Internet Engineering Task Force (IETF) A. Morton
Request for Comments: 7799 AT&T Labs
Category: Informational May 2016
ISSN: 2070-1721
Internet Engineering Task Force (IETF) A. Morton
Request for Comments: 7799 AT&T Labs
Category: Informational May 2016
ISSN: 2070-1721
Active and Passive Metrics and Methods (with Hybrid Types In-Between)
主动和被动度量和方法（中间有混合类型）
Abstract
摘要
This memo provides clear definitions for Active and Passive performance assessment. The construction of Metrics and Methods can be described as either "Active" or "Passive". Some methods may use a subset of both Active and Passive attributes, and we refer to these as "Hybrid Methods". This memo also describes multiple dimensions to help evaluate new methods as they emerge.
本备忘录为主动和被动绩效评估提供了明确的定义。度量和方法的构造可以描述为“主动”或“被动”。有些方法可能使用主动和被动属性的子集，我们称之为“混合方法”。本备忘录还描述了多个维度，以帮助评估新方法的出现。
Status of This Memo
关于下段备忘
This document is not an Internet Standards Track specification; it is published for informational purposes.
本文件不是互联网标准跟踪规范；它是为了提供信息而发布的。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。并非IESG批准的所有文件都适用于任何级别的互联网标准；见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7799.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc7799.
Copyright Notice
版权公告
Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2016 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction ....................................................2
1.1. Requirements Language ......................................3
2. Purpose and Scope ...............................................3
3. Terms and Definitions ...........................................3
3.1. Performance Metric .........................................3
3.2. Method of Measurement ......................................4
3.3. Observation Point ..........................................4
3.4. Active Methods .............................................4
3.5. Active Metric ..............................................5
3.6. Passive Methods ............................................5
3.7. Passive Metric .............................................6
3.8. Hybrid Methods and Metrics .................................6
4. Discussion ......................................................8
4.1. Graphical Representation ...................................8
4.2. Discussion of PDM .........................................10
4.3. Discussion of "Coloring" Method ...........................11
4.4. Brief Discussion of OAM Methods ...........................11
5. Security Considerations ........................................12
6. References .....................................................12
6.1. Normative References ......................................12
6.2. Informative References ....................................13
Acknowledgements ..................................................14
Author's Address ..................................................14
1. Introduction ....................................................2
1.1. Requirements Language ......................................3
2. Purpose and Scope ...............................................3
3. Terms and Definitions ...........................................3
3.1. Performance Metric .........................................3
3.2. Method of Measurement ......................................4
3.3. Observation Point ..........................................4
3.4. Active Methods .............................................4
3.5. Active Metric ..............................................5
3.6. Passive Methods ............................................5
3.7. Passive Metric .............................................6
3.8. Hybrid Methods and Metrics .................................6
4. Discussion ......................................................8
4.1. Graphical Representation ...................................8
4.2. Discussion of PDM .........................................10
4.3. Discussion of "Coloring" Method ...........................11
4.4. Brief Discussion of OAM Methods ...........................11
5. Security Considerations ........................................12
6. References .....................................................12
6.1. Normative References ......................................12
6.2. Informative References ....................................13
Acknowledgements ..................................................14
Author's Address ..................................................14
The adjectives "Active" and "Passive" have been used for many years to distinguish between two different classes of Internet performance assessment. The first Passive and Active Measurement (PAM) Conference was held in 2000, but the earliest proceedings available online are from the second PAM conference in 2001 <https://www.ripe.net/ripe/meetings/pam-2001>.
形容词“主动”和“被动”多年来一直用于区分两种不同的互联网绩效评估。第一次被动和主动测量（PAM）会议于2000年举行，但最早的在线会议记录来自2001年的第二次PAM会议<https://www.ripe.net/ripe/meetings/pam-2001>.
The notions of "Active" and "Passive" are well-established. In general:
“主动”和“被动”的概念早已确立。一般来说：
o An Active Metric or Method depends on a dedicated measurement packet stream and observations of the stream.
o 活动度量或方法取决于专用测量数据包流和流的观测值。
o A Passive Metric or Method depends *solely* on observation of one or more existing packet streams. The streams only serve measurement when they are observed for that purpose, and are present whether or not measurements take place.
o 被动度量或方法*仅*依赖于*对一个或多个现有分组流的观察。流仅在为此目的进行观察时用于测量，并且无论是否进行测量，流都存在。
As new techniques for assessment emerge, it is helpful to have clear definitions of these notions. This memo provides more-detailed definitions, defines a new category for combinations of traditional Active and Passive techniques, and discusses dimensions to evaluate new techniques as they emerge.
随着新的评估技术的出现，对这些概念有明确的定义是很有帮助的。本备忘录提供了更详细的定义，为传统主动和被动技术的组合定义了一个新的类别，并讨论了评估新技术的维度。
This memo provides definitions for Active and Passive Metrics and Methods based on long usage in the Internet measurement community, and especially the Internet Engineering Task Force (IETF). This memo also describes the combination of fundamental Active and Passive categories that are called Hybrid Methods and Metrics.
本备忘录提供了基于互联网测量社区，特别是互联网工程任务组（IETF）长期使用的主动和被动度量和方法的定义。本备忘录还描述了被称为混合方法和度量的基本主动和被动类别的组合。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
The scope of this memo is to define and describe Active and Passive versions of metrics and methods that are consistent with the long-time usage of these adjectives in the Internet measurement community and especially the IETF. Since the science of measurement is expanding, we provide a category for combinations of the traditional extremes, treating Active and Passive as a continuum and designating combinations of their attributes as Hybrid Methods.
本备忘录的范围是定义和描述主动和被动版本的度量和方法，这些度量和方法与互联网度量社区，特别是IETF中这些形容词的长期使用相一致。由于测量科学的发展，我们为传统极端的组合提供了一个类别，将主动和被动视为一个连续统一体，并将其属性组合指定为混合方法。
Further, this memo's purpose includes describing multiple dimensions to evaluate new methods as they emerge.
此外，本备忘录的目的包括描述多个维度，以便在新方法出现时对其进行评估。
This section defines the key terms of the memo. Some definitions use the notion of "stream of interest", which is synonymous with "population of interest" defined in clause 6.1.1 of ITU-T Recommendation Y.1540 [Y.1540]. These definitions will be useful for any work in progress, such as [PASSIVE] (with which there is already good consistency).
本节定义了备忘录的关键术语。一些定义使用了“利益流”的概念，它与ITU-T建议Y.1540[Y.1540]第6.1.1条中定义的“利益群体”同义。这些定义对于任何正在进行的工作都很有用，例如[被动]（与之已经有很好的一致性）。
The standard definition of a quantity, produced in an assessment of performance and/or reliability of the network, which has an intended utility and is carefully specified to convey the exact meaning of a measured value. (This definition is consistent with that of Performance Metric in [RFC2330] and [RFC6390]).
在对网络性能和/或可靠性进行评估时产生的数量的标准定义，该数量具有预期用途，并被仔细指定以传达测量值的确切含义。（该定义与[RFC2330]和[RFC6390]中的性能指标一致）。
The procedure or set of operations having the object of determining a Measured Value or Measurement Result.
以确定测量值或测量结果为目的的程序或操作集。
See Section 2 of [RFC7011] for the definition of Observation Point (a location in the network where packets can be observed), and related definitions. The comparable term defined in IETF literature on Active measurement is "Measurement Point" (see Section 4.1 of [RFC5835]). Both of these terms have come into use describing similar actions at the identified point in the network path.
观测点（网络中可以观测数据包的位置）的定义和相关定义见[RFC7011]第2节。IETF文献中关于主动测量的可比术语为“测量点”（见[RFC5835]第4.1节）。这两个术语都用于描述网络路径中标识点处的类似操作。
Active Methods of Measurement have the following attributes:
主动测量方法具有以下属性：
o Active Methods generate packet streams. Commonly, the packet stream of interest is generated as the basis of measurement. Sometimes, the adjective "synthetic" is used to categorize Active measurement streams [Y.1731]. An accompanying packet stream or streams may be generated to increase overall traffic load, though the loading stream(s) may not be measured.
o 主动方法生成数据包流。通常，产生感兴趣的分组流作为测量的基础。有时，形容词“合成”用于对活动测量流进行分类[Y.1731]。可以生成伴随的一个或多个分组流以增加总体业务负载，尽管可以不测量加载流。
o The packets in the stream of interest have fields or field values (or are augmented or modified to include fields or field values) that are dedicated to measurement. Since measurement usually requires determining the corresponding packets at multiple measurement points, a sequence number is the most common information dedicated to measurement, and it is often combined with a timestamp.
o 感兴趣流中的分组具有专用于测量的字段或字段值（或被扩充或修改以包括字段或字段值）。由于测量通常需要在多个测量点确定相应的数据包，因此序列号是专用于测量的最常见信息，并且它通常与时间戳相结合。
o The Source and Destination of the packet stream of interest are usually known a priori.
o 感兴趣的分组流的源和目的地通常是先验的。
o The characteristics of the packet stream of interest are known at the Source (at least), and may be communicated to the Destination as part of the method. Note that some packet characteristics will normally change during packet forwarding. Other changes along the path are possible, see [STDFORM].
o 感兴趣的分组流的特征在源处（至少）是已知的，并且可以作为该方法的一部分被传送到目的地。请注意，在数据包转发过程中，某些数据包特征通常会发生变化。路径上的其他更改是可能的，请参见[STDFORM]。
When adding traffic to the network for measurement, Active Methods influence the quantities measured to some degree, and those performing tests should take steps to quantify the effect(s) and/or minimize such effects.
当向网络添加流量进行测量时，主动方法会在一定程度上影响测量量，执行测试的人员应采取措施量化影响和/或最小化此类影响。
An Active Metric incorporates one or more of the aspects of Active Methods in the metric definition.
活动度量包含度量定义中活动方法的一个或多个方面。
For example, IETF metrics for IP performance (developed according to the framework described in [RFC2330]) include the Source-packet stream characteristics as metric-input parameters, and also specify the packet characteristics (Type-P) and Source and Destination IP addresses (with their implications on both stream treatment and interfaces associated with measurement points).
例如，用于IP性能的IETF度量（根据[RFC2330]中描述的框架开发）包括源分组流特征作为度量输入参数，并且还指定分组特征（类型-P）以及源和目标IP地址（其对水流处理和与测量点相关的接口的影响）。
Passive Methods of Measurement are:
被动测量方法包括：
o based solely on observations of an undisturbed and unmodified packet stream of interest (in other words, the method of measurement MUST NOT add, change, or remove packets or fields or change field values anywhere along the path).
o 仅基于对未受干扰且未修改的感兴趣数据包流的观察（换句话说，测量方法不得添加、更改或删除数据包或字段，或更改路径上任何位置的字段值）。
o dependent on the existence of one or more packet streams to supply the stream of interest.
o 依赖于一个或多个分组流的存在来提供感兴趣的流。
o dependent on the presence of the packet stream of interest at one or more designated Observation Points.
o 取决于在一个或多个指定观察点处感兴趣的分组流的存在。
Some Passive Methods simply observe and collect information on all packets that pass Observation Point(s), while others filter the packets as a first step and only collect information on packets that match the filter criteria, and thereby narrow the stream of interest.
一些被动方法只是观察和收集通过观察点的所有数据包的信息，而另一些被动方法作为第一步过滤数据包，只收集符合过滤条件的数据包的信息，从而缩小感兴趣的流。
It is common that Passive Methods are conducted at one or more Observation Points. Passive Methods to assess Performance Metrics often require multiple Observation Points, e.g., to assess the latency of packet transfer across a network path between two Observation Points. In this case, the observed packets must include enough information to determine the corresponding packets at different Observation Points.
被动方法通常在一个或多个观测点进行。评估性能指标的被动方法通常需要多个观察点，例如，评估两个观察点之间网络路径上的数据包传输延迟。在这种情况下，观察到的分组必须包括足够的信息以确定不同观察点处的对应分组。
Communication of the observations (in some form) to a collector is an essential aspect of Passive Methods. In some configurations, the traffic load generated when communicating (or exporting) the Passive Method results to a collector may itself influence the measured network's performance. However, the collection of results is not unique to Passive Methods, and the load from management and operations of measurement systems must always be considered for potential effects on the measured values.
将观察结果（以某种形式）传达给收集器是被动方法的一个基本方面。在一些配置中，将被动方法结果传送（或导出）到收集器时产生的流量负载本身可能会影响被测网络的性能。然而，结果的收集并非被动方法所独有，必须始终考虑测量系统管理和操作的负载对测量值的潜在影响。
Passive Metrics apply to observations of packet traffic (traffic flows in [RFC7011]).
被动度量适用于数据包流量的观测（[RFC7011]中的流量）。
Passive performance metrics are assessed independently of the packets or traffic flows, and solely through observation. Some refer to such assessments as "out of band".
被动性能指标独立于数据包或流量进行评估，并且仅通过观察进行评估。有些人将此类评估称为“带外”。
One example of Passive Performance Metrics for IP packet transfer can be found in ITU-T Recommendation Y.1540 [Y.1540], where the metrics are defined on the basis of reference events generated as packets pass reference points. The metrics are agnostic to the distinction between Active and Passive when the necessary packet correspondence can be derived from the observed stream of interest as required.
IP数据包传输的被动性能指标的一个示例可以在ITU-T建议Y.1540[Y.1540]中找到，其中，这些指标是根据数据包通过参考点时生成的参考事件定义的。当必要的数据包对应可以根据需要从观察到的感兴趣的流中导出时，这些度量与主动和被动之间的区别是不可知的。
Hybrid Methods are Methods of Measurement that use a combination of Active Methods and Passive Methods, to assess Active Metrics, Passive Metrics, or new metrics derived from the a priori knowledge and observations of the stream of interest. ITU-T Recommendation Y.1540 [Y.1540] defines metrics that are also applicable to the hybrid categories, since packet correspondence at different observation/ reference points could be derived from "fields or field values which are dedicated to measurement", but otherwise the methods are Passive.
混合方法是使用主动方法和被动方法相结合的测量方法，用于评估主动度量、被动度量或从感兴趣流的先验知识和观察中得出的新度量。ITU-T建议Y.1540[Y.1540]定义了也适用于混合类别的指标，因为不同观测/参考点的数据包对应可以从“专用于测量的字段或字段值”中导出，但其他方法是被动的。
There are several types of Hybrid Methods, as categorized below.
有几种类型的混合方法，分类如下。
With respect to a *single* stream of interest, Hybrid Type I methods fit in the continuum as follows, in terms of what happens at the Source (or Observation Point nearby):
对于*单一*感兴趣的流，混合I型方法适用于连续统，如下所示，即在源（或附近的观测点）发生的情况：
o Generation of the stream of interest => Active
o 感兴趣流的生成=>活动
o Augmentation or modification of the stream of interest, or employment of methods that modify the treatment of the stream => Hybrid Type I
o 增加或修改感兴趣的流，或使用修改流处理的方法=>混合类型I
o Observation of a stream of interest => Passive
o 关注流的观察=>被动
As an example, consider the case where the method generates traffic load stream(s), and observes an existing stream of interest according to the criteria for Passive Methods. Since loading streams are an aspect of Active Methods, the stream of interest is not "solely observed", and the measurements involve a single stream of interest whose treatment has been modified by the presence of the load. Therefore, this is a Hybrid Type I method.
作为一个例子，考虑该方法产生流量负载流的情况，并根据被动方法的标准观察现有的感兴趣流。由于加载流是主动方法的一个方面，因此关注流不是“单独观察”的，并且测量涉及单个关注流，其处理已通过负载的存在而修改。因此，这是一种混合I型方法。
We define Hybrid Type II as follows: Methods that employ two or more different streams of interest with some degree of mutual coordination (e.g., one or more Active streams and one or more undisturbed and unmodified packet streams) to collect both Active and Passive Metrics and enable enhanced characterization from additional joint analysis. [HYBRID] presents a problem statement for Hybrid Type II Methods and Metrics. Note that one or more Hybrid Type I streams could be substituted for the Active streams or undisturbed streams in the mutually coordinated set. It is the Type II Methods where unique Hybrid Metrics are anticipated to emerge.
我们将混合类型II定义如下：采用两个或多个不同的感兴趣流并具有某种程度的相互协调（例如，一个或多个主动流和一个或多个未受干扰和未修改的数据包流）的方法，以收集主动和被动度量，并通过额外的联合分析实现增强的表征。[HYBRID]提出了混合II型方法和指标的问题陈述。注意，一个或多个混合I型流可替代相互协调集合中的活动流或未受干扰流。第二类方法预计会出现独特的混合指标。
Methods based on a combination of a single (generated) Active stream and Passive observations applied to the stream of interest at intermediate Observation Points are also Hybrid Methods. However, [RFC5644] already defines these as Spatial Metrics and Methods. It is possible to replace the Active stream of [RFC5644] with a Hybrid Type I stream and measure Spatial Metrics (but this was unanticipated when [RFC5644] was developed).
基于单个（生成的）主动流和被动观测组合的方法应用于中间观测点的感兴趣流，也是混合方法。然而，[RFC5644]已经将这些定义为空间度量和方法。可以将[RFC5644]的活动流替换为混合I型流，并测量空间度量（但这在[RFC5644]开发时是意料不到的）。
The table below illustrates the categorization of methods (where "Synthesis" refers to a combination of Active and Passive Method attributes).
下表说明了方法的分类（其中“综合”指主动和被动方法属性的组合）。
| Single Stream | Multiple Simultaneous
| of Interest | Streams of Interest
| | from Different Methods
====================================================================
Single Fundamental | Active or Passive |
Method | |
| Single Stream | Multiple Simultaneous
| of Interest | Streams of Interest
| | from Different Methods
====================================================================
Single Fundamental | Active or Passive |
Method | |
Synthesis of | Hybrid Type I |
Fundamental Methods | |
Synthesis of | Hybrid Type I |
Fundamental Methods | |
Multiple Methods | Spatial Metrics | Hybrid Type II | [RFC5644] |
多方法|空间度量|混合类型II |[RFC5644]|
There may be circumstances where results measured with Hybrid Methods can be considered equivalent to those measured with Passive Methods. This notion references the possibility of a "class C" where packets of different Type-P are treated equally in network implementation, as described in Section 13 of [RFC2330] and using the terminology for paths from Section 5 of [RFC2330]:
在某些情况下，使用混合方法测量的结果可能被视为等同于使用被动方法测量的结果。该概念引用了“C类”的可能性，其中不同类型P的数据包在网络实现中被同等对待，如[RFC2330]第13节所述，并使用[RFC2330]第5节中的路径术语：
Hybrid Methods of measurement that augment or modify packets of a "class C" in a host should produce results equivalent to Passive Methods of Measurement when hosts accessing and links transporting these packets along the path (other than those performing augmentation/modification) treat packets from both categories of
当主机访问和沿路径传输这些数据包的链路（除了执行增强/修改的链路）处理来自这两类数据包时，增加或修改主机中“C类”数据包的混合测量方法应产生与被动测量方法相同的结果
methods (with and without the augmentation/modification) as the same "class C". The Passive Methods of Measurement represent the Ground Truth when comparing results between Passive and Hybrid Methods, and this comparison should be conducted to confirm the "class C" treatment.
方法（有或没有增加/修改）与“C类”相同。在比较被动和混合方法的结果时，被动测量方法代表了基本事实，应进行此比较以确认“C级”处理。
This section illustrates the definitions and presents some examples.
本节说明了定义并给出了一些示例。
If we compare the Active and Passive Methods, there are at least two dimensions on which methods can be evaluated. This evaluation space may be useful when a method is a combination of the two alternative methods.
如果我们比较主动和被动方法，至少有两个维度可以对方法进行评估。当一种方法是两种可选方法的组合时，此评估空间可能很有用。
The two dimensions (initially chosen) are:
两个维度（最初选择）为：
Y-Axis: "Effect of the measured stream on network conditions". The degree to which the stream of interest biases overall network conditions experienced by that stream and other streams. This is a key dimension for Active measurement error analysis. (Comment: There is also the notion of time averages -- a measurement stream may have significant effect while it is present, but the stream is only generated 0.1% of the time. On the other hand, observations alone have no effect on network performance. To keep these dimensions simple, we consider the stream effect only when it is present, but note that reactive networks defined in [RFC7312] may exhibit bias for some time beyond the life of a stream.)
Y轴：“测量流对网络条件的影响”。兴趣流对该流和其他流所经历的整体网络条件的偏差程度。这是主动测量误差分析的关键维度。（注释：也有时间平均的概念——测量流在它存在的时候可能有显著的影响，但是流只产生0.1%的时间。另一方面，观察本身对网络性能没有影响。为了保持这些维度的简单性，我们仅在流存在时考虑流效应，但是注意。[RFC7312]中定义的无功网络可能会在超过流寿命的一段时间内出现偏差。）
X-Axis: "a priori Stream Knowledge". The degree to which stream characteristics are known a priori. There are methodological advantages of knowing the source stream characteristics, and having complete control of the stream characteristics. For example, knowing the number of packets in a stream allows more-efficient operation of the measurement receiver, and so is an asset for Active Methods of Measurement. Passive Methods (with no sample filter) have few clues available to anticipate what protocol the first packet observed will use or how many packets will comprise the flow; once the standard protocol of a flow is known, the possibilities narrow (for some compliant flows). Therefore, this is a key dimension for Passive measurement error analysis.
X轴：“先验知识流”。流特征的先验已知程度。了解源流特征和完全控制流特征具有方法学优势。例如，知道流中分组的数量允许测量接收器更有效地操作，因此是主动测量方法的资产。被动方法（没有样本过滤器）几乎没有可用的线索来预测观察到的第一个数据包将使用什么协议，或者有多少数据包将包含流；一旦知道流的标准协议，可能性就会缩小（对于某些兼容流）。因此，这是被动测量误差分析的一个关键维度。
There are a few examples we can plot on a two-dimensional space. We can anchor the dimensions with reference point descriptions.
我们可以在二维空间中绘制一些示例。我们可以使用参考点描述锚定尺寸。
Y-Axis:Effect of the measured stream on network conditions
^ Max
|* Active using max capacity stream
|
|
|
|
|* Active using stream with load of typical user
|
|
|
|* Active using extremely sparse, randomized stream
| * PDM Passive
| Min *
+----------------------------------------------------------------|
| |
Stream X-Axis: a priori Stream Knowledge No Stream
Characteristics Characteristics
Completely Known
Known
Y-Axis:Effect of the measured stream on network conditions
^ Max
|* Active using max capacity stream
|
|
|
|
|* Active using stream with load of typical user
|
|
|
|* Active using extremely sparse, randomized stream
| * PDM Passive
| Min *
+----------------------------------------------------------------|
| |
Stream X-Axis: a priori Stream Knowledge No Stream
Characteristics Characteristics
Completely Known
Known
(In the graph above, "PDM" refers to [PDMOPTION], an IPv6 Option Header for Performance and Diagnostic Measurements, described in Section 4.2.)
（在上图中，“PDM”指[PDMOPTION]，一个用于性能和诊断测量的IPv6选项标头，如第4.2节所述。）
We recognize that method categorization could be based on additional dimensions, but this would require a different graphical approach.
我们认识到方法分类可以基于其他维度，但这需要不同的图形方法。
For example, "effect of stream of interest on network conditions" could easily be further qualified into:
例如，“利益流对网络条件的影响”可以很容易地进一步限定为：
1. effect on the performance of the stream of interest itself: for example, choosing a packet marking or Differentiated Services Code Point (DSCP) resulting in domain treatment as a real-time stream (as opposed to default/best-effort marking).
1. 对感兴趣的流本身的性能的影响：例如，选择分组标记或区分服务代码点（DSCP），导致将域处理为实时流（与默认/尽力而为标记相反）。
2. effect on unmeasured streams that share the path and/or bottlenecks: for example, an extremely sparse measured stream of minimal size packets typically has little effect on other flows (and itself), while a stream designed to characterize path capacity may affect all other flows passing through the capacity bottleneck (including itself).
2. 对共享路径和/或瓶颈的未测量流的影响：例如，最小大小数据包的极稀疏测量流通常对其他流（和自身）影响不大，而设计用于表征路径容量的流可能会影响通过容量瓶颈（包括自身）的所有其他流。
3. effect on network conditions resulting in network adaptation: for example, a network monitoring load and congestion conditions might change routing, placing some flows on alternate paths to mitigate the congestion.
3. 对网络条件的影响导致网络自适应：例如，网络监控负载和拥塞条件可能会改变路由，将一些流放置在备用路径上以缓解拥塞。
We have combined 1 and 2 on the Y-axis, as examination of examples indicates strong correlation of the effects in this pair, and network adaptation is not addressed.
我们在Y轴上结合了1和2，因为示例检查表明，这一对中的效应具有很强的相关性，并且网络适应没有得到解决。
It is apparent that different methods of IP network measurement can produce different results, even when measuring the same path at the same time. The two dimensions of the graph help us to understand how the results might change with the method chosen. For example, an Active Method to assess throughput adds some amount of traffic to the network, which might result in lower throughput for all streams. However, a Passive Method to assess throughput can also err on the low side due to unknown limitations of the hosts providing traffic, competition for host resources, limitations of the network interface, or private sub-networks that are not an intentional part of the path, etc. Hybrid Methods could easily suffer from both forms of error. Another example of potential errors stems from the pitfalls of using an Active stream with known a bias, such as a periodic stream defined in [RFC3432]. The strength of modeling periodic streams (like Voice over IP (VoIP)) is a potential weakness when extending the measured results to other application whose streams are non-periodic. The solutions are to model the application streams more exactly with an Active Method or to accept the risks and potential errors with the Passive Method discussed above.
很明显，不同的IP网络测量方法可以产生不同的结果，即使在同时测量同一路径时也是如此。图形的两个维度帮助我们理解结果如何随所选方法而变化。例如，评估吞吐量的主动方法会向网络添加一定数量的流量，这可能会导致所有流的吞吐量降低。然而，由于提供流量的主机的未知限制、对主机资源的竞争、网络接口的限制或不是路径有意部分的专用子网等，评估吞吐量的被动方法也可能在低端出错。混合方法很容易受到这两种错误形式的影响。潜在错误的另一个示例源于使用具有已知偏差的活动流的陷阱，例如[RFC3432]中定义的周期流。在将测量结果扩展到流为非周期性的其他应用程序时，对周期性流（如IP语音（VoIP））建模的优势是一个潜在的弱点。解决方案是使用主动方法更精确地建模应用程序流，或者使用上面讨论的被动方法接受风险和潜在错误。
In [PDMOPTION], an IPv6 Option Header for Performance and Diagnostic Measurements (PDM) is described which, when added to the stream of interest at strategic interfaces, supports performance measurements. This method processes a user traffic stream and adds "fields which are dedicated to measurement" (the measurement intent is made clear in the title of this option). Thus:
在[PDMOPTION]中，描述了性能和诊断度量（PDM）的IPv6选项标头，当添加到战略接口的关注流中时，该标头支持性能度量。此方法处理用户流量流并添加“专用于测量的字段”（此选项的标题中明确了测量意图）。因此：
o The method intends to have a minor effect on the measured stream and other streams in the network. There are conditions where this intent may not be realized.
o 该方法旨在对测量流和网络中的其他流产生较小的影响。在某些情况下，这一意图可能无法实现。
o The measured stream has unknown characteristics until it is processed to add the PDM Option header. Note that if the packet MTU is exceeded after adding the header, the intent to have a minor effect will not be realized.
o 测量的流具有未知的特征，直到它被处理以添加PDM选项标题。注意，如果在添加报头之后超过了分组MTU，则不会实现产生次要影响的意图。
We conclude that this is a Hybrid Type I method, having at least one characteristic of both Active and Passive Methods for a single stream of interest.
我们得出结论，这是一种混合I型方法，对于单个感兴趣的流，至少具有主动和被动方法的一个特征。
[OPSAWG], proposed to color packets by re-writing a field of the stream at strategic interfaces to support performance measurements (noting that this is a difficult operation at an intermediate point on an encrypted Virtual Private Network). This method processes a user traffic stream and inserts "fields or values which are dedicated to measurement". Thus:
[OPSAWG]建议通过在战略接口处重新写入流字段来对数据包进行着色，以支持性能测量（注意，在加密虚拟专用网络的中间点上，这是一个困难的操作）。此方法处理用户流量流并插入“专用于测量的字段或值”。因此：
o The method intends to have a minor effect on the measured stream and other streams in the network (less than PDM above). There are conditions where this intent may not be realized.
o 该方法旨在对测量流和网络中的其他流产生较小的影响（小于上述PDM）。在某些情况下，这一意图可能无法实现。
o The measured stream has unknown characteristics until it is processed to add the coloring in the header, and the stream could be measured and time-stamped during that process.
o 测量的流具有未知的特征，直到它被处理以在报头中添加颜色，并且在该过程中可以测量流并对其进行时间戳。
We note that [COLORING] proposes a method similar to [OPSAWG], as discussion on the IPPM mailing list revealed.
我们注意到，[COLORING]提出了一种类似于[OPSAWG]的方法，正如IPPM邮件列表上的讨论所揭示的那样。
We conclude that this is a Hybrid Type I method, having at least one characteristic of both Active and Passive Methods for a single stream of interest.
我们得出结论，这是一种混合I型方法，对于单个感兴趣的流，至少具有主动和被动方法的一个特征。
Many Operations, Administration, and Management (OAM) methods exist beyond the IP layer. For example, [Y.1731] defines several different measurement methods that we would classify as follows:
许多操作、管理和管理（OAM）方法存在于IP层之外。例如，[Y.1731]定义了几种不同的测量方法，我们将其分类如下：
o Loss Measurement (LM) occasionally injects frames with a count of previous frames since the last LM message. We conclude LM is Hybrid Type I, because this method processes a user traffic stream and augments the stream of interest with frames having "fields which are dedicated to measurement".
o 损耗测量（LM）偶尔会使用自上次LM消息以来的前一帧计数注入帧。我们认为LM是混合类型I，因为该方法处理用户流量流，并使用具有“专用于测量的字段”的帧来增强感兴趣的流。
o Synthetic Loss Measurement (SLM) and Delay Measurement (DM) methods both inject dedicated measurement frames, so the "stream of interest is generated as the basis of measurement". We conclude that SLM and DM methods are Active Methods.
o 合成损耗测量（SLM）和延迟测量（DM）方法都注入专用的测量帧，因此“产生感兴趣的流作为测量的基础”。我们得出结论，SLM和DM方法是有效的方法。
We also recognize the existence of alternate terminology used in OAM at layers other than IP. Readers are encouraged to consult [RFC6374] for MPLS Loss and Delay measurement terminology, for example.
我们还认识到，OAM在IP以外的层中使用了替代术语。例如，鼓励读者参考[RFC6374]了解MPLS丢失和延迟测量术语。
When considering the security and privacy of those involved in measurement or those whose traffic is measured, there is sensitive information communicated and observed at observation and measurement points described above, and protocol issues to consider. We refer the reader to the security and privacy considerations described in the Large-Scale Measurement of Broadband Performance (LMAP) Framework [RFC7594], which covers Active and Passive measurement techniques and supporting material on measurement context.
当考虑涉及测量的人的安全性和隐私或测量交通量时，在上述观测和测量点上有通信和观察的敏感信息，以及要考虑的协议问题。我们建议读者参考大规模宽带性能测量（LMAP）框架[RFC7594]中描述的安全和隐私注意事项，该框架涵盖主动和被动测量技术以及测量上下文的支持材料。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <http://www.rfc-editor.org/info/rfc2119>.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，DOI 10.17487/RFC2119，1997年3月<http://www.rfc-editor.org/info/rfc2119>.
[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis, "Framework for IP Performance Metrics", RFC 2330, DOI 10.17487/RFC2330, May 1998, <http://www.rfc-editor.org/info/rfc2330>.
[RFC2330]Paxson，V.，Almes，G.，Mahdavi，J.，和M.Mathis，“IP性能度量框架”，RFC 2330，DOI 10.17487/RFC2330，1998年5月<http://www.rfc-editor.org/info/rfc2330>.
[RFC3432] Raisanen, V., Grotefeld, G., and A. Morton, "Network performance measurement with periodic streams", RFC 3432, DOI 10.17487/RFC3432, November 2002, <http://www.rfc-editor.org/info/rfc3432>.
[RFC3432]Raisanen，V.，Grotefeld，G.，和A.Morton，“周期流的网络性能测量”，RFC 3432，DOI 10.17487/RFC3432，2002年11月<http://www.rfc-editor.org/info/rfc3432>.
[RFC5644] Stephan, E., Liang, L., and A. Morton, "IP Performance Metrics (IPPM): Spatial and Multicast", RFC 5644, DOI 10.17487/RFC5644, October 2009, <http://www.rfc-editor.org/info/rfc5644>.
[RFC5644]Stephan，E.，Liang，L.，和A.Morton，“IP性能度量（IPPM）：空间和多播”，RFC 5644，DOI 10.17487/RFC5644，2009年10月<http://www.rfc-editor.org/info/rfc5644>.
[RFC5835] Morton, A., Ed. and S. Van den Berghe, Ed., "Framework for Metric Composition", RFC 5835, DOI 10.17487/RFC5835, April 2010, <http://www.rfc-editor.org/info/rfc5835>.
[RFC5835]Morton，A.，Ed.和S.Van den Berghe，Ed.，“公制组合框架”，RFC 5835，DOI 10.17487/RFC5835，2010年4月<http://www.rfc-editor.org/info/rfc5835>.
[RFC6390] Clark, A. and B. Claise, "Guidelines for Considering New Performance Metric Development", BCP 170, RFC 6390, DOI 10.17487/RFC6390, October 2011, <http://www.rfc-editor.org/info/rfc6390>.
[RFC6390]Clark，A.和B.Claise，“考虑新绩效指标开发的指南”，BCP 170，RFC 6390，DOI 10.17487/RFC6390，2011年10月<http://www.rfc-editor.org/info/rfc6390>.
[RFC7011] Claise, B., Ed., Trammell, B., Ed., and P. Aitken, "Specification of the IP Flow Information Export (IPFIX) Protocol for the Exchange of Flow Information", STD 77, RFC 7011, DOI 10.17487/RFC7011, September 2013, <http://www.rfc-editor.org/info/rfc7011>.
[RFC7011]Claise，B.，Ed.，Trammell，B.，Ed.，和P.Aitken，“流量信息交换的IP流量信息导出（IPFIX）协议规范”，STD 77，RFC 7011，DOI 10.17487/RFC7011，2013年9月<http://www.rfc-editor.org/info/rfc7011>.
[RFC7312] Fabini, J. and A. Morton, "Advanced Stream and Sampling Framework for IP Performance Metrics (IPPM)", RFC 7312, DOI 10.17487/RFC7312, August 2014, <http://www.rfc-editor.org/info/rfc7312>.
[RFC7312]Fabini，J.和A.Morton，“IP性能度量的高级流和采样框架（IPPM）”，RFC 7312，DOI 10.17487/RFC7312，2014年8月<http://www.rfc-editor.org/info/rfc7312>.
[RFC7594] Eardley, P., Morton, A., Bagnulo, M., Burbridge, T., Aitken, P., and A. Akhter, "A Framework for Large-Scale Measurement of Broadband Performance (LMAP)", RFC 7594, DOI 10.17487/RFC7594, September 2015, <http://www.rfc-editor.org/info/rfc7594>.
[RFC7594]Eardley，P.，Morton，A.，Bagnulo，M.，Burbridge，T.，Aitken，P.，和A.Akhter，“宽带性能的大规模测量框架（LMAP）”，RFC 7594，DOI 10.17487/RFC7594，2015年9月<http://www.rfc-editor.org/info/rfc7594>.
[COLORING] Chen, M., Ed., Zheng, L., Ed., Mirsky, G., Ed., Fioccola, G., Ed., and T. Mizrahi, Ed., "IP Flow Performance Measurement Framework", Work in Progress, draft-chen-ippm-coloring-based-ipfpm-framework-06, March 2016.
[COLORING]Chen，M.，Ed.，Zheng，L.，Ed.，Mirsky，G.，Ed.，Fioccola，G.，Ed.，和T.Mizrahi，Ed.，“IP流性能测量框架”，正在进行的工作，草稿-Chen-ippm-COLORING-based-ipfpm-Framework-062016年3月。
[HYBRID] Trammell, B., Zheng, L., Berenguer, S., and M. Bagnulo, "Hybrid Measurement using IPPM Metrics", Work in Progress, draft-trammell-ippm-hybrid-ps-01, February 2014.
[HYBRID]Trammell，B.，Zheng，L.，Berenguer，S.，和M.Bagnulo，“使用IPPM度量的混合测量”，正在进行的工作，草稿-Trammell-IPPM-HYBRID-ps-012014年2月。
[OPSAWG] Capello, A., Cociglio, M., Castaldelli, L., and A. Bonda, "A packet based method for passive performance monitoring", Work in Progress, draft-tempia-opsawg-p3m-04, February 2014.
[OPSAWG]卡佩罗，A.，科奇廖，M.，卡斯塔尔德利，L.，和A.邦达，“一种基于数据包的被动性能监控方法”，在建工程，草稿-tempia-OPSAWG-p3m-042014年2月。
[PASSIVE] Zheng, L., Elkins, N., Lingli, D., Ackermann, M., and G. Mirsky, "Framework for IP Passive Performance Measurements", Work in Progress, draft-zheng-ippm-framework-passive-03, February 2015.
[被动]Zheng，L.，Elkins，N.，Lingli，D.，Ackermann，M.，和G.Mirsky，“IP被动性能测量框架”，正在进行的工作，草稿-Zheng-ippm-Framework-PASSIVE-032015年2月。
[PDMOPTION] Elkins, N. and M. Ackermann, "IPv6 Performance and Diagnostic Metrics (PDM) Destination Option", Work in Progress, draft-ietf-ippm-6man-pdm-option-02, April 2016.
[PDMOPTION]Elkins，N.和M.Ackermann，“IPv6性能和诊断指标（PDM）目标选项”，正在进行的工作，草稿-ietf-ippm-6man-PDM-Option-022016年4月。
[RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay Measurement for MPLS Networks", RFC 6374, DOI 10.17487/RFC6374, September 2011, <http://www.rfc-editor.org/info/rfc6374>.
[RFC6374]Frost，D.和S.Bryant，“MPLS网络的数据包丢失和延迟测量”，RFC 6374，DOI 10.17487/RFC6374，2011年9月<http://www.rfc-editor.org/info/rfc6374>.
[STDFORM] Morton, A., Fabini, J., Elkins, N., Ackermann, M., and V. Hegde, "Updates for IPPM's Active Metric Framework: Packets of Type-P and Standard-Formed Packets", Work in Progress, draft-morton-ippm-2330-stdform-typep-02, December 2015.
[STDFORM]Morton，A.，Fabini，J.，Elkins，N.，Ackermann，M.，和V.Hegde，“IPPM主动度量框架的更新：P型数据包和标准格式数据包”，正在进行的工作，草稿-Morton-IPPM-2330-STDFORM-typep-022015年12月。
[Y.1540] ITU-T, "Internet protocol data communication service - IP packet transfer and availability performance parameters", March 2011, <https://www.itu.int/rec/T-REC-Y.1540-201103-I/en>.
[Y.1540]ITU-T，“互联网协议数据通信服务-IP数据包传输和可用性性能参数”，2011年3月<https://www.itu.int/rec/T-REC-Y.1540-201103-I/en>.
[Y.1731] ITU-T, "Operation, administration and management (OAM) functions and mechanisms for Ethernet-based networks", August 2015, <https://www.itu.int/rec/T-REC-G.8013-201508-I/en>.
[Y.1731]ITU-T，“基于以太网的网络的运营、管理和管理（OAM）功能和机制”，2015年8月<https://www.itu.int/rec/T-REC-G.8013-201508-I/en>.
Acknowledgements
致谢
Thanks to Mike Ackermann for asking the right question, and for several suggestions on terminology. Brian Trammell provided key terms and references for the Passive category, and suggested ways to expand the Hybrid description and types. Phil Eardley suggested some hybrid scenarios for categorization as part of his review. Tiziano Ionta reviewed the document and suggested the classification for the "coloring" Method of Measurement. Nalini Elkins identified several areas for clarification following her review. Bill Jouris, Stenio Fernandes, and Spencer Dawkins suggested several editorial improvements. Tal Mizrahi, Joachim Fabini, Greg Mirsky, and Mike Ackermann raised many key considerations in their Working Group Last Call (WGLC) reviews, based on their broad measurement experience.
感谢迈克·阿克曼提出了正确的问题，并就术语提出了一些建议。Brian Trammell提供了被动类别的关键术语和参考，并提出了扩展混合描述和类型的方法。Phil Eardley提出了一些混合的分类方案，作为其评论的一部分。Tiziano Ionta审查了该文件，并提出了“着色”测量方法的分类。Nalini Elkins在审查后确定了几个需要澄清的领域。Bill Jouris、Stenio Fernandes和Spencer Dawkins提出了几项编辑改进建议。Tal Mizrahi、Joachim Fabini、Greg Mirsky和Mike Ackermann根据其广泛的测量经验，在其工作组最后一次通话（WGLC）审查中提出了许多关键考虑因素。
Author's Address
作者地址
Al Morton AT&T Labs 200 Laurel Avenue South Middletown, NJ United States
美国新泽西州劳雷尔大道南米德尔顿200号艾尔莫顿AT&T实验室
Email: acmorton@att.com
Email: acmorton@att.com