Internet Engineering Task Force (IETF) S. Poretsky
Request for Comments: 6413 Allot Communications
Category: Informational B. Imhoff
ISSN: 2070-1721 Juniper Networks
K. Michielsen
Cisco Systems
November 2011
Internet Engineering Task Force (IETF) S. Poretsky
Request for Comments: 6413 Allot Communications
Category: Informational B. Imhoff
ISSN: 2070-1721 Juniper Networks
K. Michielsen
Cisco Systems
November 2011
Benchmarking Methodology for Link-State IGP Data-Plane Route Convergence
链路状态IGP数据平面路由收敛的基准测试方法
Abstract
摘要
This document describes the methodology for benchmarking Link-State Interior Gateway Protocol (IGP) Route Convergence. The methodology is to be used for benchmarking IGP convergence time through externally observable (black-box) data-plane measurements. The methodology can be applied to any link-state IGP, such as IS-IS and OSPF.
本文档描述了链路状态内部网关协议（IGP）路由收敛的基准测试方法。该方法用于通过外部可观测（黑箱）数据平面测量基准IGP收敛时间。该方法可应用于任何链路状态IGP，如IS-IS和OSPF。
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/rfc6413.
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/rfc6413.
Copyright Notice
版权公告
Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2011 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
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简化的BSD许可证文本，如本规范第4.e节所述
the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
如简化的BSD许可证所述，信托法律条款和许可证不提供任何担保。
This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English.
本文件可能包含2008年11月10日之前发布或公开的IETF文件或IETF贡献中的材料。控制某些材料版权的人员可能未授予IETF信托允许在IETF标准流程之外修改此类材料的权利。在未从控制此类材料版权的人员处获得充分许可的情况下，不得在IETF标准流程之外修改本文件，也不得在IETF标准流程之外创建其衍生作品，除了将其格式化以RFC形式发布或将其翻译成英语以外的其他语言。
Table of Contents
目录
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Factors for IGP Route Convergence Time . . . . . . . . . . 4
1.3. Use of Data Plane for IGP Route Convergence
Benchmarking . . . . . . . . . . . . . . . . . . . . . . . 5
1.4. Applicability and Scope . . . . . . . . . . . . . . . . . 6
2. Existing Definitions . . . . . . . . . . . . . . . . . . . . . 6
3. Test Topologies . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Test Topology for Local Changes . . . . . . . . . . . . . 7
3.2. Test Topology for Remote Changes . . . . . . . . . . . . . 8
3.3. Test Topology for Local ECMP Changes . . . . . . . . . . . 10
3.4. Test Topology for Remote ECMP Changes . . . . . . . . . . 11
3.5. Test topology for Parallel Link Changes . . . . . . . . . 11
4. Convergence Time and Loss of Connectivity Period . . . . . . . 12
4.1. Convergence Events without Instant Traffic Loss . . . . . 13
4.2. Loss of Connectivity (LoC) . . . . . . . . . . . . . . . . 16
5. Test Considerations . . . . . . . . . . . . . . . . . . . . . 17
5.1. IGP Selection . . . . . . . . . . . . . . . . . . . . . . 17
5.2. Routing Protocol Configuration . . . . . . . . . . . . . . 17
5.3. IGP Topology . . . . . . . . . . . . . . . . . . . . . . . 17
5.4. Timers . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.5. Interface Types . . . . . . . . . . . . . . . . . . . . . 18
5.6. Offered Load . . . . . . . . . . . . . . . . . . . . . . . 18
5.7. Measurement Accuracy . . . . . . . . . . . . . . . . . . . 19
5.8. Measurement Statistics . . . . . . . . . . . . . . . . . . 20
5.9. Tester Capabilities . . . . . . . . . . . . . . . . . . . 20
6. Selection of Convergence Time Benchmark Metrics and Methods . 20
6.1. Loss-Derived Method . . . . . . . . . . . . . . . . . . . 21
6.1.1. Tester Capabilities . . . . . . . . . . . . . . . . . 21
6.1.2. Benchmark Metrics . . . . . . . . . . . . . . . . . . 21
6.1.3. Measurement Accuracy . . . . . . . . . . . . . . . . . 21
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Factors for IGP Route Convergence Time . . . . . . . . . . 4
1.3. Use of Data Plane for IGP Route Convergence
Benchmarking . . . . . . . . . . . . . . . . . . . . . . . 5
1.4. Applicability and Scope . . . . . . . . . . . . . . . . . 6
2. Existing Definitions . . . . . . . . . . . . . . . . . . . . . 6
3. Test Topologies . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Test Topology for Local Changes . . . . . . . . . . . . . 7
3.2. Test Topology for Remote Changes . . . . . . . . . . . . . 8
3.3. Test Topology for Local ECMP Changes . . . . . . . . . . . 10
3.4. Test Topology for Remote ECMP Changes . . . . . . . . . . 11
3.5. Test topology for Parallel Link Changes . . . . . . . . . 11
4. Convergence Time and Loss of Connectivity Period . . . . . . . 12
4.1. Convergence Events without Instant Traffic Loss . . . . . 13
4.2. Loss of Connectivity (LoC) . . . . . . . . . . . . . . . . 16
5. Test Considerations . . . . . . . . . . . . . . . . . . . . . 17
5.1. IGP Selection . . . . . . . . . . . . . . . . . . . . . . 17
5.2. Routing Protocol Configuration . . . . . . . . . . . . . . 17
5.3. IGP Topology . . . . . . . . . . . . . . . . . . . . . . . 17
5.4. Timers . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.5. Interface Types . . . . . . . . . . . . . . . . . . . . . 18
5.6. Offered Load . . . . . . . . . . . . . . . . . . . . . . . 18
5.7. Measurement Accuracy . . . . . . . . . . . . . . . . . . . 19
5.8. Measurement Statistics . . . . . . . . . . . . . . . . . . 20
5.9. Tester Capabilities . . . . . . . . . . . . . . . . . . . 20
6. Selection of Convergence Time Benchmark Metrics and Methods . 20
6.1. Loss-Derived Method . . . . . . . . . . . . . . . . . . . 21
6.1.1. Tester Capabilities . . . . . . . . . . . . . . . . . 21
6.1.2. Benchmark Metrics . . . . . . . . . . . . . . . . . . 21
6.1.3. Measurement Accuracy . . . . . . . . . . . . . . . . . 21
6.2. Rate-Derived Method . . . . . . . . . . . . . . . . . . . 22
6.2.1. Tester Capabilities . . . . . . . . . . . . . . . . . 22
6.2.2. Benchmark Metrics . . . . . . . . . . . . . . . . . . 23
6.2.3. Measurement Accuracy . . . . . . . . . . . . . . . . . 23
6.3. Route-Specific Loss-Derived Method . . . . . . . . . . . . 24
6.3.1. Tester Capabilities . . . . . . . . . . . . . . . . . 24
6.3.2. Benchmark Metrics . . . . . . . . . . . . . . . . . . 24
6.3.3. Measurement Accuracy . . . . . . . . . . . . . . . . . 24
7. Reporting Format . . . . . . . . . . . . . . . . . . . . . . . 25
8. Test Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 26
8.1. Interface Failure and Recovery . . . . . . . . . . . . . . 27
8.1.1. Convergence Due to Local Interface Failure and
Recovery . . . . . . . . . . . . . . . . . . . . . . . 27
8.1.2. Convergence Due to Remote Interface Failure and
Recovery . . . . . . . . . . . . . . . . . . . . . . . 28
8.1.3. Convergence Due to ECMP Member Local Interface
Failure and Recovery . . . . . . . . . . . . . . . . . 30
8.1.4. Convergence Due to ECMP Member Remote Interface
Failure and Recovery . . . . . . . . . . . . . . . . . 31
8.1.5. Convergence Due to Parallel Link Interface Failure
and Recovery . . . . . . . . . . . . . . . . . . . . . 32
8.2. Other Failures and Recoveries . . . . . . . . . . . . . . 33
8.2.1. Convergence Due to Layer 2 Session Loss and
Recovery . . . . . . . . . . . . . . . . . . . . . . . 33
8.2.2. Convergence Due to Loss and Recovery of IGP
Adjacency . . . . . . . . . . . . . . . . . . . . . . 34
8.2.3. Convergence Due to Route Withdrawal and
Re-Advertisement . . . . . . . . . . . . . . . . . . . 35
8.3. Administrative Changes . . . . . . . . . . . . . . . . . . 37
8.3.1. Convergence Due to Local Interface Administrative
Changes . . . . . . . . . . . . . . . . . . . . . . . 37
8.3.2. Convergence Due to Cost Change . . . . . . . . . . . . 38
9. Security Considerations . . . . . . . . . . . . . . . . . . . 39
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 40
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 40
11.1. Normative References . . . . . . . . . . . . . . . . . . . 40
11.2. Informative References . . . . . . . . . . . . . . . . . . 41
6.2. Rate-Derived Method . . . . . . . . . . . . . . . . . . . 22
6.2.1. Tester Capabilities . . . . . . . . . . . . . . . . . 22
6.2.2. Benchmark Metrics . . . . . . . . . . . . . . . . . . 23
6.2.3. Measurement Accuracy . . . . . . . . . . . . . . . . . 23
6.3. Route-Specific Loss-Derived Method . . . . . . . . . . . . 24
6.3.1. Tester Capabilities . . . . . . . . . . . . . . . . . 24
6.3.2. Benchmark Metrics . . . . . . . . . . . . . . . . . . 24
6.3.3. Measurement Accuracy . . . . . . . . . . . . . . . . . 24
7. Reporting Format . . . . . . . . . . . . . . . . . . . . . . . 25
8. Test Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 26
8.1. Interface Failure and Recovery . . . . . . . . . . . . . . 27
8.1.1. Convergence Due to Local Interface Failure and
Recovery . . . . . . . . . . . . . . . . . . . . . . . 27
8.1.2. Convergence Due to Remote Interface Failure and
Recovery . . . . . . . . . . . . . . . . . . . . . . . 28
8.1.3. Convergence Due to ECMP Member Local Interface
Failure and Recovery . . . . . . . . . . . . . . . . . 30
8.1.4. Convergence Due to ECMP Member Remote Interface
Failure and Recovery . . . . . . . . . . . . . . . . . 31
8.1.5. Convergence Due to Parallel Link Interface Failure
and Recovery . . . . . . . . . . . . . . . . . . . . . 32
8.2. Other Failures and Recoveries . . . . . . . . . . . . . . 33
8.2.1. Convergence Due to Layer 2 Session Loss and
Recovery . . . . . . . . . . . . . . . . . . . . . . . 33
8.2.2. Convergence Due to Loss and Recovery of IGP
Adjacency . . . . . . . . . . . . . . . . . . . . . . 34
8.2.3. Convergence Due to Route Withdrawal and
Re-Advertisement . . . . . . . . . . . . . . . . . . . 35
8.3. Administrative Changes . . . . . . . . . . . . . . . . . . 37
8.3.1. Convergence Due to Local Interface Administrative
Changes . . . . . . . . . . . . . . . . . . . . . . . 37
8.3.2. Convergence Due to Cost Change . . . . . . . . . . . . 38
9. Security Considerations . . . . . . . . . . . . . . . . . . . 39
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 40
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 40
11.1. Normative References . . . . . . . . . . . . . . . . . . . 40
11.2. Informative References . . . . . . . . . . . . . . . . . . 41
Convergence time is a critical performance parameter. Service Providers use IGP convergence time as a key metric of router design and architecture. Fast network convergence can be optimally achieved through deployment of fast converging routers. Customers of Service Providers use packet loss due to Interior Gateway Protocol (IGP) convergence as a key metric of their network service quality. IGP route convergence is a Direct Measure of Quality (DMOQ) when benchmarking the data plane. The fundamental basis by which network users and operators benchmark convergence is packet loss and other packet impairments, which are externally observable events having direct impact on their application performance. For this reason, it is important to develop a standard methodology for benchmarking link-state IGP convergence time through externally observable (black-box) data-plane measurements. All factors contributing to convergence time are accounted for by measuring on the data plane.
收敛时间是一个关键性能参数。服务提供商使用IGP收敛时间作为路由器设计和架构的关键指标。快速网络融合可以通过部署快速融合路由器来实现。服务提供商的客户将由于内部网关协议（IGP）融合而导致的数据包丢失作为其网络服务质量的关键指标。在对数据平面进行基准测试时，IGP路由收敛是质量的直接度量（DMOQ）。网络用户和运营商对融合进行基准测试的基本依据是数据包丢失和其他数据包损坏，它们是直接影响其应用程序性能的外部可观察事件。因此，通过外部可观测（黑箱）数据平面测量，制定链路状态IGP收敛时间基准的标准方法非常重要。所有影响收敛时间的因素都是通过在数据平面上测量得到的。
There are four major categories of factors contributing to the measured IGP convergence time. As discussed in [Vi02], [Ka02], [Fi02], [Al00], [Al02], and [Fr05], these categories are Event Detection, Shortest Path First (SPF) Processing, Link State Advertisement (LSA) / Link State Packet (LSP) Advertisement, and Forwarding Information Base (FIB) Update. These have numerous components that influence the convergence time, including but not limited to the list below:
有四大类因素影响测量的IGP收敛时间。如[Vi02]、[Ka02]、[Fi02]、[Al00]、[Al02]和[Fr05]中所述，这些类别是事件检测、最短路径优先（SPF）处理、链路状态播发（LSA）/链路状态包（LSP）播发和转发信息库（FIB）更新。影响收敛时间的因素很多，包括但不限于以下列表：
o Event Detection
o 事件检测
* Physical-Layer Failure/Recovery Indication Time
* 物理层故障/恢复指示时间
* Layer 2 Failure/Recovery Indication Time
* 第2层故障/恢复指示时间
* IGP Hello Dead Interval
* 你好死区间
o SPF Processing
o SPF处理
* SPF Delay Time
* SPF延迟时间
* SPF Hold Time
* SPF保持时间
* SPF Execution Time
* SPF执行时间
o LSA/LSP Advertisement
o LSA/LSP广告
* LSA/LSP Generation Time
* LSA/LSP生成时间
* LSA/LSP Flood Packet Pacing
* LSA/LSP泛洪数据包调整
* LSA/LSP Retransmission Packet Pacing
* LSA/LSP重传分组调整
o FIB Update
o FIB更新
* Tree Build Time
* 树构建时间
* Hardware Update Time
* 硬件更新时间
o Increased Forwarding Delay due to Queueing
o 排队导致转发延迟增加
The contribution of each of the factors listed above will vary with each router vendor's architecture and IGP implementation. Routers may have a centralized forwarding architecture, in which one forwarding table is calculated and referenced for all arriving packets, or a distributed forwarding architecture, in which the central forwarding table is calculated and distributed to the interfaces for local look-up as packets arrive. The distributed forwarding tables are typically maintained (loaded and changed) in software.
上面列出的每一个因素的贡献都会因每个路由器供应商的架构和IGP实现而有所不同。路由器可以具有集中式转发体系结构，其中为所有到达的分组计算和引用一个转发表，或者具有分布式转发体系结构，其中在分组到达时计算中央转发表并将其分发到接口以进行本地查找。分布式转发表通常在软件中维护（加载和更改）。
The variation in router architecture and implementation necessitates the design of a convergence test that considers all of these components contributing to convergence time and is independent of the Device Under Test (DUT) architecture and implementation. The benefit of designing a test for these considerations is that it enables black-box testing in which knowledge of the routers' internal implementation is not required. It is then possible to make valid use of the convergence benchmarking metrics when comparing routers from different vendors.
路由器体系结构和实现的变化要求设计一个收敛测试，该测试考虑所有这些组件对收敛时间的影响，并且独立于被测设备（DUT）体系结构和实现。为这些考虑因素设计测试的好处是，它支持不需要了解路由器内部实现的黑盒测试。然后，在比较来自不同供应商的路由器时，可以有效地使用收敛基准度量。
Convergence performance is tightly linked to the number of tasks a router has to deal with. As the most important tasks are mainly related to the control plane and the data plane, the more the DUT is stressed as in a live production environment, the closer performance measurement results match the ones that would be observed in a live production environment.
收敛性能与路由器必须处理的任务数量密切相关。由于最重要的任务主要与控制平面和数据平面有关，在现场生产环境中，DUT受到的压力越大，性能测量结果就越接近现场生产环境中观察到的结果。
Customers of Service Providers use packet loss and other packet impairments as metrics to calculate convergence time. Packet loss and other packet impairments are externally observable events having
服务提供商的客户使用数据包丢失和其他数据包损坏作为度量来计算收敛时间。数据包丢失和其他数据包损坏是具有以下特征的外部可观察事件：
direct impact on customers' application performance. For this reason, it is important to develop a standard router benchmarking methodology that is a Direct Measure of Quality (DMOQ) for measuring IGP convergence. An additional benefit of using packet loss for calculation of IGP Route Convergence time is that it enables black-box tests to be designed. Data traffic can be offered to the Device Under Test (DUT), an emulated network event can be forced to occur, and packet loss and other impaired packets can be externally measured to calculate the convergence time. Knowledge of the DUT architecture and IGP implementation is not required. There is no need to rely on the DUT to produce the test results. There is no need to build intrusive test harnesses for the DUT. All factors contributing to convergence time are accounted for by measuring on the data plane.
直接影响客户的应用程序性能。因此，开发一种标准路由器基准测试方法非常重要，该方法是衡量IGP收敛性的直接质量度量（DMOQ）。使用包丢失计算IGP路由收敛时间的另一个好处是，它可以设计黑盒测试。可以向被测设备（DUT）提供数据流量，可以强制发生模拟网络事件，并且可以从外部测量数据包丢失和其他受损数据包，以计算收敛时间。不需要具备DUT架构和IGP实施的知识。无需依赖DUT产生测试结果。无需为DUT构建侵入式测试线束。所有影响收敛时间的因素都是通过在数据平面上测量得到的。
Other work of the Benchmarking Methodology Working Group (BMWG) focuses on characterizing single router control-plane convergence. See [Ma05], [Ma05t], and [Ma05c].
基准测试方法工作组（BMWG）的其他工作侧重于描述单路由器控制平面的收敛性。参见[Ma05]、[Ma05t]和[Ma05c]。
The methodology described in this document can be applied to IPv4 and IPv6 traffic and link-state IGPs such as IS-IS [Ca90][Ho08], OSPF [Mo98][Co08], and others. IGP adjacencies established over any kind of tunnel (such as Traffic Engineering tunnels) are outside the scope of this document. Convergence time benchmarking in topologies with IGP adjacencies that are not point-to-point will be covered in a later document. Convergence from Bidirectional Forwarding Detection (BFD) is outside the scope of this document. Non-Stop Forwarding (NSF), Non-Stop Routing (NSR), Graceful Restart (GR), and any other High Availability mechanism are outside the scope of this document. Fast reroute mechanisms such as IP Fast-Reroute [Sh10i] or MPLS Fast-Reroute [Pa05] are outside the scope of this document.
本文档中描述的方法可应用于IPv4和IPv6流量和链路状态IGP，如IS-IS[Ca90][Ho08]、OSPF[Mo98][Co08]等。在任何类型的隧道（如交通工程隧道）上建立的IGP邻接不在本文件范围内。具有非点到点IGP邻接的拓扑中的收敛时间基准测试将在后面的文档中介绍。双向转发检测（BFD）的收敛不在本文档的范围内。不停止转发（NSF）、不停止路由（NSR）、优雅重启（GR）和任何其他高可用性机制不在本文档的范围内。IP快速重路由[Sh10i]或MPLS快速重路由[Pa05]等快速重路由机制不在本文档范围内。
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, RFC 2119 [Br97]. RFC 2119 defines the use of these keywords to help make the intent of Standards Track documents as clear as possible. While this document uses these keywords, this document is not a Standards Track document.
本文件中的关键词“必须”、“不得”、“要求”、“应”、“不得”、“应”、“不应”、“建议”、“可”和“可选”应按照BCP 14、RFC 2119[Br97]中的描述进行解释。RFC 2119定义了这些关键字的使用，以帮助使标准跟踪文档的意图尽可能清晰。虽然本文档使用这些关键字，但本文档不是标准跟踪文档。
This document uses much of the terminology defined in [Po11t]. For any conflicting content, this document supersedes [Po11t]. This document uses existing terminology defined in other documents issued by the Benchmarking Methodology Working Group (BMWG). Examples include, but are not limited to:
本文件使用了[Po11t]中定义的许多术语。对于任何冲突内容，本文件将取代[Po11t]。本文件使用基准方法工作组（BMWG）发布的其他文件中定义的现有术语。示例包括但不限于：
Throughput [Br91], Section 3.17 Offered Load [Ma98], Section 3.5.2 Forwarding Rate [Ma98], Section 3.6.1 Device Under Test (DUT) [Ma98], Section 3.1.1 System Under Test (SUT) [Ma98], Section 3.1.2 Out-of-Order Packet [Po06], Section 3.3.4 Duplicate Packet [Po06], Section 3.3.5 Stream [Po06], Section 3.3.2 Forwarding Delay [Po06], Section 3.2.4 IP Packet Delay Variation (IPDV) [De02], Section 1.2 Loss Period [Ko02], Section 4
吞吐量[Br91]，第3.17节提供负载[Ma98]，第3.5.2节转发速率[Ma98]，第3.6.1节被测设备（DUT）[Ma98]，第3.1.1节被测系统（SUT）[Ma98]，第3.1.2节无序数据包[Po06]，第3.3.4节重复数据包[Po06]，第3.3.5节流[Po06]，第3.3.2节转发延迟[Po06]，第3.2.4节IP数据包延迟变化（IPDV）[De02]，第1.2节丢失周期[Ko02]，第4节
Figure 1 shows the test topology to measure IGP convergence time due to local Convergence Events such as Local Interface failure and recovery (Section 8.1.1), Layer 2 session failure and recovery (Section 8.2.1), and IGP adjacency failure and recovery (Section 8.2.2). This topology is also used to measure IGP convergence time due to route withdrawal and re-advertisement (Section 8.2.3) and to measure IGP convergence time due to route cost change (Section 8.3.2) Convergence Events. IGP adjacencies MUST be established between Tester and DUT: one on the Ingress Interface, one on the Preferred Egress Interface, and one on the Next-Best Egress Interface. For this purpose, the Tester emulates three routers (RTa, RTb, and RTc), each establishing one adjacency with the DUT.
图1显示了测试拓扑，用于测量由于局部收敛事件（如局部接口故障和恢复（第8.1.1节）、第2层会话故障和恢复（第8.2.1节）以及IGP邻接故障和恢复（第8.2.2节））而导致的IGP收敛时间。该拓扑还用于测量因路线撤回和重新公布（第8.2.3节）而导致的IGP收敛时间，以及因路线成本变化（第8.3.2节）收敛事件而导致的IGP收敛时间。必须在测试仪和DUT之间建立IGP邻接：一个在入口接口上，一个在首选出口接口上，另一个在次优出口接口上。为此，测试仪模拟三个路由器（RTa、RTb和RTc），每个路由器与DUT建立一个邻接。
-------
| | Preferred .......
| |------------------. RTb .
....... Ingress | | Egress Interface .......
. RTa .------------| DUT |
....... Interface | | Next-Best .......
| |------------------. RTc .
| | Egress Interface .......
-------
-------
| | Preferred .......
| |------------------. RTb .
....... Ingress | | Egress Interface .......
. RTa .------------| DUT |
....... Interface | | Next-Best .......
| |------------------. RTc .
| | Egress Interface .......
-------
Figure 1: IGP convergence test topology for local changes
图1：局部更改的IGP收敛测试拓扑
Figure 2 shows the test topology to measure IGP convergence time due to local Convergence Events with a non-Equal Cost Multipath (ECMP) Preferred Egress Interface and ECMP Next-Best Egress Interfaces (Section 8.1.1). In this topology, the DUT is configured with each Next-Best Egress Interface as a member of a single ECMP set. The Preferred Egress Interface is not a member of an ECMP set. The Tester emulates N+2 neighbor routers (N>0): one router for the
图2显示了测量IGP收敛时间的测试拓扑，该时间是由具有非等成本多路径（ECMP）首选出口接口和ECMP次优出口接口的局部收敛事件引起的（第8.1.1节）。在这种拓扑结构中，DUT将每个次优出口接口配置为单个ECMP集的成员。首选出口接口不是ECMP集合的成员。测试仪模拟N+2个相邻路由器（N>0）：一个路由器用于
Ingress Interface (RTa), one router for the Preferred Egress Interface (RTb), and N routers for the members of the ECMP set (RTc1...RTcN). IGP adjacencies MUST be established between Tester and DUT: one on the Ingress Interface, one on the Preferred Egress Interface, and one on each member of the ECMP set. When the test specifies to observe the Next-Best Egress Interface statistics, the combined statistics for all ECMP members should be observed.
入口接口（RTa），一个路由器用于首选出口接口（RTb），N个路由器用于ECMP集合的成员（RTc1…RTcN）。必须在测试仪和DUT之间建立IGP邻接：一个在入口接口上，一个在首选出口接口上，一个在ECMP集合的每个成员上。当测试指定观察次优出口接口统计信息时，应观察所有ECMP成员的组合统计信息。
-------
| | Preferred .......
| |------------------. RTb .
| | Egress Interface .......
| |
| | ECMP Set ........
....... Ingress | |------------------. RTc1 .
. RTa .------------| DUT | Interface 1 ........
....... Interface | | .
| | .
| | .
| | ECMP Set ........
| |------------------. RTcN .
| | Interface N ........
-------
-------
| | Preferred .......
| |------------------. RTb .
| | Egress Interface .......
| |
| | ECMP Set ........
....... Ingress | |------------------. RTc1 .
. RTa .------------| DUT | Interface 1 ........
....... Interface | | .
| | .
| | .
| | ECMP Set ........
| |------------------. RTcN .
| | Interface N ........
-------
Figure 2: IGP convergence test topology for local changes with non-ECMP to ECMP convergence
图2：非ECMP到ECMP收敛的局部变化的IGP收敛测试拓扑
Figure 3 shows the test topology to measure IGP convergence time due to Remote Interface failure and recovery (Section 8.1.2). In this topology, the two routers DUT1 and DUT2 are considered the System Under Test (SUT) and SHOULD be identically configured devices of the same model. IGP adjacencies MUST be established between Tester and SUT, one on the Ingress Interface, one on the Preferred Egress Interface, and one on the Next-Best Egress Interface. For this purpose, the Tester emulates three routers (RTa, RTb, and RTc). In this topology, a packet forwarding loop, also known as micro-loop (see [Sh10]), may occur transiently between DUT1 and DUT2 during convergence.
图3显示了测量远程接口故障和恢复引起的IGP收敛时间的测试拓扑（第8.1.2节）。在这种拓扑结构中，两个路由器DUT1和DUT2被视为被测系统（SUT），应该是相同型号的相同配置设备。必须在测试仪和SUT之间建立IGP邻接，一个在入口接口上，一个在首选出口接口上，另一个在次优出口接口上。为此，测试仪模拟三个路由器（RTa、RTb和RTc）。在这种拓扑结构中，数据包转发环路，也称为微环路（参见[Sh10]），在收敛期间可能会在DUT1和DUT2之间瞬时发生。
--------
| | -------- Preferred .......
| |--| DUT2 |------------------. RTb .
....... Ingress | | -------- Egress Interface .......
. RTa .------------| DUT1 |
....... Interface | | Next-Best .......
| |----------------------------. RTc .
| | Egress Interface .......
--------
--------
| | -------- Preferred .......
| |--| DUT2 |------------------. RTb .
....... Ingress | | -------- Egress Interface .......
. RTa .------------| DUT1 |
....... Interface | | Next-Best .......
| |----------------------------. RTc .
| | Egress Interface .......
--------
Figure 3: IGP convergence test topology for remote changes
图3：远程更改的IGP收敛测试拓扑
Figure 4 shows the test topology to measure IGP convergence time due to remote Convergence Events with a non-ECMP Preferred Egress Interface and ECMP Next-Best Egress Interfaces (Section 8.1.2). In this topology the two routers DUT1 and DUT2 are considered System Under Test (SUT) and MUST be identically configured devices of the same model. Router DUT1 is configured with the Next-Best Egress Interface an ECMP set of interfaces. The Preferred Egress Interface of DUT1 is not a member of an ECMP set. The Tester emulates N+2 neighbor routers (N>0), one for the Ingress Interface (RTa), one for DUT2 (RTb) and one for each member of the ECMP set (RTc1...RTcN). IGP adjacencies MUST be established between Tester and SUT, one on each interface of the SUT. For this purpose each of the N+2 routers emulated by the Tester establishes one adjacency with the SUT. In this topology, there is a possibility of a packet-forwarding loop that may occur transiently between DUT1 and DUT2 during convergence (micro-loop, see [Sh10]). When the test specifies to observe the Next-Best Egress Interface statistics, the combined statistics for all members of the ECMP set should be observed.
图4显示了测量IGP收敛时间的测试拓扑，该时间是由于远程收敛事件引起的，具有非ECMP首选出口接口和ECMP次优出口接口（第8.1.2节）。在这种拓扑结构中，两个路由器DUT1和DUT2被视为测试中的系统（SUT），并且必须是相同型号的相同配置设备。路由器DUT1配置有下一个最佳出口接口，即一组ECMP接口。DUT1的首选出口接口不是ECMP集合的成员。测试仪模拟N+2个邻居路由器（N>0），一个用于入口接口（RTa），一个用于DUT2（RTb），一个用于ECMP集的每个成员（RTc1…RTcN）。必须在测试仪和SUT之间建立IGP邻接，SUT的每个接口上各有一个。为此，测试仪模拟的每个N+2路由器与SUT建立一个邻接。在这种拓扑结构中，在收敛过程中，DUT1和DUT2之间可能会出现短暂的包转发环路（微环路，见[Sh10]）。当测试指定观察次优出口接口统计信息时，应观察ECMP集所有成员的组合统计信息。
--------
| | -------- Preferred .......
| |--| DUT2 |------------------. RTb .
| | -------- Egress Interface .......
| |
| | ECMP Set ........
....... Ingress | |----------------------------. RTc1 .
. RTa .------------| DUT1 | Interface 1 ........
....... Interface | | .
| | .
| | .
| | ECMP Set ........
| |----------------------------. RTcN .
| | Interface N ........
--------
--------
| | -------- Preferred .......
| |--| DUT2 |------------------. RTb .
| | -------- Egress Interface .......
| |
| | ECMP Set ........
....... Ingress | |----------------------------. RTc1 .
. RTa .------------| DUT1 | Interface 1 ........
....... Interface | | .
| | .
| | .
| | ECMP Set ........
| |----------------------------. RTcN .
| | Interface N ........
--------
Figure 4: IGP convergence test topology for remote changes with non-ECMP to ECMP convergence
图4：使用非ECMP到ECMP聚合的远程更改的IGP聚合测试拓扑
Figure 5 shows the test topology to measure IGP convergence time due to local Convergence Events of a member of an Equal Cost Multipath (ECMP) set (Section 8.1.3). In this topology, the DUT is configured with each egress interface as a member of a single ECMP set and the Tester emulates N+1 next-hop routers, one for the Ingress Interface (RTa) and one for each member of the ECMP set (RTb1...RTbN). IGP adjacencies MUST be established between Tester and DUT, one on the Ingress Interface and one on each member of the ECMP set. For this purpose, each of the N+1 routers emulated by the Tester establishes one adjacency with the DUT. When the test specifies to observe the Next-Best Egress Interface statistics, the combined statistics for all ECMP members except the one affected by the Convergence Event should be observed.
图5显示了测量因等成本多路径（ECMP）集合成员的局部收敛事件而导致的IGP收敛时间的测试拓扑（第8.1.3节）。在此拓扑中，DUT将每个出口接口配置为单个ECMP集的一个成员，测试仪模拟N+1个下一跳路由器，一个用于入口接口（RTa），另一个用于ECMP集的每个成员（RTb1…RTbN）。必须在测试仪和DUT之间建立IGP邻接，一个在入口接口上，一个在ECMP集合的每个成员上。为此，测试仪模拟的每个N+1路由器与DUT建立一个邻接关系。当测试指定观察次优出口接口统计信息时，应观察所有ECMP成员（受收敛事件影响的成员除外）的组合统计信息。
-------
| | ECMP Set ........
| |-------------. RTb1 .
| | Interface 1 ........
....... Ingress | | .
. RTa .------------| DUT | .
....... Interface | | .
| | ECMP Set ........
| |-------------. RTbN .
| | Interface N ........
-------
-------
| | ECMP Set ........
| |-------------. RTb1 .
| | Interface 1 ........
....... Ingress | | .
. RTa .------------| DUT | .
....... Interface | | .
| | ECMP Set ........
| |-------------. RTbN .
| | Interface N ........
-------
Figure 5: IGP convergence test topology for local ECMP changes
图5：局部ECMP更改的IGP收敛测试拓扑
Figure 6 shows the test topology to measure IGP convergence time due to remote Convergence Events of a member of an Equal Cost Multipath (ECMP) set (Section 8.1.4). In this topology, the two routers DUT1 and DUT2 are considered the System Under Test (SUT) and MUST be identically configured devices of the same model. Router DUT1 is configured with each egress interface as a member of a single ECMP set, and the Tester emulates N+1 neighbor routers (N>0), one for the Ingress Interface (RTa) and one for each member of the ECMP set (RTb1...RTbN). IGP adjacencies MUST be established between Tester and SUT, one on each interface of the SUT. For this purpose, each of the N+1 routers emulated by the Tester establishes one adjacency with the SUT (N-1 emulated routers are adjacent to DUT1 egress interfaces, one emulated router is adjacent to DUT1 Ingress Interface, and one emulated router is adjacent to DUT2). In this topology, there is a possibility of a packet-forwarding loop that may occur transiently between DUT1 and DUT2 during convergence (micro-loop, see [Sh10]). When the test specifies to observe the Next-Best Egress Interface statistics, the combined statistics for all ECMP members except the one affected by the Convergence Event should be observed.
图6显示了测量因等成本多路径（ECMP）集合成员的远程收敛事件而导致的IGP收敛时间的测试拓扑（第8.1.4节）。在这种拓扑结构中，两个路由器DUT1和DUT2被视为被测系统（SUT），并且必须是相同型号的相同配置设备。路由器DUT1将每个出口接口配置为单个ECMP集的一个成员，测试仪模拟N+1个邻居路由器（N>0），一个用于入口接口（RTa），一个用于ECMP集的每个成员（RTb1…RTbN）。必须在测试仪和SUT之间建立IGP邻接，SUT的每个接口上各有一个。为此，测试仪模拟的每个N+1路由器与SUT建立一个邻接（N-1模拟路由器与DUT1出口接口相邻，一个模拟路由器与DUT1入口接口相邻，一个模拟路由器与DUT2相邻）。在这种拓扑结构中，在收敛过程中，DUT1和DUT2之间可能会出现短暂的包转发环路（微环路，见[Sh10]）。当测试指定观察次优出口接口统计信息时，应观察所有ECMP成员（受收敛事件影响的成员除外）的组合统计信息。
--------
| | ECMP Set -------- ........
| |-------------| DUT2 |---. RTb1 .
| | Interface 1 -------- ........
| |
| | ECMP Set ........
....... Ingress | |------------------------. RTb2 .
. RTa .------------| DUT1 | Interface 2 ........
....... Interface | | .
| | .
| | .
| | ECMP Set ........
| |------------------------. RTbN .
| | Interface N ........
--------
--------
| | ECMP Set -------- ........
| |-------------| DUT2 |---. RTb1 .
| | Interface 1 -------- ........
| |
| | ECMP Set ........
....... Ingress | |------------------------. RTb2 .
. RTa .------------| DUT1 | Interface 2 ........
....... Interface | | .
| | .
| | .
| | ECMP Set ........
| |------------------------. RTbN .
| | Interface N ........
--------
Figure 6: IGP convergence test topology for remote ECMP changes
图6：远程ECMP更改的IGP收敛测试拓扑
Figure 7 shows the test topology to measure IGP convergence time due to local Convergence Events with members of a Parallel Link (Section 8.1.5). In this topology, the DUT is configured with each egress interface as a member of a Parallel Link and the Tester emulates two neighbor routers, one for the Ingress Interface (RTa) and one for the Parallel Link members (RTb). IGP adjacencies MUST be
图7显示了测试拓扑，用于测量由于并联链路成员的局部收敛事件而导致的IGP收敛时间（第8.1.5节）。在这种拓扑结构中，DUT将每个出口接口配置为并行链路的一个成员，测试仪模拟两个相邻路由器，一个用于入口接口（RTa），另一个用于并行链路成员（RTb）。IGP邻接必须是
established on the Ingress Interface and on all N members of the Parallel Link between Tester and DUT (N>0). For this purpose, the routers emulated by the Tester establishes N+1 adjacencies with the DUT. When the test specifies to observe the Next-Best Egress Interface statistics, the combined statistics for all Parallel Link members except the one affected by the Convergence Event should be observed.
在入口接口和测试仪与DUT之间并联链路的所有N个成员上建立（N>0）。为此，测试仪模拟的路由器与DUT建立N+1邻接。当测试指定观察次优出口接口统计信息时，应观察除受收敛事件影响的并行链路成员外的所有并行链路成员的组合统计信息。
------- .......
| | Parallel Link . .
| |----------------. .
| | Interface 1 . .
....... Ingress | | . . .
. RTa .------------| DUT | . . RTb .
....... Interface | | . . .
| | Parallel Link . .
| |----------------. .
| | Interface N . .
------- .......
------- .......
| | Parallel Link . .
| |----------------. .
| | Interface 1 . .
....... Ingress | | . . .
. RTa .------------| DUT | . . RTb .
....... Interface | | . . .
| | Parallel Link . .
| |----------------. .
| | Interface N . .
------- .......
Figure 7: IGP convergence test topology for Parallel Link changes
图7：并行链路更改的IGP收敛测试拓扑
Two concepts will be highlighted in this section: convergence time and loss of connectivity period.
本节将重点介绍两个概念：收敛时间和连通性丧失期。
The Route Convergence [Po11t] time indicates the period in time between the Convergence Event Instant [Po11t] and the instant in time the DUT is ready to forward traffic for a specific route on its Next-Best Egress Interface and maintains this state for the duration of the Sustained Convergence Validation Time [Po11t]. To measure Route Convergence time, the Convergence Event Instant and the traffic received from the Next-Best Egress Interface need to be observed.
路由会聚[Po11t]时间表示会聚事件瞬间[Po11t]和DUT准备在其下一个最佳出口接口上转发特定路由的流量的瞬间之间的时间段，并在持续会聚验证时间[Po11t]的持续时间内保持该状态。为了测量路线会聚时间，需要观察会聚事件瞬间和从次优出口接口接收的流量。
The Route Loss of Connectivity Period [Po11t] indicates the time during which traffic to a specific route is lost following a Convergence Event until Full Convergence [Po11t] completes. This Route Loss of Connectivity Period can consist of one or more Loss Periods [Ko02]. For the test cases described in this document, it is expected to have a single Loss Period. To measure the Route Loss of Connectivity Period, the traffic received from the Preferred Egress Interface and the traffic received from the Next-Best Egress Interface need to be observed.
Route Loss of Connectivity Period[Po11t]表示在汇聚事件发生后特定路由的流量丢失直至完全汇聚[Po11t]完成的时间。此路由连接丢失周期可由一个或多个丢失周期组成[Ko02]。对于本文档中描述的测试用例，预计将有一个单一的损失期。为了测量连接周期的路由损失，需要观察从首选出口接口接收的流量和从次优出口接口接收的流量。
The Route Loss of Connectivity Period is most important since that has a direct impact on the network user's application performance.
路由连接丢失周期是最重要的，因为它直接影响网络用户的应用程序性能。
In general, the Route Convergence time is larger than or equal to the Route Loss of Connectivity Period. Depending on which Convergence Event occurs and how this Convergence Event is applied, traffic for a route may still be forwarded over the Preferred Egress Interface after the Convergence Event Instant, before converging to the Next-Best Egress Interface. In that case, the Route Loss of Connectivity Period is shorter than the Route Convergence time.
一般情况下，路由收敛时间大于或等于路由连通性丢失周期。根据发生的汇聚事件以及该汇聚事件的应用方式，在汇聚事件瞬间之后，在汇聚到下一个最佳出口接口之前，路由的业务仍然可以通过优选出口接口转发。在这种情况下，路由连通性丢失周期比路由收敛时间短。
At least one condition needs to be fulfilled for Route Convergence time to be equal to Route Loss of Connectivity Period. The condition is that the Convergence Event causes an instantaneous traffic loss for the measured route. A fiber cut on the Preferred Egress Interface is an example of such a Convergence Event.
至少需要满足一个条件，使路由收敛时间等于路由连接丢失周期。条件是收敛事件会导致测量路线的瞬时交通损失。优选出口接口上的光纤切割就是此类会聚事件的一个例子。
A second condition applies to Route Convergence time measurements based on Connectivity Packet Loss [Po11t]. This second condition is that there is only a single Loss Period during Route Convergence. For the test cases described in this document, the second condition is expected to apply.
第二个条件适用于基于连接性分组丢失的路由收敛时间测量[Po11t]。第二个条件是，在路由收敛期间只有一个损失周期。对于本文档中描述的测试用例，第二个条件预计适用。
To measure convergence time benchmarks for Convergence Events caused by a Tester, such as an IGP cost change, the Tester MAY start to discard all traffic received from the Preferred Egress Interface at the Convergence Event Instant, or MAY separately observe packets received from the Preferred Egress Interface prior to the Convergence Event Instant. This way, these Convergence Events can be treated the same as Convergence Events that cause instantaneous traffic loss.
为了测量由测试仪引起的收敛事件（如IGP成本变化）的收敛时间基准，测试仪可在收敛事件瞬间开始丢弃从首选出口接口接收的所有通信量，或者可以在汇聚事件瞬间之前单独观察从优选出口接口接收的分组。这样，这些汇聚事件可以被视为导致瞬时流量损失的汇聚事件。
To measure convergence time benchmarks without instantaneous traffic loss (either real or induced by the Tester) at the Convergence Event Instant, such as a reversion of a link failure Convergence Event, the Tester SHALL only observe packet statistics on the Next-Best Egress Interface. If using the Rate-Derived method to benchmark convergence times for such Convergence Events, the Tester MUST collect a timestamp at the Convergence Event Instant. If using a loss-derived method to benchmark convergence times for such Convergence Events, the Tester MUST measure the period in time between the Start Traffic Instant and the Convergence Event Instant. To measure this period in time, the Tester can collect timestamps at the Start Traffic Instant and the Convergence Event Instant.
为了在聚合事件瞬间（如链路故障聚合事件的恢复）测量聚合时间基准，而不造成瞬时流量损失（测试仪实际或诱发），测试仪应仅观察次优出口接口上的数据包统计。如果使用速率导出的方法对此类收敛事件的收敛时间进行基准测试，测试人员必须在收敛事件瞬间收集时间戳。如果使用损失衍生方法对此类收敛事件的收敛时间进行基准测试，测试人员必须测量开始流量瞬间和收敛事件瞬间之间的时间段。为了测量这段时间，测试仪可以在开始流量瞬间和汇聚事件瞬间收集时间戳。
The Convergence Event Instant together with the receive rate observations on the Next-Best Egress Interface allow the derivation of the convergence time benchmarks using the Rate-Derived Method [Po11t].
收敛事件瞬间以及下一个最佳出口界面上的接收速率观测值允许使用速率导出方法推导收敛时间基准[Po11t]。
By observing packets on the Next-Best Egress Interface only, the observed Impaired Packet count is the number of Impaired Packets between Traffic Start Instant and Convergence Recovery Instant. To measure convergence times using a loss-derived method, the Impaired Packet count between the Convergence Event Instant and the Convergence Recovery Instant is needed. The time between Traffic Start Instant and Convergence Event Instant must be accounted for. An example may clarify this.
通过仅在下一个最佳出口接口上观察数据包，观察到的受损数据包计数是流量开始瞬间和收敛恢复瞬间之间受损数据包的数量。为了使用丢失衍生方法测量收敛时间，需要收敛事件瞬间和收敛恢复瞬间之间的受损数据包计数。必须考虑流量开始瞬间和汇聚事件瞬间之间的时间。举个例子可以说明这一点。
Figure 8 illustrates a Convergence Event without instantaneous traffic loss for all routes. The top graph shows the Forwarding Rate over all routes, the bottom graph shows the Forwarding Rate for a single route Rta. Some time after the Convergence Event Instant, the Forwarding Rate observed on the Preferred Egress Interface starts to decrease. In the example, route Rta is the first route to experience packet loss at time Ta. Some time later, the Forwarding Rate observed on the Next-Best Egress Interface starts to increase. In the example, route Rta is the first route to complete convergence at time Ta'.
图8显示了一个收敛事件，所有路线都没有瞬时流量损失。上图显示所有路由的转发速率，下图显示单个路由Rta的转发速率。在收敛事件瞬间之后的一段时间，在首选出口接口上观察到的转发速率开始降低。在该示例中，路由Rta是在时间Ta处经历分组丢失的第一个路由。一段时间后，在下一个最佳出口接口上观察到的转发速率开始增加。在该示例中，路由Rta是在时间Ta'处完成收敛的第一条路由。
^
Fwd |
Rate |------------- ............
| \ .
| \ .
| \ .
| \ .
|.................-.-.-.-.-.-.----------------
+----+-------+---------------+----------------->
^ ^ ^ ^ time
T0 CEI Ta Ta'
^
Fwd |
Rate |------------- ............
| \ .
| \ .
| \ .
| \ .
|.................-.-.-.-.-.-.----------------
+----+-------+---------------+----------------->
^ ^ ^ ^ time
T0 CEI Ta Ta'
^
Fwd |
Rate |------------- .................
Rta | | .
| | .
|.............-.-.-.-.-.-.-.-.----------------
+----+-------+---------------+----------------->
^ ^ ^ ^ time
T0 CEI Ta Ta'
^
Fwd |
Rate |------------- .................
Rta | | .
| | .
|.............-.-.-.-.-.-.-.-.----------------
+----+-------+---------------+----------------->
^ ^ ^ ^ time
T0 CEI Ta Ta'
Preferred Egress Interface: ---
Next-Best Egress Interface: ...
Preferred Egress Interface: ---
Next-Best Egress Interface: ...
T0 : Start Traffic Instant CEI : Convergence Event Instant Ta : the time instant packet loss for route Rta starts Ta' : the time instant packet impairment for route Rta ends
T0：开始流量瞬间CEI：汇聚事件瞬间Ta：路由Rta的瞬间丢包开始Ta的时间”：路由Rta的瞬间丢包结束的时间
Figure 8
图8
If only packets received on the Next-Best Egress Interface are observed, the duration of the loss period for route Rta can be calculated from the received packets as in Equation 1. Since the Convergence Event Instant is the start time for convergence time measurement, the period in time between T0 and CEI needs to be subtracted from the calculated result to become the convergence time, as in Equation 2.
如果仅观察到在下一最佳出口接口上接收的分组，则路由Rta的丢失周期的持续时间可根据接收的分组计算，如等式1所示。由于收敛事件瞬间是收敛时间测量的开始时间，因此需要从计算结果中减去T0和CEI之间的时间段，以成为收敛时间，如等式2所示。
Next-Best Egress Interface loss period
= (packets transmitted
- packets received from Next-Best Egress Interface) / tx rate
= Ta' - T0
Next-Best Egress Interface loss period
= (packets transmitted
- packets received from Next-Best Egress Interface) / tx rate
= Ta' - T0
Equation 1
方程式1
convergence time
= Next-Best Egress Interface loss period - (CEI - T0)
= Ta' - CEI
convergence time
= Next-Best Egress Interface loss period - (CEI - T0)
= Ta' - CEI
Equation 2
方程式2
Route Loss of Connectivity Period SHOULD be measured using the Route-Specific Loss-Derived Method. Since the start instant and end instant of the Route Loss of Connectivity Period can be different for each route, these cannot be accurately derived by only observing global statistics over all routes. An example may clarify this.
应使用特定于路线的损失导出方法测量连接期间的路线损失。由于每条路由的连接丢失周期的开始时刻和结束时刻可能不同，因此仅通过观察所有路由的全局统计信息无法准确得出这些时刻。举个例子可以说明这一点。
Following a Convergence Event, route Rta is the first route for which packet impairment starts; the Route Loss of Connectivity Period for route Rta starts at time Ta. Route Rtb is the last route for which packet impairment starts; the Route Loss of Connectivity Period for route Rtb starts at time Tb with Tb>Ta.
在会聚事件之后，路由Rta是分组损伤开始的第一个路由；路由Rta的路由连接丢失周期从时间Ta开始。路由Rtb是数据包损坏开始的最后一条路由；路由Rtb的路由连接丢失周期从时间Tb开始，Tb>Ta。
^
Fwd |
Rate |-------- -----------
| \ /
| \ /
| \ /
| \ /
| ---------------
+------------------------------------------>
^ ^ ^ ^ time
Ta Tb Ta' Tb'
Tb'' Ta''
^
Fwd |
Rate |-------- -----------
| \ /
| \ /
| \ /
| \ /
| ---------------
+------------------------------------------>
^ ^ ^ ^ time
Ta Tb Ta' Tb'
Tb'' Ta''
Figure 9: Example Route Loss Of Connectivity Period
图9：连接期间的路由丢失示例
If the DUT implementation were such that route Rta would be the first route for which traffic loss ends at time Ta' (with Ta'>Tb), and route Rtb would be the last route for which traffic loss ends at time Tb' (with Tb'>Ta'). By only observing global traffic statistics over all routes, the minimum Route Loss of Connectivity Period would be measured as Ta'-Ta. The maximum calculated Route Loss of Connectivity Period would be Tb'-Ta. The real minimum and maximum Route Loss of Connectivity Periods are Ta'-Ta and Tb'-Tb. Illustrating this with the numbers Ta=0, Tb=1, Ta'=3, and Tb'=5 would give a Loss of Connectivity Period between 3 and 5 derived from the global traffic statistics, versus the real Loss of Connectivity Period between 3 and 4.
如果DUT的实现是这样的，那么路由Rta将是在时间Ta'（带Tb'>Tb）流量损失结束的第一条路由，而路由Rtb将是在时间Tb'（带Tb'>Ta'）流量损失结束的最后一条路由。通过仅观察所有路线的全球交通统计数据，最小路线连通性损失周期将被测量为Ta'-Ta。计算得出的连接期最大路由损失为Tb'-Ta。连接期间的实际最小和最大路由损失为Ta'-Ta和Tb'-Tb。用数字Ta=0、Tb=1、Ta'=3和Tb'=5来说明这一点将给出从全球流量统计数据得出的3到5之间的连接丢失周期，而实际连接丢失周期为3到4之间。
If the DUT implementation were such that route Rtb would be the first for which packet loss ends at time Tb'' and route Rta would be the last for which packet impairment ends at time Ta'', then the minimum and maximum Route Loss of Connectivity Periods derived by observing only global traffic statistics would be Tb''-Ta and Ta''-Ta. The real minimum and maximum Route Loss of Connectivity Periods are Tb''-Tb and Ta''-Ta. Illustrating this with the numbers Ta=0, Tb=1, Ta''=5, Tb''=3 would give a Loss of Connectivity Period between 3 and 5 derived from the global traffic statistics, versus the real Loss of Connectivity Period between 2 and 5.
如果DUT实现是这样的，即路由Rtb将是在时间Tb''结束分组丢失的第一个路由，而路由Rta将是在时间Ta''结束分组损坏的最后一个路由，则通过仅观察全局流量统计数据得出的连接周期的最小和最大路由丢失将是Tb'-Ta和Ta'-Ta。实际的最小和最大路由连接丢失周期为Tb'-Tb和Ta'-Ta。用数字Ta=0、Tb=1、Ta'=5、Tb'=3来说明这一点，将给出从全局流量统计数据得出的3到5之间的连接丢失周期，而实际连接丢失周期为2到5之间。
The two implementation variations in the above example would result in the same derived minimum and maximum Route Loss of Connectivity Periods when only observing the global packet statistics, while the real Route Loss of Connectivity Periods are different.
当仅观察全局分组统计时，上述示例中的两个实现变化将导致相同的导出的最小和最大连接周期路由丢失，而连接周期的实际路由丢失是不同的。
The test cases described in Section 8 can be used for link-state IGPs, such as IS-IS or OSPF. The IGP convergence time test methodology is identical.
第8节中描述的测试用例可用于链路状态IGP，如IS-IS或OSPF。IGP收敛时间测试方法相同。
The obtained results for IGP convergence time may vary if other routing protocols are enabled and routes learned via those protocols are installed. IGP convergence times SHOULD be benchmarked without routes installed from other protocols. Any enabled IGP routing protocol extension (such as extensions for Traffic Engineering) and any enabled IGP routing protocol security mechanism must be reported with the results.
如果启用其他路由协议并安装通过这些协议学习的路由，则获得的IGP收敛时间结果可能会有所不同。IGP收敛时间应在不安装其他协议路由的情况下进行基准测试。任何启用的IGP路由协议扩展（如流量工程扩展）和任何启用的IGP路由协议安全机制都必须报告结果。
The Tester emulates a single IGP topology. The DUT establishes IGP adjacencies with one or more of the emulated routers in this single IGP topology emulated by the Tester. See test topology details in Section 3. The emulated topology SHOULD only be advertised on the DUT egress interfaces.
测试仪模拟单个IGP拓扑。DUT在测试仪模拟的单个IGP拓扑中与一个或多个模拟路由器建立IGP邻接。请参阅第3节中的测试拓扑详细信息。仿真拓扑应仅在DUT出口接口上公布。
The number of IGP routes and number of nodes in the topology, and the type of topology will impact the measured IGP convergence time. To obtain results similar to those that would be observed in an operational network, it is RECOMMENDED that the number of installed routes and nodes closely approximate that of the network (e.g., thousands of routes with tens or hundreds of nodes).
拓扑中的IGP路由数和节点数以及拓扑类型将影响测量的IGP收敛时间。为了获得与在运行网络中观察到的结果类似的结果，建议安装的路由和节点的数量与网络的数量接近（例如，数千条路由，数十个或数百个节点）。
The number of areas (for OSPF) and levels (for IS-IS) can impact the benchmark results.
区域数量（OSPF）和级别（IS-IS）会影响基准结果。
There are timers that may impact the measured IGP convergence times. The benchmark metrics MAY be measured at any fixed values for these timers. To obtain results similar to those that would be observed in an operational network, it is RECOMMENDED to configure the timers with the values as configured in the operational network.
存在可能影响测量IGP收敛时间的计时器。基准度量可以在这些计时器的任何固定值上进行测量。为了获得类似于在运行网络中观察到的结果，建议使用在运行网络中配置的值配置计时器。
Examples of timers that may impact measured IGP convergence time include, but are not limited to:
可能影响测量IGP收敛时间的计时器示例包括但不限于：
Interface failure indication
接口故障指示
IGP hello timer
你好定时器
IGP dead-interval or hold-timer
IGP死区间隔或保持计时器
Link State Advertisement (LSA) or Link State Packet (LSP) generation delay
链路状态播发（LSA）或链路状态包（LSP）生成延迟
LSA or LSP flood packet pacing
LSA或LSP泛洪数据包调整
Route calculation delay
路由计算延迟
All test cases in this methodology document can be executed with any interface type. The type of media may dictate which test cases may be executed. Each interface type has a unique mechanism for detecting link failures, and the speed at which that mechanism operates will influence the measurement results. All interfaces MUST be the same media and Throughput [Br91][Br99] for each test case. All interfaces SHOULD be configured as point-to-point.
本方法文档中的所有测试用例都可以使用任何接口类型执行。介质的类型可能决定可以执行哪些测试用例。每种接口类型都有一种独特的检测链路故障的机制，该机制的运行速度将影响测量结果。对于每个测试用例，所有接口必须是相同的介质和吞吐量[Br91][Br99]。所有接口都应配置为点对点。
The Throughput of the device, as defined in [Br91] and benchmarked in [Br99] at a fixed packet size, needs to be determined over the preferred path and over the next-best path. The Offered Load SHOULD be the minimum of the measured Throughput of the device over the primary path and over the backup path. The packet size is selectable and MUST be recorded. Packet size is measured in bytes and includes the IP header and payload.
如[Br91]中所定义并在[Br99]中以固定数据包大小为基准的设备吞吐量，需要在首选路径和下一个最佳路径上确定。提供的负载应为设备在主路径和备份路径上的最小测量吞吐量。数据包大小是可选择的，必须记录。数据包大小以字节为单位，包括IP报头和有效负载。
The destination addresses for the Offered Load MUST be distributed such that all routes or a statistically representative subset of all routes are matched and each of these routes is offered an equal share of the Offered Load. It is RECOMMENDED to send traffic matching all routes, but a statistically representative subset of all routes can be used if required.
所提供负载的目的地地址必须进行分配，以便所有路由或所有路由的统计代表子集都匹配，并且这些路由中的每一个路由都提供了所提供负载的相等份额。建议发送匹配所有路由的流量，但如果需要，可以使用所有路由的统计代表子集。
Splitting traffic flows across multiple paths (as with ECMP or Parallel Link sets) is in general done by hashing on various fields on the IP or contained headers. The hashing is typically based on the IP source and destination addresses, the protocol ID, and higher-layer flow-dependent fields such as TCP/UDP ports. In practice, within a network core, the hashing is based mainly or exclusively on the IP source and destination addresses. Knowledge of the hashing algorithm used by the DUT is not always possible beforehand and would violate the black-box spirit of this document. Therefore, it is RECOMMENDED to use a randomly distributed range of source and destination IP addresses, protocol IDs, and higher-layer flow-dependent fields for the packets of the Offered Load (see also [Ne07]). The content of the Offered Load MUST remain the same during the test. It is RECOMMENDED to repeat a test multiple times with different random ranges of the header fields such that convergence time benchmarks are measured for different distributions of traffic over the available paths.
通常，通过对IP或包含的报头上的各个字段进行散列，跨多条路径（如ECMP或并行链接集）拆分流量。散列通常基于IP源和目标地址、协议ID和更高层的流相关字段（如TCP/UDP端口）。实际上，在网络核心内，哈希主要或完全基于IP源地址和目标地址。DUT所使用的哈希算法的知识并不总是事先可能的，这将违反本文档的黑箱精神。因此，建议对所提供负载的数据包使用随机分布的源和目标IP地址、协议ID和更高层的流相关字段（另请参见[Ne07]）。在试验过程中，所提供荷载的内容必须保持不变。建议使用不同随机范围的报头字段重复多次测试，以便在可用路径上测量不同流量分布的收敛时间基准。
In the Remote Interface failure test cases using topologies 3, 4, and 6, there is a possibility of a packet-forwarding loop that may occur transiently between DUT1 and DUT2 during convergence (micro-loop, see [Sh10]). The Time To Live (TTL) or Hop Limit value of the packets sent by the Tester may influence the benchmark measurements since it determines which device in the topology may send an ICMP Time Exceeded Message for looped packets.
在使用拓扑3、4和6的远程接口故障测试用例中，在聚合过程中，DUT1和DUT2之间可能会瞬时出现数据包转发环路（微环路，见[Sh10]）。测试仪发送的数据包的生存时间（TTL）或跃点限制值可能会影响基准测量，因为它确定拓扑中的哪个设备可能会发送循环数据包的ICMP超时消息。
The duration of the Offered Load MUST be greater than the convergence time plus the Sustained Convergence Validation Time.
提供负载的持续时间必须大于收敛时间加上持续收敛验证时间。
Offered load should send a packet to each destination before sending another packet to the same destination. It is RECOMMENDED that the packets be transmitted in a round-robin fashion with a uniform interpacket delay.
提供的负载应先向每个目的地发送一个数据包，然后再向同一目的地发送另一个数据包。建议以具有统一分组间延迟的循环方式传输分组。
Since Impaired Packet count is observed to measure the Route Convergence Time, the time between two successive packets offered to each individual route is the highest possible accuracy of any Impaired-Packet-based measurement. The higher the traffic rate offered to each route, the higher the possible measurement accuracy.
由于观察受损分组计数来测量路由收敛时间，因此提供给每个单独路由的两个连续分组之间的时间是任何基于受损分组的测量的最高可能精度。提供给每条路线的交通率越高，可能的测量精度越高。
Also see Section 6 for method-specific measurement accuracy.
具体方法的测量精度也见第6节。
The benchmark measurements may vary for each trial, due to the statistical nature of timer expirations, CPU scheduling, etc. Evaluation of the test data must be done with an understanding of generally accepted testing practices regarding repeatability, variance, and statistical significance of a small number of trials.
由于计时器过期、CPU调度等的统计性质，每个试验的基准测量值可能会有所不同。必须在了解关于少量试验的重复性、差异和统计显著性的公认试验实践的情况下，对试验数据进行评估。
It is RECOMMENDED that the Tester used to execute each test case have the following capabilities:
建议用于执行每个测试用例的测试仪具有以下功能：
1. Ability to establish IGP adjacencies and advertise a single IGP topology to one or more peers.
1. 能够建立IGP邻接并向一个或多个对等方公布单个IGP拓扑。
2. Ability to measure Forwarding Delay, Duplicate Packets, and Out-of-Order Packets.
2. 能够测量转发延迟、重复数据包和无序数据包。
3. An internal time clock to control timestamping, time measurements, and time calculations.
3. 控制时间戳、时间测量和时间计算的内部时钟。
4. Ability to distinguish traffic load received on the Preferred and Next-Best Interfaces [Po11t].
4. 能够区分在首选和次优接口上接收的流量负载[Po11t]。
5. Ability to disable or tune specific Layer 2 and Layer 3 protocol functions on any interface(s).
5. 能够在任何接口上禁用或调整特定的第2层和第3层协议功能。
The Tester MAY be capable of making non-data-plane convergence observations and using those observations for measurements. The Tester MAY be capable of sending and receiving multiple traffic Streams [Po06].
测试仪可能能够进行非数据平面收敛观测，并将这些观测用于测量。测试仪可能能够发送和接收多个业务流[Po06]。
Also see Section 6 for method-specific capabilities.
有关特定于方法的功能，请参见第6节。
Different convergence time benchmark methods MAY be used to measure convergence time benchmark metrics. The Tester capabilities are important criteria to select a specific convergence time benchmark method. The criteria to select a specific benchmark method include, but are not limited to:
可以使用不同的收敛时间基准方法来度量收敛时间基准度量。测试人员的能力是选择特定收敛时间基准方法的重要标准。选择特定基准方法的标准包括但不限于：
Tester capabilities: Sampling Interval, number of Stream statistics to collect Measurement accuracy: Sampling Interval, Offered Load, number of routes Test specification: number of routes DUT capabilities: Throughput, IP Packet Delay Variation
测试仪功能：采样间隔、收集测量精度的流统计数：采样间隔、提供的负载、路由数测试规范：路由数DUT功能：吞吐量、IP数据包延迟变化
To enable collecting statistics of Out-of-Order Packets per flow (see [Th00], Section 3), the Offered Load SHOULD consist of multiple Streams [Po06], and each Stream SHOULD consist of a single flow. If sending multiple Streams, the measured traffic statistics for all Streams MUST be added together.
为了能够收集每个流的无序数据包的统计信息（参见[Th00]，第3节），提供的负载应包括多个流[Po06]，每个流应包括一个流。如果发送多个流，则必须将所有流的测量流量统计数据相加。
In order to verify Full Convergence completion and the Sustained Convergence Validation Time, the Tester MUST measure Forwarding Rate each Packet Sampling Interval.
为了验证完全收敛完成和持续收敛验证时间，测试人员必须测量每个数据包采样间隔的转发速率。
The total number of Impaired Packets between the start of the traffic and the end of the Sustained Convergence Validation Time is used to calculate the Loss-Derived Convergence Time.
从流量开始到持续收敛验证时间结束之间受损数据包的总数用于计算由丢失导出的收敛时间。
The Loss-Derived Method can be used to measure the Loss-Derived Convergence Time, which is the average convergence time over all routes, and to measure the Loss-Derived Loss of Connectivity Period, which is the average Route Loss of Connectivity Period over all routes.
损失衍生方法可用于测量损失衍生收敛时间，即所有路由的平均收敛时间，以及测量损失衍生连通性损失周期，即所有路由的平均连通性损失周期。
The actual value falls within the accuracy interval [-(number of destinations/Offered Load), +(number of destinations/Offered Load)] around the value as measured using the Loss-Derived Method.
实际值在使用损耗导出法测量的值周围的精度区间[-（目的地数量/提供的负载）+（目的地数量/提供的负载）]内。
To enable collecting statistics of Out-of-Order Packets per flow (see [Th00], Section 3), the Offered Load SHOULD consist of multiple Streams [Po06], and each Stream SHOULD consist of a single flow. If sending multiple Streams, the measured traffic statistics for all Streams MUST be added together.
为了能够收集每个流的无序数据包的统计信息（参见[Th00]，第3节），提供的负载应包括多个流[Po06]，每个流应包括一个流。如果发送多个流，则必须将所有流的测量流量统计数据相加。
The Tester measures Forwarding Rate each Sampling Interval. The Packet Sampling Interval influences the observation of the different convergence time instants. If the Packet Sampling Interval is large compared to the time between the convergence time instants, then the different time instants may not be easily identifiable from the Forwarding Rate observation. The presence of IP Packet Delay Variation (IPDV) [De02] may cause fluctuations of the Forwarding Rate observation and can prevent correct observation of the different convergence time instants.
测试仪测量每个采样间隔的转发速率。数据包采样间隔影响不同收敛时刻的观测。如果与收敛时间瞬间之间的时间相比，分组采样间隔较大，则不同的时间瞬间可能不容易从转发速率观测中识别。IP分组延迟变化（IPDV）[De02]的存在可能导致转发速率观测的波动，并且可能阻止对不同收敛时刻的正确观测。
The Packet Sampling Interval MUST be larger than or equal to the time between two consecutive packets to the same destination. For maximum accuracy, the value for the Packet Sampling Interval SHOULD be as small as possible, but the presence of IPDV may require the use of a larger Packet Sampling Interval. The Packet Sampling Interval MUST be reported.
数据包采样间隔必须大于或等于两个连续数据包到同一目的地之间的时间。为了获得最大精度，数据包采样间隔的值应尽可能小，但IPDV的存在可能需要使用更大的数据包采样间隔。必须报告数据包采样间隔。
IPDV causes fluctuations in the number of received packets during each Packet Sampling Interval. To account for the presence of IPDV in determining if a convergence instant has been reached, Forwarding Delay SHOULD be observed during each Packet Sampling Interval. The minimum and maximum number of packets expected in a Packet Sampling Interval in presence of IPDV can be calculated with Equation 3.
IPDV在每个数据包采样间隔期间引起接收数据包数量的波动。为了说明IPDV在确定是否已达到收敛时刻时的存在，应在每个数据包采样间隔期间观察转发延迟。在存在IPDV的情况下，在分组采样间隔中预期的分组的最小和最大数目可以用等式3计算。
number of packets expected in a Packet Sampling Interval in presence of IP Packet Delay Variation = expected number of packets without IP Packet Delay Variation +/-( (maxDelay - minDelay) * Offered Load) where minDelay and maxDelay indicate (respectively) the minimum and maximum Forwarding Delay of packets received during the Packet Sampling Interval
在存在IP数据包延迟变化的情况下，数据包采样间隔内预期的数据包数量=不存在IP数据包延迟变化的预期数据包数量+/-（（maxDelay-minDelay）*提供的负载），其中minDelay和maxDelay分别表示在数据包采样间隔期间接收的数据包的最小和最大转发延迟
Equation 3
方程式3
To determine if a convergence instant has been reached, the number of packets received in a Packet Sampling Interval is compared with the range of expected number of packets calculated in Equation 3.
为了确定是否已经达到收敛时刻，将分组采样间隔中接收的分组数量与等式3中计算的分组的预期数量的范围进行比较。
The Rate-Derived Method SHOULD be used to measure First Route Convergence Time and Full Convergence Time. It SHOULD NOT be used to measure Loss of Connectivity Period (see Section 4).
应使用速率导出法测量第一路径收敛时间和完全收敛时间。它不应用于测量连接中断时间（见第4节）。
The measurement accuracy interval of the Rate-Derived Method depends on the metric being measured or calculated and the characteristics of the related transition. IP Packet Delay Variation (IPDV) [De02] adds uncertainty to the amount of packets received in a Packet Sampling Interval, and this uncertainty adds to the measurement error. The effect of IPDV is not accounted for in the calculation of the accuracy intervals below. IPDV is of importance for the convergence instants where a variation in Forwarding Rate needs to be observed. This is applicable to the Convergence Recovery Instant for all topologies, and for topologies with ECMP it also applies to the Convergence Event Instant and the First Route Convergence Instant. and for topologies with ECMP also Convergence Event Instant and First Route Convergence Instant).
速率导出方法的测量精度区间取决于测量或计算的度量以及相关转换的特征。IP数据包延迟变化（IPDV）[De02]增加了数据包采样间隔内接收的数据包数量的不确定性，该不确定性增加了测量误差。在计算以下精度区间时，未考虑IPDV的影响。IPDV对于需要观察转发速率变化的收敛时刻非常重要。这适用于所有拓扑的收敛恢复瞬间，对于具有ECMP的拓扑，它也适用于收敛事件瞬间和第一路由收敛瞬间。对于具有ECMP的拓扑，还包括收敛事件瞬间和第一路由收敛瞬间）。
If the Convergence Event Instant is observed on the data plane using the Rate Derived Method, it needs to be instantaneous for all routes (see Section 4.1). The actual value of the Convergence Event Instant falls within the accuracy interval [-(Packet Sampling Interval + 1/Offered Load), +0] around the value as measured using the Rate-Derived Method.
如果使用速率导出方法在数据平面上观察到收敛事件瞬间，则所有路线的收敛事件瞬间都必须是瞬时的（见第4.1节）。收敛事件瞬间的实际值在精度区间[-（数据包采样区间+1/提供负载），+0]内，该区间与使用速率导出方法测量的值一致。
If the Convergence Recovery Transition is non-instantaneous for all routes, then the actual value of the First Route Convergence Instant falls within the accuracy interval [-(Packet Sampling Interval + time between two consecutive packets to the same destination), +0] around the value as measured using the Rate-Derived Method, and the actual value of the Convergence Recovery Instant falls within the accuracy interval [-(2 * Packet Sampling Interval), -(Packet Sampling Interval - time between two consecutive packets to the same destination)] around the value as measured using the Rate-Derived Method.
如果收敛恢复过渡对于所有路由而言都是非瞬时的，则第一路由收敛瞬间的实际值在精度间隔[-（数据包采样间隔+两个连续数据包到同一目的地之间的时间），+0]内，该准确间隔围绕使用速率导出方法测得的值，并且收敛恢复瞬间的实际值落在使用速率导出方法测量的值周围的精度间隔[-（2*分组采样间隔），-（分组采样间隔-两个连续分组到同一目的地之间的时间）]内。
The term "time between two consecutive packets to the same destination" is added in the above accuracy intervals since packets are sent in a particular order to all destinations in a stream, and when part of the routes experience packet loss, it is unknown where in the transmit cycle packets to these routes are sent. This uncertainty adds to the error.
术语“到同一目的地的两个连续分组之间的时间”被添加到上述精度间隔中，因为分组以特定顺序发送到流中的所有目的地，并且当部分路由经历分组丢失时，不知道发送到这些路由的分组在发送周期中的何处。这种不确定性增加了误差。
The accuracy intervals of the derived metrics First Route Convergence Time and Rate-Derived Convergence Time are calculated from the above convergence instants accuracy intervals. The actual value of First Route Convergence Time falls within the accuracy interval [-(Packet Sampling Interval + time between two consecutive packets to the same destination), +(Packet Sampling Interval + 1/Offered Load)] around the calculated value. The actual value of Rate-Derived Convergence Time falls within the accuracy interval [-(2 * Packet Sampling Interval), +(time between two consecutive packets to the same destination + 1/Offered Load)] around the calculated value.
从上述收敛时刻的精度区间计算导出的度量的第一路径收敛时间和速率导出的收敛时间的精度区间。第一路由收敛时间的实际值落在计算值周围的精度间隔[-（数据包采样间隔+两个连续数据包到同一目的地之间的时间），+（数据包采样间隔+1/提供负载）]内。速率导出的收敛时间的实际值落在计算值周围的精度间隔[-（2*数据包采样间隔），+（两个连续数据包到同一目的地之间的时间+1/提供负载）]内。
The Offered Load consists of multiple Streams. The Tester MUST measure Impaired Packet count for each Stream separately.
提供的负载由多个流组成。测试仪必须分别测量每个流的受损数据包计数。
In order to verify Full Convergence completion and the Sustained Convergence Validation Time, the Tester MUST measure Forwarding Rate each Packet Sampling Interval. This measurement at each Packet Sampling Interval MAY be per Stream.
为了验证完全收敛完成和持续收敛验证时间，测试人员必须测量每个数据包采样间隔的转发速率。每个分组采样间隔处的该测量可以是每个流。
Only the total number of Impaired Packets measured per Stream at the end of the Sustained Convergence Validation Time is used to calculate the benchmark metrics with this method.
在持续收敛验证时间结束时，仅使用每个流测量的受损数据包总数来计算该方法的基准度量。
The Route-Specific Loss-Derived Method SHOULD be used to measure Route-Specific Convergence Times. It is the RECOMMENDED method to measure Route Loss of Connectivity Period.
应使用特定于路线的损耗推导方法来测量特定于路线的收敛时间。建议使用此方法测量连接期间的路由损失。
Under the conditions explained in Section 4, First Route Convergence Time and Full Convergence Time, as benchmarked using Rate-Derived Method, may be equal to the minimum and maximum (respectively) of the Route-Specific Convergence Times.
在第4节中解释的条件下，第一条路线的收敛时间和完全收敛时间（使用速率导出法进行基准测试）可能分别等于路线特定收敛时间的最小值和最大值。
The actual value falls within the accuracy interval [-(number of destinations/Offered Load), +(number of destinations/Offered Load)] around the value as measured using the Route-Specific Loss-Derived Method.
实际值在精度区间[-（目的地数量/提供的负载量），+（目的地数量/提供的负载量）]内，与使用路线特定损耗衍生方法测量的值一致。
For each test case, it is RECOMMENDED that the reporting tables below be completed. All time values SHOULD be reported with a sufficiently high resolution (fractions of a second sufficient to distinguish significant differences between measured values).
对于每个测试用例，建议填写以下报告表。应以足够高的分辨率报告所有时间值（一秒的分数足以区分测量值之间的显著差异）。
Parameter Units
------------------------------------- ---------------------------
Test Case test case number
Test Topology Test Topology Figure number
IGP (IS-IS, OSPF, other)
Interface Type (GigE, POS, ATM, other)
Packet Size offered to DUT bytes
Offered Load packets per second
IGP Routes Advertised to DUT number of IGP routes
Nodes in Emulated Network number of nodes
Number of Parallel or ECMP links number of links
Number of Routes Measured number of routes
Packet Sampling Interval on Tester seconds
Forwarding Delay Threshold seconds
Parameter Units
------------------------------------- ---------------------------
Test Case test case number
Test Topology Test Topology Figure number
IGP (IS-IS, OSPF, other)
Interface Type (GigE, POS, ATM, other)
Packet Size offered to DUT bytes
Offered Load packets per second
IGP Routes Advertised to DUT number of IGP routes
Nodes in Emulated Network number of nodes
Number of Parallel or ECMP links number of links
Number of Routes Measured number of routes
Packet Sampling Interval on Tester seconds
Forwarding Delay Threshold seconds
Timer Values configured on DUT: Interface Failure Indication Delay seconds IGP Hello Timer seconds IGP Dead-Interval or Hold-Time seconds LSA/LSP Generation Delay seconds LSA/LSP Flood Packet Pacing seconds LSA/LSP Retransmission Packet Pacing seconds Route Calculation Delay seconds
在DUT上配置的计时器值：接口故障指示延迟秒IGP Hello Timer秒IGP死区间隔或保持时间秒LSA/LSP生成延迟秒LSA/LSP洪泛数据包调整秒LSA/LSP重传数据包调整秒路由计算延迟秒
Test Details:
测试详情：
Describe the IGP extensions and IGP security mechanisms that are configured on the DUT.
描述在DUT上配置的IGP扩展和IGP安全机制。
Describe how the various fields on the IP and contained headers for the packets for the Offered Load are generated (Section 5.6).
描述IP上的各个字段以及所提供负载的数据包的包含头是如何生成的（第5.6节）。
If the Offered Load matches a subset of routes, describe how this subset is selected.
如果提供的负载与路由子集匹配，请描述如何选择该子集。
Describe how the Convergence Event is applied; does it cause instantaneous traffic loss or not?
描述如何应用收敛事件；是否会造成瞬间交通损失？
The table below should be completed for the initial Convergence Event and the reversion Convergence Event.
初始收敛事件和回归收敛事件应填写下表。
Parameter Units
------------------------------------------- ----------------------
Convergence Event (initial or reversion)
Parameter Units
------------------------------------------- ----------------------
Convergence Event (initial or reversion)
Traffic Forwarding Metrics: Total number of packets offered to DUT number of packets Total number of packets forwarded by DUT number of packets Connectivity Packet Loss number of packets Convergence Packet Loss number of packets Out-of-Order Packets number of packets Duplicate Packets number of packets Excessive Forwarding Delay Packets number of packets
流量转发指标：提供给DUT的数据包总数数据包总数DUT转发的数据包总数数据包连接数据包丢失数据包聚合数据包丢失数据包无序数据包数数据包重复数据包数数据包过度转发延迟数据包数小包
Convergence Benchmarks: Rate-Derived Method: First Route Convergence Time seconds Full Convergence Time seconds Loss-Derived Method: Loss-Derived Convergence Time seconds Route-Specific Loss-Derived Method: Route-Specific Convergence Time[n] array of seconds Minimum Route-Specific Convergence Time seconds Maximum Route-Specific Convergence Time seconds Median Route-Specific Convergence Time seconds Average Route-Specific Convergence Time seconds
收敛基准：速率衍生方法：第一条路线收敛时间秒完全收敛时间秒损失衍生方法：损失衍生收敛时间秒路线特定损失衍生方法：路线特定收敛时间[n]秒数组最小路由特定收敛时间秒最大路由特定收敛时间秒中值路由特定收敛时间秒平均路由特定收敛时间秒
Loss of Connectivity Benchmarks: Loss-Derived Method: Loss-Derived Loss of Connectivity Period seconds Route-Specific Loss-Derived Method: Route Loss of Connectivity Period[n] array of seconds Minimum Route Loss of Connectivity Period seconds Maximum Route Loss of Connectivity Period seconds Median Route Loss of Connectivity Period seconds Average Route Loss of Connectivity Period seconds
连接丢失基准：丢失衍生方法：丢失衍生连接丢失周期秒路由特定丢失衍生方法：路由连接丢失周期[n]秒数组最小路由连接丢失周期秒最大路由连接丢失周期秒中间路由连接丢失周期秒平均路由连接丢失周期秒
It is RECOMMENDED that all applicable test cases be performed for best characterization of the DUT. The test cases follow a generic procedure tailored to the specific DUT configuration and Convergence Event [Po11t]. This generic procedure is as follows:
建议执行所有适用的测试用例，以获得DUT的最佳特性。测试用例遵循针对特定DUT配置和会聚事件量身定制的通用程序[Po11t]。一般程序如下：
1. Establish DUT and Tester configurations and advertise an IGP topology from Tester to DUT.
1. 建立DUT和测试仪配置，并在测试仪之间公布IGP拓扑。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is routed correctly. Verify if traffic is forwarded without Impaired Packets [Po06].
3. 验证通信是否正确路由。验证流量是否在没有受损数据包的情况下转发[Po06]。
4. Introduce Convergence Event [Po11t].
4. 引入收敛事件[Po11t]。
5. Measure First Route Convergence Time [Po11t].
5. 测量第一路收敛时间[Po11t]。
6. Measure Full Convergence Time [Po11t].
6. 测量完全收敛时间[Po11t]。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period [Po11t]. At the same time, measure number of Impaired Packets [Po11t].
8. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期[Po11t]。同时，测量受损数据包的数量[Po11t]。
9. Wait sufficient time for queues to drain. The duration of this time period MUST be larger than or equal to the Forwarding Delay Threshold.
9. 等待足够的时间让队列排空。此时间段的持续时间必须大于或等于转发延迟阈值。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Reverse Convergence Event.
11. 反向收敛事件。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets [Po11t].
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量[Po11t]。
Objective:
目标：
To obtain the IGP convergence measurements for Local Interface failure and recovery events. The Next-Best Egress Interface can be a single interface (Figure 1) or an ECMP set (Figure 2). The test with ECMP topology (Figure 2) is OPTIONAL.
获取本地接口故障和恢复事件的IGP收敛测量值。下一个最佳出口接口可以是单个接口（图1）或ECMP集（图2）。使用ECMP拓扑（图2）的测试是可选的。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the topology shown in Figures 1 or 2.
1. 使用图1或图2所示的拓扑将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is forwarded over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口转发。
4. Remove link on the Preferred Egress Interface of the DUT. This is the Convergence Event.
4. 移除DUT首选出口接口上的链路。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times and Loss-Derived Convergence Time. At the same time, measure number of Impaired Packets.
8. 测量特定于路线的收敛时间和损失导出的收敛时间。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore link on the Preferred Egress Interface of the DUT.
11. 恢复DUT首选出口接口上的链路。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Objective:
目标：
To obtain the IGP convergence measurements for Remote Interface failure and recovery events. The Next-Best Egress Interface can be a single interface (Figure 3) or an ECMP set (Figure 4). The test with ECMP topology (Figure 4) is OPTIONAL.
获取远程接口故障和恢复事件的IGP收敛度量。下一个最佳出口接口可以是单个接口（图3）或ECMP集（图4）。ECMP拓扑的测试（图4）是可选的。
Procedure:
程序：
1. Advertise an IGP topology from Tester to SUT using the topology shown in Figures 3 or 4.
1. 使用图3或图4所示的拓扑将IGP拓扑从测试仪播发到SUT。
2. Send Offered Load from Tester to SUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的SUT。
3. Verify traffic is forwarded over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口转发。
4. Remove link on the interface of the Tester connected to the Preferred Egress Interface of the SUT. This is the Convergence Event.
4. 移除连接至SUT首选出口接口的测试仪接口上的链接。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times and Loss-Derived Convergence Time. At the same time, measure number of Impaired Packets.
8. 测量特定于路线的收敛时间和损失导出的收敛时间。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore link on the interface of the Tester connected to the Preferred Egress Interface of the SUT.
11. 恢复连接到SUT首选出口接口的测试仪接口上的链接。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Discussion:
讨论：
In this test case, there is a possibility of a packet-forwarding loop that may occur transiently between DUT1 and DUT2 during convergence (micro-loop, see [Sh10]), which may increase the measured convergence times and loss of connectivity periods.
在该测试用例中，在收敛过程中，DUT1和DUT2之间可能会出现短暂的包转发循环（微循环，见[Sh10]），这可能会增加测量的收敛时间和连接丢失周期。
8.1.3. Convergence Due to ECMP Member Local Interface Failure and Recovery
8.1.3. ECMP成员本地接口故障和恢复导致的收敛
Objective:
目标：
To obtain the IGP convergence measurements for Local Interface link failure and recovery events of an ECMP Member.
获取ECMP成员的本地接口链路故障和恢复事件的IGP收敛度量。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the test setup shown in Figure 5.
1. 使用图5所示的测试设置将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is forwarded over the ECMP member interface of the DUT that will be failed in the next step.
3. 验证在下一步将失败的DUT的ECMP成员接口上转发的通信量。
4. Remove link on one of the ECMP member interfaces of the DUT. This is the Convergence Event.
4. 移除DUT的一个ECMP成员接口上的链接。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times and Loss-Derived Convergence Time. At the same time, measure number of Impaired Packets.
8. 测量特定于路线的收敛时间和损失导出的收敛时间。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore link on the ECMP member interface of the DUT.
11. 恢复DUT的ECMP成员接口上的链接。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
8.1.4. Convergence Due to ECMP Member Remote Interface Failure and Recovery
8.1.4. ECMP成员远程接口故障和恢复导致聚合
Objective:
目标：
To obtain the IGP convergence measurements for Remote Interface link failure and recovery events for an ECMP Member.
获取ECMP成员远程接口链路故障和恢复事件的IGP聚合度量。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the test setup shown in Figure 6.
1. 使用图6所示的测试设置将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is forwarded over the ECMP member interface of the DUT that will be failed in the next step.
3. 验证在下一步将失败的DUT的ECMP成员接口上转发的通信量。
4. Remove link on the interface of the Tester to R2. This is the Convergence Event Trigger.
4. 移除测试仪与R2接口上的链接。这是聚合事件触发器。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times and Loss-Derived Convergence Time. At the same time, measure number of Impaired Packets.
8. 测量特定于路线的收敛时间和损失导出的收敛时间。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore link on the interface of the Tester to R2.
11. 将测试仪界面上的链接恢复到R2。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Discussion:
讨论：
In this test case, there is a possibility of a packet-forwarding loop that may occur temporarily between DUT1 and DUT2 during convergence (micro-loop, see [Sh10]), which may increase the measured convergence times and loss of connectivity periods.
在该测试用例中，在收敛期间，可能会在DUT1和DUT2之间临时发生分组转发循环（微循环，见[Sh10]），这可能会增加测量的收敛时间和连接丢失周期。
Objective:
目标：
To obtain the IGP convergence measurements for local link failure and recovery events for a member of a parallel link. The links can be used for data load-balancing
获取并行链路成员的本地链路故障和恢复事件的IGP收敛度量。这些链接可用于数据负载平衡
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the test setup shown in Figure 7.
1. 使用图7所示的测试设置将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is forwarded over the parallel link member that will be failed in the next step.
3. 验证是否通过将在下一步失败的并行链路成员转发通信量。
4. Remove link on one of the parallel link member interfaces of the DUT. This is the Convergence Event.
4. 移除DUT的一个平行连接件接口上的连接件。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times and Loss-Derived Convergence Time. At the same time, measure number of Impaired Packets.
8. 测量特定于路线的收敛时间和损失导出的收敛时间。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore link on the Parallel Link member interface of the DUT.
11. 恢复DUT并行链路成员接口上的链路。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Objective:
目标：
To obtain the IGP convergence measurements for a local Layer 2 loss and recovery.
获得局部第2层损耗和恢复的IGP收敛测量值。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the topology shown in Figure 1.
1. 使用图1所示的拓扑将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is routed over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口路由。
4. Remove Layer 2 session from Preferred Egress Interface of the DUT. This is the Convergence Event.
4. 从DUT的首选出口接口移除第2层会话。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
8. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore Layer 2 session on Preferred Egress Interface of the DUT.
11. 在DUT的首选出口接口上恢复第2层会话。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Discussion:
讨论：
When removing the Layer 2 session, the physical layer must stay up. Configure IGP timers such that the IGP adjacency does not time out before Layer 2 failure is detected.
移除第2层会话时，物理层必须保持正常。配置IGP定时器，使IGP邻接在检测到第2层故障之前不会超时。
To measure convergence time, traffic SHOULD start dropping on the Preferred Egress Interface on the instant the Layer 2 session is removed. Alternatively, the Tester SHOULD record the time the instant Layer 2 session is removed, and traffic loss SHOULD only be measured on the Next-Best Egress Interface. For loss-derived benchmarks, the time of the Start Traffic Instant SHOULD be recorded as well. See Section 4.1.
为了测量收敛时间，在删除第2层会话的那一刻，流量应该开始在首选出口接口上下降。或者，测试人员应记录即时第2层会话被删除的时间，并且仅应在次优出口接口上测量流量损失。对于损失衍生基准，还应记录开始流量瞬间的时间。见第4.1节。
Objective:
目标：
To obtain the IGP convergence measurements for loss and recovery of an IGP Adjacency. The IGP adjacency is removed on the Tester by disabling processing of IGP routing protocol packets on the Tester.
获得IGP邻接丢失和恢复的IGP收敛度量。通过禁用测试仪上IGP路由协议数据包的处理，可以在测试仪上删除IGP邻接。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the topology shown in Figure 1.
1. 使用图1所示的拓扑将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is routed over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口路由。
4. Remove IGP adjacency from the Preferred Egress Interface while the Layer 2 session MUST be maintained. This is the Convergence Event.
4. 从首选出口接口移除IGP邻接，同时必须保持第2层会话。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
8. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Restore IGP session on Preferred Egress Interface of the DUT.
11. 在DUT的首选出口接口上恢复IGP会话。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Discussion:
讨论：
Configure Layer 2 such that Layer 2 does not time out before IGP adjacency failure is detected.
配置第2层，使第2层在检测到IGP邻接故障之前不会超时。
To measure convergence time, traffic SHOULD start dropping on the Preferred Egress Interface on the instant the IGP adjacency is removed. Alternatively, the Tester SHOULD record the time the instant the IGP adjacency is removed and traffic loss SHOULD only be measured on the Next-Best Egress Interface. For loss-derived benchmarks, the time of the Start Traffic Instant SHOULD be recorded as well. See Section 4.1.
为了测量收敛时间，在IGP邻接被移除的瞬间，流量应开始在首选出口接口上下降。或者，测试仪应记录IGP邻接被移除的瞬间时间，并且仅应在次优出口接口上测量交通损失。对于损失衍生基准，还应记录开始流量瞬间的时间。见第4.1节。
Objective:
目标：
To obtain the IGP convergence measurements for route withdrawal and re-advertisement.
获取路线退出和重新公布的IGP收敛度量。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the topology shown in Figure 1. The routes that will be withdrawn MUST be a set of leaf routes advertised by at least two nodes in the emulated topology. The topology SHOULD be such that before the withdrawal the DUT prefers the leaf routes advertised by a node "nodeA" via the Preferred Egress Interface, and after the withdrawal the DUT prefers the leaf routes advertised by a node "nodeB" via the Next-Best Egress Interface.
1. 使用图1所示的拓扑将IGP拓扑从测试仪播发到DUT。将被撤销的路由必须是由仿真拓扑中至少两个节点播发的一组叶路由。拓扑应该是这样的：在退出之前，DUT首选节点“nodeA”通过首选出口接口通告的叶路由，在退出之后，DUT首选节点“nodeB”通过次优出口接口通告的叶路由。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is routed over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口路由。
4. The Tester withdraws the set of IGP leaf routes from nodeA. This is the Convergence Event. The withdrawal update message SHOULD be a single unfragmented packet. If the routes cannot be withdrawn by a single packet, the messages SHOULD be sent using the same pacing characteristics as the DUT. The Tester MAY record the time it sends the withdrawal message(s).
4. 测试仪从节点A中提取IGP叶路由集。这就是融合事件。取款更新消息应该是一个单独的未分割数据包。如果单个数据包无法撤回路由，则应使用与DUT相同的起搏特性发送消息。测试仪可记录其发送撤销信息的时间。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
8. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Re-advertise the set of withdrawn IGP leaf routes from nodeA emulated by the Tester. The update message SHOULD be a single unfragmented packet. If the routes cannot be advertised by a single packet, the messages SHOULD be sent using the same pacing characteristics as the DUT. The Tester MAY record the time it sends the update message(s).
11. 重新公布测试仪模拟的从节点A撤回的IGP叶路由集。更新消息应该是单个未分段的数据包。如果路由不能通过单个数据包播发，则应使用与DUT相同的起搏特性发送消息。测试仪可能会记录发送更新消息的时间。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Discussion:
讨论：
To measure convergence time, traffic SHOULD start dropping on the Preferred Egress Interface on the instant the routes are withdrawn by the Tester. Alternatively, the Tester SHOULD record the time the instant the routes are withdrawn, and traffic loss SHOULD only be measured on the Next-Best Egress Interface. For loss-derived benchmarks, the time of the Start Traffic Instant SHOULD be recorded as well. See Section 4.1.
为了测量会聚时间，测试人员撤出路线时，交通量应立即开始在首选出口界面上下降。或者，测试人员应记录退出路线的时间，交通损失应仅在次优出口界面上测量。对于损失衍生基准，还应记录开始流量瞬间的时间。见第4.1节。
Objective:
目标：
To obtain the IGP convergence measurements for administratively disabling and enabling a Local Interface.
获取IGP收敛测量值，用于管理性禁用和启用本地接口。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the topology shown in Figure 1.
1. 使用图1所示的拓扑将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is routed over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口路由。
4. Administratively disable the Preferred Egress Interface of the DUT. This is the Convergence Event.
4. 以管理方式禁用DUT的首选出口接口。这就是融合事件。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
8. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. Administratively enable the Preferred Egress Interface of the DUT.
11. 以管理方式启用DUT的首选出口接口。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Objective:
目标：
To obtain the IGP convergence measurements for route cost change.
获取路线成本变化的IGP收敛度量。
Procedure:
程序：
1. Advertise an IGP topology from Tester to DUT using the topology shown in Figure 1.
1. 使用图1所示的拓扑将IGP拓扑从测试仪播发到DUT。
2. Send Offered Load from Tester to DUT on Ingress Interface.
2. 将提供的负载从测试仪发送到入口接口上的DUT。
3. Verify traffic is routed over Preferred Egress Interface.
3. 验证流量是否通过首选出口接口路由。
4. The Tester, emulating the neighbor node, increases the cost for all IGP routes at the Preferred Egress Interface of the DUT so that the Next-Best Egress Interface becomes the preferred path. The update message advertising the higher cost MUST be a single unfragmented packet. This is the Convergence Event. The Tester MAY record the time it sends the update message advertising the higher cost on the Preferred Egress Interface.
4. 测试仪模拟邻居节点，增加DUT首选出口接口处所有IGP路由的成本，以便次优出口接口成为首选路径。宣传较高成本的更新消息必须是单个未分割的数据包。这就是融合事件。测试仪可记录其发送更新消息的时间，该消息在首选出口接口上宣传较高的成本。
5. Measure First Route Convergence Time.
5. 测量第一路收敛时间。
6. Measure Full Convergence Time.
6. 测量完全收敛时间。
7. Stop Offered Load.
7. 停止提供的负载。
8. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
8. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
9. Wait sufficient time for queues to drain.
9. 等待足够的时间让队列排空。
10. Restart Offered Load.
10. 重新启动提供的加载。
11. The Tester, emulating the neighbor node, decreases the cost for all IGP routes at the Preferred Egress Interface of the DUT so that the Preferred Egress Interface becomes the preferred path. The update message advertising the lower cost MUST be a single unfragmented packet.
11. 测试仪模拟邻居节点，降低DUT首选出口接口处所有IGP路由的成本，以便首选出口接口成为首选路径。宣传较低成本的更新消息必须是单个未分割的数据包。
12. Measure First Route Convergence Time.
12. 测量第一路收敛时间。
13. Measure Full Convergence Time.
13. 测量完全收敛时间。
14. Stop Offered Load.
14. 停止提供的负载。
15. Measure Route-Specific Convergence Times, Loss-Derived Convergence Time, Route Loss of Connectivity Periods, and Loss-Derived Loss of Connectivity Period. At the same time, measure number of Impaired Packets.
15. 测量特定于路由的收敛时间、损失衍生的收敛时间、路由连接丢失周期和损失衍生的连接丢失周期。同时，测量受损数据包的数量。
Discussion:
讨论：
To measure convergence time, traffic SHOULD start dropping on the Preferred Egress Interface on the instant the cost is changed by the Tester. Alternatively, the Tester SHOULD record the time the instant the cost is changed, and traffic loss SHOULD only be measured on the Next-Best Egress Interface. For loss-derived benchmarks, the time of the Start Traffic Instant SHOULD be recorded as well. See Section 4.1.
为了测量收敛时间，流量应该在测试人员改变成本的那一刻就开始在首选出口接口上下降。或者，测试人员应记录成本变化的瞬间时间，交通损失应仅在次优出口界面上测量。对于损失衍生基准，还应记录开始流量瞬间的时间。见第4.1节。
Benchmarking activities as described in this memo are limited to technology characterization using controlled stimuli in a laboratory environment, with dedicated address space and the constraints specified in the sections above.
本备忘录中所述的基准测试活动仅限于在实验室环境中使用受控刺激进行技术表征，具有专用地址空间和上述章节中规定的约束条件。
The benchmarking network topology will be an independent test setup and MUST NOT be connected to devices that may forward the test traffic into a production network or misroute traffic to the test management network.
基准网络拓扑将是一个独立的测试设置，不得连接到可能将测试流量转发到生产网络或将流量错误路由到测试管理网络的设备。
Further, benchmarking is performed on a "black-box" basis, relying solely on measurements observable external to the DUT/SUT.
此外，基准测试是在“黑盒”的基础上进行的，仅依赖于DUT/SUT外部可观察到的测量。
Special capabilities SHOULD NOT exist in the DUT/SUT specifically for benchmarking purposes. Any implications for network security arising from the DUT/SUT SHOULD be identical in the lab and in production networks.
DUT/SUT中不应存在专门用于基准测试的特殊能力。DUT/SUT对网络安全的任何影响应在实验室和生产网络中相同。
Thanks to Sue Hares, Al Morton, Kevin Dubray, Ron Bonica, David Ward, Peter De Vriendt, Anuj Dewagan, Julien Meuric, Adrian Farrel, Stewart Bryant, and the Benchmarking Methodology Working Group for their contributions to this work.
感谢Sue Hares、Al Morton、Kevin Dubrey、Ron Bonica、David Ward、Peter De Vriendt、Anuj Dewagan、Julien Meuria、Adrian Farrel、Stewart Bryant和基准方法工作组对本工作的贡献。
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[Br91]Bradner，S.，“网络互连设备的基准术语”，RFC 1242，1991年7月。
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[Br97]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[Br99] Bradner, S. and J. McQuaid, "Benchmarking Methodology for Network Interconnect Devices", RFC 2544, March 1999.
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[Ca90] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and dual environments", RFC 1195, December 1990.
[Ca90]Callon，R.，“OSI IS-IS在TCP/IP和双环境中路由的使用”，RFC 1195，1990年12月。
[Co08] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF for IPv6", RFC 5340, July 2008.
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[De02] Demichelis, C. and P. Chimento, "IP Packet Delay Variation Metric for IP Performance Metrics (IPPM)", RFC 3393, November 2002.
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[Ko02] Koodli, R. and R. Ravikanth, "One-way Loss Pattern Sample Metrics", RFC 3357, August 2002.
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[Ma05] Manral, V., White, R., and A. Shaikh, "Benchmarking Basic OSPF Single Router Control Plane Convergence", RFC 4061, April 2005.
[Ma05]Manral，V.，White，R.，和A.Shaikh，“基准测试基本OSPF单路由器控制平面收敛”，RFC 4061，2005年4月。
[Ma05c] Manral, V., White, R., and A. Shaikh, "Considerations When Using Basic OSPF Convergence Benchmarks", RFC 4063, April 2005.
[Ma05c]Manral，V.，White，R.，和A.Shaikh，“使用基本OSPF收敛基准时的注意事项”，RFC 4063，2005年4月。
[Ma05t] Manral, V., White, R., and A. Shaikh, "OSPF Benchmarking Terminology and Concepts", RFC 4062, April 2005.
[Ma05t]Manral，V.，White，R.，和A.Shaikh，“OSPF基准术语和概念”，RFC 4062，2005年4月。
[Ma98] Mandeville, R., "Benchmarking Terminology for LAN Switching Devices", RFC 2285, February 1998.
[Ma98]Mandeville，R.，“局域网交换设备的基准术语”，RFC 2285，1998年2月。
[Mo98] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[Mo98]Moy，J.，“OSPF版本2”，STD 54，RFC 23281998年4月。
[Ne07] Newman, D. and T. Player, "Hash and Stuffing: Overlooked Factors in Network Device Benchmarking", RFC 4814, March 2007.
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[Po11t] Poretsky, S., Imhoff, B., and K. Michielsen, "Terminology for Benchmarking Link-State IGP Data-Plane Route Convergence", RFC 6412, November 2011.
[Po11t]Poretsky，S.，Imhoff，B.，和K.Michielsen，“链路状态IGP数据平面路由聚合基准术语”，RFC 6412，2011年11月。
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Authors' Addresses
作者地址
Scott Poretsky Allot Communications 300 TradeCenter Woburn, MA 01801 USA
Scott Poretsky Allot Communications 300美国马萨诸塞州沃本贸易中心01801
Phone: + 1 508 309 2179
EMail: sporetsky@allot.com
Phone: + 1 508 309 2179
EMail: sporetsky@allot.com
Brent Imhoff Juniper Networks 1194 North Mathilda Ave Sunnyvale, CA 94089 USA
布伦特·伊姆霍夫·朱尼珀网络公司美国加利福尼亚州桑尼维尔北马蒂尔达大街1194号，邮编94089
Phone: + 1 314 378 2571
EMail: bimhoff@planetspork.com
Phone: + 1 314 378 2571
EMail: bimhoff@planetspork.com
Kris Michielsen Cisco Systems 6A De Kleetlaan Diegem, BRABANT 1831 Belgium
Kris Michielsen Cisco Systems 6A De Kleetlaan Diegem，比利时布拉班特1831
EMail: kmichiel@cisco.com
EMail: kmichiel@cisco.com