 ... R3dTk 
.   
.   
.   
n  \ RndT1 RndT2 RndT3 ... RndTk /
+> time
T0
 Figure 9: Matrix M (n*m)
+ Figure 4: Matrix M (n*m)
 In Matrix M, each element is a Oneway delay singleton. Each column
+ In Matrix M, each element is a oneway delay singleton. Each column
is a delay vector contains the Oneway delays of the same packet
observed at M points of interest. It implies the geographical factor
of the performance within a group. Each row is a set of Oneway
delays observed during a sampling interval at one of the points of
interest. It presents the delay performance at a receiver over the
time dimension.
Therefore, one can either calculate statistics by rows over the space
dimension or by columns over the time dimension. It's up to the
operators or service provides which dimension they are interested in.
For example, a TV broadcast service provider might want to know the
statistical performance of each user in a long term run to make sure
their services are acceptable and stable. While for an online gaming
service provider, he might be more interested to know if all users
are served fairly by calculating the statistics over the space
dimension. This memo does not intend to recommend which of the
statistics are better than the other.
To save the report transmission bandwidth, each point of interest can
send statistics in a predefined time interval to the reference point
 rather than sending every Oneway singleton it observed. As long as
+ rather than sending every oneway singleton it observed. As long as
an appropriate time interval is decided, appropriate statistics can
represent the performance in a certain accurate scale. How to decide
the time interval and how to bootstrap all points of interest and the
reference point depend on applications. For instance, applications
with lower transmission rate can have the time interval longer and
ones with higher transmission rate can have the time interval
shorter. However, this is out of the scope of this memo.
Moreover, after knowing the statistics over the time dimension, one
might want to know how this statistics distributed over the space
@@ 1286,72 +1441,72 @@
User1 calculates the TypePFiniteOnewayDelayMean R1DM as shown
in Figure. 8 without any packet loss and User2 calculates the R2DM
with N2 packet loss. The R1DM and R2DM should not be treated with
equal weight because R2DM was calculated only based on 2 delay values
in the whole sample interval. One possible solution is to use a
weight factor to mark every statistic value sent by users and use
this factor for further statistic calculation.
7.2. General Metric Parameters
 o Src, the IP address of a host
+ o Src, the IP address of a host;
 o G, the Group IP address
+ o G, the receiving group identifier;
 o N, the number of Receivers (Recv1, Recv2, ... RecvN)
+ o N, the number of Receivers (Recv1, Recv2, ... RecvN);
 o T, a time (start of test interval)
+ o T, a time (start of test interval);
 o Tf, a time (end of test interval)
+ o Tf, a time (end of test interval);
o K, the number of packets sent from the source during the test
 interval

+ interval;
o J[n], the number of packets received at a particular Receiver, n,
 where 1<=n<=N
+ where 1<=n<=N;
 o lambda, a rate in reciprocal seconds (for Poisson Streams)
+ o lambda, a rate in reciprocal seconds (for Poisson Streams);
o incT, the nominal duration of interpacket interval, first bit to
 first bit (for Periodic Streams)
+ first bit (for Periodic Streams);
o T0, a time that MUST be selected at random from the interval [T,
T+I] to start generating packets and taking measurements (for
 Periodic Streams)
+ Periodic Streams);
o TstampSrc, the wire time of the packet as measured at MP(Src) (the
 Source Measurement Point)
+ Source Measurement Point);
o TstampRecv, the wire time of the packet as measured at MP(Recv),
 assigned to packets that arrive within a "reasonable" time
+ assigned to packets that arrive within a "reasonable" time;
o Tmax, a maximum waiting time for packets at the destination, set
sufficiently long to disambiguate packets with long delays from
packets that are discarded (lost), thus the distribution of delay
 is not truncated
+ is not truncated;
 o dT, shorthand notation for a oneway delay singleton value
+ o dT, shorthand notation for a oneway delay singleton value;
o L, shorthand notation for a oneway loss singleton value, either
zero or one, where L=1 indicates loss and L=0 indicates arrival at
the destination within TstampSrc + Tmax, may be indexed over n
 Receivers
+ Receivers;
o DV, shorthand notation for a oneway delay variation singleton
 value
+ value;
7.3. OnetoGroup oneway Delay Statistics
This section defines the overall oneway delay statistics for an
entire Group or receivers. For example, we can define the group mean
delay, as illustrated below. This is a metric designed to summarize
the whole matrix.
+
Recv / Sample \ Stats Group Stat
1 R1dT1 R1dT2 R1dT3 ... R1dTk R1DM \

2 R2dT1 R2dT2 R2dT3 ... R2dTk R2DM 

3 R3dT1 R3dT2 R3dT3 ... R3dTk R2DM > GMD
. 
. 
. 
@@ 1350,21 +1505,21 @@
1 R1dT1 R1dT2 R1dT3 ... R1dTk R1DM \

2 R2dT1 R2dT2 R2dT3 ... R2dTk R2DM 

3 R3dT1 R3dT2 R3dT3 ... R3dTk R2DM > GMD
. 
. 
. 
n RndT1 RndT2 RndT3 ... RndTk RnDM /
 Figure 10: OnetoGroupGroup Mean Delay
+ Figure 5: OnetoGroup Mean Delay
where:
R1dT1 is the TypePFiniteOnewayDelay singleton evaluated at
Receiver 1 for packet 1.
R1DM is the TypePFiniteOnewayDelayMean evaluated at Receiver 1
for the sample of packets (1,...K).
GMD is the mean of the sample means over all Receivers (1, ...N).
@@ 1394,39 +1549,39 @@
TypePFiniteOnewayDelayMeanReceivern = RnDM =
J[n]

1 \
 * > TypePFiniteOnewayDelayReceivern[i]
J[n] /

i = 1
 Figure 11: TypePFiniteOnewayDelayMeanReceivern
+ Figure 6: TypePFiniteOnewayDelayMeanReceivern
where all packets i= 1 through J[n] have finite singleton delays.
7.3.3. OnetoGroup Mean Delay Statistic
This section defines the Mean Oneway Delay calculated over the
entire Group (or Matrix).
TypePOnetoGroupMeanDelay = GMD =
N

1 \
 * > RnDM
N /

n = 1
 Figure 12: TypePOnetoGroupMeanDelay
+ Figure 7: TypePOnetoGroupMeanDelay
Note that the Group Mean Delay can also be calculated by summing the
Finite oneway Delay singletons in the Matrix, and dividing by the
number of Finite Oneway Delay singletons.
7.3.4. OnetoGroup Range of Mean Delays
This section defines a metric for the range of mean delays over all N
receivers in the Group, (R1DM, R2DM,...RnDM).
@@ 1451,21 +1606,21 @@
1 R1L1 R1L2 R1L3 ... R1Lk R1LR \

2 R2L1 R2L2 R2L3 ... R2Lk R2LR 

3 R3L1 R3L2 R3L3 ... R3Lk R3LR > GLR
. 
. 
. 
n RnL1 RnL2 RnL3 ... RnLk RnLR /
 Figure 13: OnetoGroup Loss Ratio
+ Figure 8: OnetoGroup Loss Ratio
where:
R1L1 is the TypePOnewayLoss singleton (L) evaluated at Receiver 1
for packet 1.
R1LR is the TypePOnewayLossRatio evaluated at Receiver 1 for the
sample of packets (1,...K).
GLR is the loss ratio over all Receivers (1, ..., N).
@@ 1476,21 +1631,21 @@
TypePOnetoGroupLossRatio =
K,N

1 \
=  * > L(k,n)
K*N /

k,n = 1
 Figure 14
+ Figure 9
ALL Loss ratios are expressed in units of packets lost to total
packets sent.
7.4.2. OnetoGroup Loss Ratio Range
Given a Matrix of loss singletons as illustrated above, determine the
TypePOnewayPacketLossAverage for the sample at each receiver,
according to the definitions and method of [RFC2680]. The TypeP
OnewayPacketLossAverage, RnLR for receiver n, and the TypePOne
@@ 1500,21 +1655,21 @@
TypePOnewayLossRatioReceivern = RnLR =
K

1 \
 * > RnLk
K /

k = 1
 Figure 15: TypePOnewayLossRatioReceivern
+ Figure 10: TypePOnewayLossRatioReceivern
The OnetoGroup Loss Ratio Range is defined as
TypePOnetoGroupLossRatioRange = max(RnLR)  min(RnLR)
It is most effective to indicate the range by giving both the max and
minimum loss ratios for the Group, rather than only reporting the
difference between them.
7.4.3. Comparative Loss Ratio
@@ 1536,31 +1691,31 @@
k=1
= 
/ K \
  
 \ 
K  Min  > Ln(k) 
 / 
  
\ k=1 / N
 Figure 16: TypePCompLossRatioReceivern
+ Figure 11: TypePCompLossRatioReceivern
7.5. OnetoGroup oneway Delay Variation Statistics
There are two delay variation (DV) statistics that summarize the
performance over the Group: the maximum DV over all receivers and the
minimum DV over all receivers (where DV is a pointtopoint metric).
For each receiver, the DV is usually expressed as the 110^(3)
quantile of oneway delay minus the minimum oneway delay.
8. Measurement Methods: Scaleability and Reporting
+8. Measurement Methods: Scalability and Reporting
Virtually all the guidance on measurement processes supplied by the
earlier IPPM RFCs (such as [RFC2679] and [RFC2680]) for onetoone
scenarios is applicable here in the spatial and multiparty
measurement scenario. The main difference is that the spatial and
multiparty configurations require multiple measurement points where a
stream of singletons will be collected. The amount of information
requiring storage grows with both the number of metrics and the
number of measurement points, so the scale of the measurement
architecture multiplies the number of singleton results that must be
@@ 1651,21 +1806,21 @@
. 
. 
n RnS1 RnS2 RnS3 ... RnSk /
S1M S2M S3M ... SnM Stats over space
\ /
\/
Stat over space and time
 Figure 17: Impact of space aggregation on multimetrics Stat
+ Figure 12: Impact of space aggregation on multimetrics Stat
2 methods are available to compute statistics on the resulting
matrix:
o metric is computed over time and then over space;
o metric is computed over space and then over time.
They differ only by the order of the time and of the space
aggregation. View as a matrix this order is neutral as does not
impact the result, but the impact on a measurement deployment is
@@ 1701,24 +1856,24 @@
Note: In some specific cases one may need sample of singletons over
space. To address this need it is suggested firstly to limit the
number of test and the number of test packets per seconds. Then
reducing the size of the sample over time to one packet give sample
of singleton over space..
8.3.1. Impact on group stats
2 methods are available to compute group statistics:
 o method1: Figure 10 andFigure 13 illustrate the method chosen: the
+ o method1: Figure 5 andFigure 8 illustrate the method chosen: the
onetoone statistic is computed per interval of time before the
computation of the mean over the group of receivers;
 o method2: Figure 17 presents the second one, metric is computed
+ o method2: Figure 12 presents the second one, metric is computed
over space and then over time.
8.3.2. Impact on spatial stats
2 methods are available to compute spatial statistics:
o method 1: spatial segment metrics and statistics are preferably
computed over time by each points of interest;
o method 2: Vectors metrics are intrinsically instantaneous space
@@ 1822,30 +1977,20 @@
As explained in section 8, the measurement method will have impact on
the analysis of the measurement result. Therefore, it should be
reported.
9.3. Metric identification
IANA assigns each metric defined by the IPPM WG with a unique
identifier as per [RFC4148] in the IANAIPPMMETRICSREGISTRYMIB.
 To avoid misunderstanding and to address specific reporting
 constraints, section [passive_metrics] of this memo gives distinct
 names to passive metrics and Section 13 requests a distinct metric
 identifier for each metrics the memo defines.

 As it is crucial for composition of metrics to know the methodology
 used (e.g. generation method, detection method...), the report of a
 metric result used in composition of metrics MUST always include its
 metric identifier.

9.4. Reporting data model
This section presents the elements of the datamodel and the usage of
the information reported for real network performance analysis. It
is out of the scope of this section to define how the information is
reported.
The data model is build with pieces of information introduced and
explained in oneway delay definitions [RFC2679], in packet loss
definitions [RFC2680] and in IPDV definitions[RFC3393][RFC3432]. It
@@ 2040,173 +2183,194 @@
13. IANA Considerations
Metrics defined in this memo Metrics defined in this memo are
designed to be registered in the IANA IPPM METRICS REGISTRY as
described in initial version of the registry [RFC4148] :
IANA is asked to register the following metrics in the IANAIPPM
METRICSREGISTRYMIB :
 SpatialOnewayDelayVector OBJECTIDENTITY
+ ietfSpatialOneWayDelayVector OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePSpatialOnewayDelayVector"
REFERENCE
"Reference "RFCyyyy, section 4.1."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 SpatialPacketLossVector OBJECTIDENTITY
+ ietfSpatialPacketLossVector OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePSpatialPacketLossVector"
REFERENCE
"Reference "RFCyyyy, section 4.2."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 SpatialOnewayipdvVector OBJECTIDENTITY
+ ietfSpatialOneWayIpdvVector OBJECTIDENTITY
+
STATUS current
DESCRIPTION
"TypePSpatialOnewayipdvVector"
REFERENCE
"Reference "RFCyyyy, section 4.3."

 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 SpatialSegmentOnewayDelayStream OBJECTIDENTITY
+ ietfSpatialSegmentOnewayDelayStream OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePSpatialSegmentOnewayDelayStream"
REFERENCE
"Reference "RFCyyyy, section 5.1."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 SpatialSegmentPacketLossStream OBJECTIDENTITY
+ ietfSpatialSegmentPacketLossStream OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePSpatialSegmentPacketLossStream"
REFERENCE
"Reference "RFCyyyy, section 5.2."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 SpatialSegmentOnewayipdvStream OBJECTIDENTITY
+
+ ietfSpatialSegmentOneWayIpdvPrevStream OBJECTIDENTITY
STATUS current
DESCRIPTION
 "TypePSpatialSegmentipdvStream"

+ "TypePSpatialSegmentipdvprevStream"
REFERENCE
"Reference "RFCyyyy, section 5.3."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
+ ietfSpatialSegmentOneWayIpdvMinStream OBJECTIDENTITY
+
+ STATUS current
+
+ DESCRIPTION
+
+ "TypePSpatialSegmentipdvminStream"
+
+ REFERENCE
+
+ "Reference "RFCyyyy, section 5.4."
+
+  RFC Ed.: replace yyyy with actual RFC number & remove this
+ note
+
+ := { ianaIppmMetrics nn }  IANA assigns nn
+
 Onetogroup metrics
 onetogroupOnewayDelayVector OBJECTIDENTITY
+ ietfOneToGroupOneWayDelayVector OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePonetogroupOnewayDelayVector"
REFERENCE
 "Reference "RFCyyyy, section 5.1."
+ "Reference "RFCyyyy, section 6.1."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 onetogroupOnewayPacketLossVector OBJECTIDENTITY

+ ietfOneToGroupOneWayPktLossVector OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePonetogroupOnewayPacketLossVector"
REFERENCE
 "Reference "RFCyyyy, section 5.2."
+ "Reference "RFCyyyy, section 6.2."
+
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 onetogroupOnewayipdvVector OBJECTIDENTITY
+ ietfOneToGroupOneWayIpdvVector OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePonetogroupOnewayipdvVector"
REFERENCE
 "Reference "RFCyyyy, section 5.3."
+ "Reference "RFCyyyy, section 6.3."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 OnetoGroupMeanDelay OBJECTIDENTITY
+  One to group statistics
+
+ 
+
+ ietfOneToGroupMeanDelay OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePOnetoGroupMeanDelay"
REFERENCE
"Reference "RFCyyyy, section 6.3.3."
@@ 2203,67 +2367,66 @@
STATUS current
DESCRIPTION
"TypePOnetoGroupMeanDelay"
REFERENCE
"Reference "RFCyyyy, section 6.3.3."

 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 OnetoGroupRangeMeanDelay OBJECTIDENTITY
+ ietfOneToGroupRangeMeanDelay OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePOnetoGroupRangeMeanDelay"
+
REFERENCE
"Reference "RFCyyyy, section 6.3.4."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 OnetoGroupMaxMeanDelay OBJECTIDENTITY
+ ietfOneToGroupMaxMeanDelay OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePOnetoGroupMaxMeanDelay"
REFERENCE
"Reference "RFCyyyy, section 6.3.5."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn
 OnetoGroupLossRatio OBJECTIDENTITY
+ ietfOneToGroupLossRatio OBJECTIDENTITY
STATUS current
DESCRIPTION
"TypePOnetoGroupLossRatio"

REFERENCE
"Reference "RFCyyyy, section 6.4.1."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn

@@ 2261,21 +2424,22 @@
"Reference "RFCyyyy, section 6.4.1."
 RFC Ed.: replace yyyy with actual RFC number & remove this
note
:= { ianaIppmMetrics nn }  IANA assigns nn

 OnetoGroupLossRatioRange OBJECTIDENTITY
+ ietfOneToGroupLossRatioRange OBJECTIDENTITY
+
STATUS current
DESCRIPTION
"TypePOnetoGroupLossRatioRange"
REFERENCE
"Reference "RFCyyyy, section 6.4.2."
@@ 2366,21 +2531,21 @@
Al Morton
200 Laurel Ave. South
Middletown, NJ 07748
USA
Phone: +1 732 420 1571
Email: acmorton@att.com
Full Copyright Statement
 Copyright (C) The IETF Trust (2007).
+ Copyright (C) The IETF Trust (2008).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF