Internet Engineering Task Force (IETF) E. Bellagamba
Request for Comments: 7759
Category: Standards Track G. Mirsky
ISSN: 2070-1721 Ericsson
L. Andersson
Huawei Technologies
P. Skoldstrom
Acreo AB
D. Ward
Cisco
J. Drake
Juniper
February 2016
Internet Engineering Task Force (IETF) E. Bellagamba
Request for Comments: 7759
Category: Standards Track G. Mirsky
ISSN: 2070-1721 Ericsson
L. Andersson
Huawei Technologies
P. Skoldstrom
Acreo AB
D. Ward
Cisco
J. Drake
Juniper
February 2016
Configuration of Proactive Operations, Administration, and Maintenance (OAM) Functions for MPLS-Based Transport Networks Using Label Switched Path (LSP) Ping
使用标签交换路径（LSP）Ping为基于MPLS的传输网络配置主动操作、管理和维护（OAM）功能
Abstract
摘要
This specification describes the configuration of proactive MPLS-TP Operations, Administration, and Maintenance (OAM) functions for a given Label Switched Path (LSP) using a set of TLVs that are carried by the LSP Ping protocol.
本规范描述了使用由LSP Ping协议承载的一组TLV为给定标签交换路径（LSP）配置主动MPLS-TP操作、管理和维护（OAM）功能。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
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). Further information on Internet Standards is available in 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。有关互联网标准的更多信息，请参见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/rfc7759.
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/rfc7759.
Copyright Notice
版权公告
Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2016 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction ....................................................3
1.1. Conventions Used in This Document ..........................4
1.1.1. Terminology .........................................4
1.1.2. Requirements Language ...............................5
2. Theory of Operations ............................................5
2.1. MPLS OAM Configuration Operation Overview ..................5
2.1.1. Configuration of BFD Sessions .......................5
2.1.2. Configuration of Performance Monitoring .............6
2.1.3. Configuration of Fault Management Signals ...........6
2.2. MPLS OAM Functions TLV .....................................7
2.2.1. BFD Configuration Sub-TLV ...........................9
2.2.2. BFD Local Discriminator Sub-TLV ....................11
2.2.3. BFD Negotiation Timer Parameters Sub-TLV ...........11
2.2.4. BFD Authentication Sub-TLV .........................13
2.2.5. Traffic Class Sub-TLV ..............................14
2.2.6. Performance Monitoring Sub-TLV .....................14
2.2.7. PM Loss Measurement Sub-TLV ........................17
2.2.8. PM Delay Measurement Sub-TLV .......................18
2.2.9. Fault Management Signal Sub-TLV ....................20
2.2.10. Source MEP-ID Sub-TLV .............................21
3. Summary of MPLS OAM Configuration Errors .......................22
4. IANA Considerations ............................................23
4.1. TLV and Sub-TLV Allocation ................................23
4.2. MPLS OAM Function Flags Allocation ........................24
4.3. OAM Configuration Errors ..................................25
5. Security Considerations ........................................26
6. References .....................................................26
6.1. Normative References ......................................26
6.2. Informative References ....................................27
Acknowledgements .................................................28
Authors' Addresses ................................................29
1. Introduction ....................................................3
1.1. Conventions Used in This Document ..........................4
1.1.1. Terminology .........................................4
1.1.2. Requirements Language ...............................5
2. Theory of Operations ............................................5
2.1. MPLS OAM Configuration Operation Overview ..................5
2.1.1. Configuration of BFD Sessions .......................5
2.1.2. Configuration of Performance Monitoring .............6
2.1.3. Configuration of Fault Management Signals ...........6
2.2. MPLS OAM Functions TLV .....................................7
2.2.1. BFD Configuration Sub-TLV ...........................9
2.2.2. BFD Local Discriminator Sub-TLV ....................11
2.2.3. BFD Negotiation Timer Parameters Sub-TLV ...........11
2.2.4. BFD Authentication Sub-TLV .........................13
2.2.5. Traffic Class Sub-TLV ..............................14
2.2.6. Performance Monitoring Sub-TLV .....................14
2.2.7. PM Loss Measurement Sub-TLV ........................17
2.2.8. PM Delay Measurement Sub-TLV .......................18
2.2.9. Fault Management Signal Sub-TLV ....................20
2.2.10. Source MEP-ID Sub-TLV .............................21
3. Summary of MPLS OAM Configuration Errors .......................22
4. IANA Considerations ............................................23
4.1. TLV and Sub-TLV Allocation ................................23
4.2. MPLS OAM Function Flags Allocation ........................24
4.3. OAM Configuration Errors ..................................25
5. Security Considerations ........................................26
6. References .....................................................26
6.1. Normative References ......................................26
6.2. Informative References ....................................27
Acknowledgements .................................................28
Authors' Addresses ................................................29
The MPLS Transport Profile (MPLS-TP) describes a profile of MPLS that enables operational models typical in transport networks while providing additional Operations, Administration, and Maintenance (OAM), survivability, and other maintenance functions not currently supported by MPLS. [RFC5860] defines the requirements for the OAM functionality of MPLS-TP.
MPLS传输配置文件（MPLS-TP）描述了MPLS的配置文件，该配置文件支持传输网络中典型的操作模型，同时提供MPLS目前不支持的其他操作、管理和维护（OAM）、生存性和其他维护功能。[RFC5860]定义了MPLS-TP的OAM功能要求。
This document describes the configuration of proactive MPLS-TP OAM functions for a given Label Switched Path (LSP) using TLVs carried in LSP Ping [RFC4379]. In particular, it specifies the mechanisms necessary to establish MPLS-TP OAM entities at the maintenance points for monitoring and performing measurements on an LSP, as well as defining information elements and procedures to configure proactive MPLS-TP OAM functions running between Label Edge Routers (LERs). Initialization and control of on-demand MPLS-TP OAM functions are expected to be carried out by directly accessing network nodes via a management interface; hence, configuration and control of on-demand OAM functions are out of scope for this document.
本文档描述了使用LSP Ping[RFC4379]中携带的TLV为给定标签交换路径（LSP）配置主动MPLS-TP OAM功能。特别是，它规定了在维护点建立MPLS-TP OAM实体所需的机制，用于监控和执行LSP上的测量，以及定义信息元素和过程，以配置在标签边缘路由器（LER）之间运行的主动式MPLS-TP OAM功能。按需MPLS-TP OAM功能的初始化和控制预计将通过管理接口直接访问网络节点来执行；因此，按需OAM功能的配置和控制超出了本文档的范围。
The Transport Profile of MPLS must, by definition [RFC5654], be capable of operating without a control plane. Therefore, there are a few options for configuring MPLS-TP OAM: without a control plane using a Network Management System (NMS), implementing LSP Ping instead or with a control plane implementing extensions to signaling protocols RSVP Traffic Engineering (RSVP-TE) [RFC3209] and/or Targeted LDP [RFC5036].
根据定义[RFC5654]，MPLS的传输配置文件必须能够在没有控制平面的情况下运行。因此，配置MPLS-TP OAM有几个选项：没有使用网络管理系统（NMS）的控制平面，而是实现LSP Ping，或者使用实现信令协议RSVP流量工程（RSVP-TE）[RFC3209]和/或目标LDP[RFC5036]扩展的控制平面。
Proactive MPLS-TP OAM is performed by a set of protocols:
Bidirectional Forwarding Detection (BFD) [RFC6428] for Continuity
Check/Connectivity Verification, the Delay Measurement (DM) protocol
[RFC6374], [RFC6375] for delay and delay variation (jitter)
measurements, and the Loss Measurement (LM) protocol [RFC6374],
[RFC6375] for packet loss and throughput measurements. Additionally,
there are a number of Fault Management Signals that can be configured
[RFC6427].
Proactive MPLS-TP OAM is performed by a set of protocols:
Bidirectional Forwarding Detection (BFD) [RFC6428] for Continuity
Check/Connectivity Verification, the Delay Measurement (DM) protocol
[RFC6374], [RFC6375] for delay and delay variation (jitter)
measurements, and the Loss Measurement (LM) protocol [RFC6374],
[RFC6375] for packet loss and throughput measurements. Additionally,
there are a number of Fault Management Signals that can be configured
[RFC6427].
BFD is a protocol that provides low-overhead, fast detection of failures in the path between two forwarding engines, including the interfaces, data link(s), and to the extent possible, the forwarding engines themselves. BFD can be used to detect the continuity and mis-connection defects of MPLS-TP point-to-point and might also be extended to support point-to-multipoint LSPs.
BFD是一种协议，它提供低开销、快速检测两个转发引擎（包括接口、数据链路）之间路径中的故障，并尽可能检测转发引擎本身。BFD可用于检测MPLS-TP点对点的连续性和误连接缺陷，也可扩展为支持点对多点LSP。
The delay and loss measurements protocols [RFC6374] and [RFC6375] use a simple query/response model for performing both unidirectional and bidirectional measurements that allow the originating node to measure
延迟和损耗测量协议[RFC6374]和[RFC6375]使用一个简单的查询/响应模型来执行单向和双向测量，从而允许发起节点进行测量
packet loss and delay in forward, or forward and reverse directions. By timestamping and/or writing current packet counters to the measurement packets (four times, Transmit and Receive in both directions), current delays and packet losses can be calculated. By performing successive delay measurements, the delay and/or inter-packet delay variation (jitter) can be calculated. Current throughput can be calculated from the packet loss measurements by dividing the number of packets sent/received with the time it took to perform the measurement, given by the timestamp in the LM header. Combined with a packet generator, the throughput measurement can be used to measure the maximum capacity of a particular LSP. It should be noted that this document does not specify how to configure on-demand throughput estimates based on saturating the connection as defined in [RFC6371]; rather, it only specifies how to enable the estimation of the current throughput based on loss measurements.
正向、正向和反向的数据包丢失和延迟。通过对测量数据包进行时间戳和/或写入当前数据包计数器（四次，双向发送和接收），可以计算当前延迟和数据包丢失。通过执行连续的延迟测量，可以计算延迟和/或包间延迟变化（抖动）。通过将发送/接收的数据包数量除以执行测量所花费的时间（由LM报头中的时间戳给出），可以从数据包丢失测量中计算当前吞吐量。结合分组生成器，吞吐量测量可用于测量特定LSP的最大容量。应注意的是，本文件未规定如何根据[RFC6371]中定义的饱和连接配置按需吞吐量估计值；相反，它只指定如何基于损耗测量来估计当前吞吐量。
BFD - Bidirectional Forwarding Detection
双向转发检测
DM - Delay Measurement
延迟测量
FMS - Fault Management Signal
故障管理信号
G-ACh - Generic Associated Channel
G-ACh-通用关联信道
LSP - Label Switched Path
标签交换路径
LM - Loss Measurement
LM-损耗测量
MEP - Maintenance Entity Group End Point
MEP-维修实体组终点
MPLS - Multi-Protocol Label Switching
多协议标签交换
MPLS-TP - MPLS Transport Profile
MPLS-TP-MPLS传输配置文件
NMS - Network Management System
网络管理系统
PM - Performance Monitoring
PM-性能监测
RSVP-TE - RSVP Traffic Engineering
RSVP-TE-RSVP交通工程
TC - Traffic Class
TC-交通等级
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119].
本文件中的关键词“必须”、“不得”、“要求”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照RFC 2119[RFC2119]中所述进行解释。
The MPLS-TP OAM tool set is described in [RFC6669].
[RFC6669]中描述了MPLS-TP OAM工具集。
LSP Ping, or alternatively RSVP-TE [RFC7487], can be used to easily enable the different OAM functions by setting the corresponding flags in the MPLS OAM Functions TLV (refer to Section 2.2). For a more detailed configuration, one may include sub-TLVs for the different OAM functions in order to specify various parameters in detail.
LSP Ping或RSVP-TE[RFC7487]可用于通过在MPLS OAM功能TLV中设置相应的标志来轻松启用不同的OAM功能（参考第2.2节）。对于更详细的配置，可以包括用于不同OAM功能的子tlv，以便详细地指定各种参数。
Typically, intermediate nodes simply forward OAM configuration TLVs to the end node without any processing or modification. At least one exception to this is if the FMS sub-TLV (refer to Section 2.2.9 ) is present. This sub-TLV MUST be examined even by intermediate nodes that support this extension. The sub-TLV MAY be present if a flag is set in the MPLS OAM Functions TLV.
通常，中间节点只是将OAM配置TLV转发到终端节点，而不进行任何处理或修改。如果存在FMS子TLV（参考第2.2.9节），则至少有一个例外情况。即使支持此扩展的中间节点也必须检查此子TLV。如果在MPLS OAM功能TLV中设置了标志，则子TLV可能存在。
For this specification, BFD MUST run in either one of the two modes:
对于本规范，BFD必须以两种模式之一运行：
o Asynchronous mode, where both sides are in active mode
o 异步模式，其中双方都处于活动模式
o Unidirectional mode
o 单向模式
In the simplest scenario, LSP Ping [RFC5884], or alternatively RSVP-TE [RFC7487], is used only to bootstrap a BFD session for an LSP, without any timer negotiation.
在最简单的场景中，LSP Ping[RFC5884]或RSVP-TE[RFC7487]仅用于引导LSP的BFD会话，而无需任何计时器协商。
Timer negotiation can be performed either in subsequent BFD control messages (in this case the operation is similar to bootstrapping based on LSP Ping described in [RFC5884]), or directly in the LSP Ping configuration messages.
计时器协商可以在后续BFD控制消息中执行（在这种情况下，操作类似于[RFC5884]中描述的基于LSP Ping的引导），也可以直接在LSP Ping配置消息中执行。
When BFD Control packets are transported in the Associated Channel Header (ACH) encapsulation, they are not protected by any end-to-end checksum; only lower layers provide error detection/correction. A single bit error, e.g., a flipped bit in the BFD State field, could cause the receiving end to wrongly conclude that the link is down and in turn trigger protection switching. To prevent this from
当BFD控制数据包在相关信道报头（ACH）封装中传输时，它们不受任何端到端校验和的保护；只有较低的层提供错误检测/纠正。单个位错误，例如BFD状态字段中的翻转位，可能会导致接收端错误地得出链路断开的结论，进而触发保护切换。为了防止这种情况发生
happening, the BFD Configuration sub-TLV (refer to Section 2.2.1) has an Integrity flag that, when set, enables BFD Authentication using Keyed SHA1 with an empty key (all 0s) [RFC5880]. This would make every BFD Control packet carry a SHA1 hash of itself that can be used to detect errors.
发生这种情况时，BFD配置子TLV（参考第2.2.1节）有一个完整性标志，当设置该标志时，使用带有空密钥（全部0）的密钥SHA1启用BFD身份验证[RFC5880]。这将使每个BFD控制数据包本身携带一个SHA1散列，可用于检测错误。
If BFD Authentication using a pre-shared key/password is desired (i.e., authentication and not only error detection), the BFD Authentication sub-TLV (refer to Section 2.2.4) MUST be included in the BFD Configuration sub-TLV. The BFD Authentication sub-TLV is used to specify which authentication method that should be used and which pre-shared key/password that should be used for this particular session. How the key exchange is performed is out of scope of this document.
如果需要使用预共享密钥/密码进行BFD身份验证（即，身份验证，而不仅仅是错误检测），BFD身份验证子TLV（参考第2.2.4节）必须包含在BFD配置子TLV中。BFD身份验证子TLV用于指定应使用哪种身份验证方法以及该特定会话应使用哪种预共享密钥/密码。如何执行密钥交换超出了本文档的范围。
It is possible to configure Performance Monitoring functionalities such as Loss, Delay, Delay/Interpacket Delay variation (jitter), and throughput as described in [RFC6374].
可以按照[RFC6374]中所述配置性能监控功能，如丢失、延迟、延迟/分组间延迟变化（抖动）和吞吐量。
When configuring Performance Monitoring functionalities, it is possible to choose either the default configuration, by only setting the respective flags in the MPLS OAM functions TLV, or a customized configuration. To customize the configuration, one would set the respective flags in the MPLS OAM functions TLV and include the respective Loss and/or Delay sub-TLVs.
在配置性能监视功能时，可以选择默认配置（仅通过在MPLS OAM功能TLV中设置相应的标志）或自定义配置。为了定制配置，可以在MPLS OAM功能TLV中设置相应的标志，并包括相应的丢失和/或延迟子TLV。
By setting the PM Loss flag in the MPLS OAM Functions TLV and including the PM Loss sub-TLV (refer to Section 2.2.7), one can configure the measurement interval and loss threshold values for triggering protection.
通过在MPLS OAM功能TLV中设置PM损耗标志并包括PM损耗子TLV（参考第2.2.7节），可以配置触发保护的测量间隔和损耗阈值。
Delay measurements are configured by setting the PM Delay flag in the MPLS OAM Functions TLV and by including the PM Delay sub-TLV (refer to Section 2.2.8), one can configure the measurement interval and the delay threshold values for triggering protection.
通过在MPLS OAM功能TLV中设置PM Delay标志，并通过包括PM Delay sub TLV（参考第2.2.8节），可以配置触发保护的测量间隔和延迟阈值来配置延迟测量。
To configure Fault Management Signals (FMSs) and their refresh time, the FMS Flag in the MPLS OAM Functions TLV MUST be set and the FMS sub-TLV MUST be included. When configuring an FMS, an implementation can enable the default configuration by setting the FMS Flag in the OAM Function Flags sub-TLV. In order to modify the default configuration, the MPLS OAM FMS sub-TLV MUST be included.
要配置故障管理信号（FMS）及其刷新时间，必须设置MPLS OAM功能TLV中的FMS标志，并且必须包括FMS子TLV。配置FMS时，实施可通过在OAM功能标志子TLV中设置FMS标志来启用默认配置。为了修改默认配置，必须包括MPLS OAM FMS子TLV。
If an intermediate point is meant to originate FMS messages, this means that such an intermediate point is associated with a Server MEP through a co-located MPLS-TP client/server adaptation function, and the Fault Management subscription flag in the MPLS OAM FMS sub-TLV has been set as an indication of the request to create the association at each intermediate node of the client LSP. The corresponding Server MEP needs to be configured by its own LSP Ping session or, alternatively, via a Network Management System (NMS) or RSVP-TE.
如果中间点旨在发起FMS消息，这意味着该中间点通过位于同一位置的MPLS-TP客户机/服务器适配功能与服务器MEP相关联，并且MPLS OAM FMS子TLV中的故障管理订阅标志已被设置为在客户端LSP的每个中间节点处创建关联的请求的指示。相应的服务器MEP需要通过其自己的LSP Ping会话进行配置，或者通过网络管理系统（NMS）或RSVP-TE进行配置。
The MPLS OAM Functions TLV presented in Figure 1 is carried as a TLV of the MPLS Echo Request/Reply messages [RFC4379].
图1中显示的MPLS OAM功能TLV作为MPLS回送请求/回复消息[RFC4379]的TLV携带。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS OAM Func. Type (27) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS OAM Function Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS OAM Func. Type (27) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS OAM Function Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: MPLS OAM Functions TLV Format
图1:MPLS OAM功能TLV格式
The MPLS OAM Functions TLV contains the MPLS OAM Function Flags field. The MPLS OAM Function Flags indicate which OAM functions should be activated as well as OAM function-specific sub-TLVs with configuration parameters for the particular function.
MPLS OAM函数TLV包含MPLS OAM函数标志字段。MPLS OAM功能标志指示应激活哪些OAM功能，以及具有特定功能配置参数的OAM功能特定子TLV。
Type: Indicates the MPLS OAM Functions TLV (Section 4).
类型：表示MPLS OAM功能TLV（第4节）。
Length: The length of the MPLS OAM Function Flags field including the total length of the sub-TLVs in octets.
长度：MPLS OAM函数标志字段的长度，包括子TLV的总长度（以八位字节为单位）。
MPLS OAM Function Flags: A bitmap numbered from left to right as shown in Figure 2. These flags are managed by IANA (refer to Section 4.2). Flags defined in this document are presented in Table 2. Undefined flags MUST be set to zero and unknown flags MUST be ignored. The flags indicate what OAM is being configured and direct the presence of optional sub-TLVs as set out below.
MPLS OAM函数标志：从左到右编号的位图，如图2所示。这些标志由IANA管理（参考第4.2节）。本文件中定义的标志如表2所示。未定义的标志必须设置为零，并且必须忽略未知标志。这些标志指示正在配置的OAM，并指示可选子TLV的存在，如下所示。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|C|V|F|L|D|T|Unassigned MUST be zero (MBZ) |R|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|C|V|F|L|D|T|Unassigned MUST be zero (MBZ) |R|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: MPLS OAM Function Flags Format
图2:MPLS OAM函数标志格式
Sub-TLVs corresponding to the different flags are as follows. No meaning should be attached to the order of sub-TLVs.
与不同标志对应的子TLV如下所示。子TLV的顺序不应有任何含义。
o If a flag in the MPLS OAM Function Flags is set and the corresponding sub-TLVs listed below are absent, then this MPLS OAM function MUST be initialized according to its default settings. Default settings of MPLS OAM functions are outside the scope of this document.
o 如果设置了MPLS OAM功能标志中的标志，并且下面列出的相应子TLV不存在，则必须根据其默认设置初始化此MPLS OAM功能。MPLS OAM功能的默认设置超出了本文档的范围。
o If any sub-TLV is present without the corresponding flag being set, the sub-TLV SHOULD be ignored.
o 如果存在任何未设置相应标志的子TLV，则应忽略该子TLV。
o BFD Configuration sub-TLV, which MUST be included if either the CC, the CV, or both MPLS OAM Function flags are being set in the MPLS OAM Functions TLV.
o BFD配置子TLV，如果在MPLS OAM功能TLV中设置了CC、CV或两个MPLS OAM功能标志，则必须包括该子TLV。
o Performance Monitoring sub-TLV MUST be used to carry PM Loss sub-TLV and/or PM Delay sub-TLV. If neither one of these sub-TLVs is present, then Performance Monitoring sub-TLV SHOULD NOT be included. Empty, i.e., no enclosed sub-TLVs, Performance Monitoring sub-TLV SHOULD be ignored.
o 性能监测子TLV必须用于携带PM损耗子TLV和/或PM延迟子TLV。如果这些子TLV都不存在，则不应包括性能监控子TLV。空，即无封闭子TLV，应忽略性能监控子TLV。
o PM Loss sub-TLV MAY be included if the PM/Loss OAM Function flag is set. If the "PM Loss sub-TLV" is not included, default configuration values are used. Such sub-TLV MAY also be included in case the Throughput function flag is set and there is the need to specify a measurement interval different from the default ones. In fact, the throughput measurement makes use of the same tool as the loss measurement; hence, the same TLV is used.
o 如果设置了PM/Loss OAM功能标志，则可包括PM Loss子TLV。如果未包括“PM损耗子TLV”，则使用默认配置值。在设置了吞吐量功能标志并且需要指定不同于默认测量间隔的测量间隔的情况下，也可以包括这样的子TLV。事实上，吞吐量测量使用与损耗测量相同的工具；因此，使用相同的TLV。
o PM Delay sub-TLV MAY be included if the PM/Delay OAM Function flag is set. If the "PM Delay sub-TLV" is not included, default configuration values are used.
o 如果设置了PM/Delay OAM功能标志，则可以包括PM Delay sub TLV。如果未包括“PM延迟子TLV”，则使用默认配置值。
o FMS sub-TLV, that MAY be included if the FMS OAM Function flag is set. If the "FMS sub-TLV" is not included, default configuration values are used.
o FMS子TLV，如果设置了FMS OAM功能标志，则可能包括该子TLV。如果不包括“FMS子TLV”，则使用默认配置值。
If all flags in the MPLS OAM Function Flags field have the same value of zero, that MUST be interpreted as meaning that the MPLS OAM Functions TLV is not present in the MPLS Echo Request. If more than one MPLS OAM Functions TLV is present in the MPLS Echo request packet, then the first TLV SHOULD be processed and the rest ignored. Any parsing error within nested sub-TLVs that is not specified in Section 3 SHOULD be treated as described in [RFC4379].
如果MPLS OAM功能标志字段中的所有标志都具有相同的零值，则必须将其解释为意味着MPLS OAM功能TLV不存在于MPLS回显请求中。如果MPLS回送请求数据包中存在多个MPLS OAM功能TLV，则应处理第一个TLV，并忽略其余TLV。第3节中未规定的嵌套子TLV中的任何解析错误应按照[RFC4379]中的说明处理。
The BFD Configuration sub-TLV, depicted in Figure 3, is defined for BFD OAM-specific configuration parameters. The "BFD Configuration sub-TLV" is carried as a sub-TLV of the "OAM Functions TLV".
图3所示的BFD配置子TLV是为BFD OAM特定的配置参数定义的。“BFD配置子TLV”作为“OAM功能TLV”的子TLV携带。
This TLV accommodates generic BFD OAM information and carries sub-TLVs.
该TLV容纳通用BFD OAM信息并承载子TLV。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFD Conf. Sub-type (100) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Vers.|N|S|I|G|U|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFD Conf. Sub-type (100) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Vers.|N|S|I|G|U|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: BFD Configuration Sub-TLV Format
图3:BFD配置子TLV格式
Sub-type: Indicates a new sub-type, the BFD Configuration sub-TLV (value 100).
子类型：表示新的子类型，BFD配置子TLV（值100）。
Length: Indicates the length of the Value field in octets.
长度：以八位字节表示值字段的长度。
Version: Identifies the BFD protocol version. If a node does not support a specific BFD version, an error must be generated: "OAM Problem/Unsupported BFD Version".
版本：标识BFD协议版本。如果节点不支持特定的BFD版本，则必须生成错误：“OAM问题/不支持的BFD版本”。
BFD Negotiation (N): If set, timer negotiation/renegotiation via BFD Control Messages is enabled. When cleared, it is disabled and timer configuration is achieved using the BFD Negotiation Timer Parameters sub-TLV as described in Section 2.2.3.
BFD协商（N）：如果设置，则启用通过BFD控制消息的计时器协商/重新协商。清除后，将禁用该选项，并使用第2.2.3节所述BFD协商定时器参数子TLV实现定时器配置。
Symmetric session (S): If set, the BFD session MUST use symmetric timing values. If cleared, the BFD session MAY use any timing values either negotiated or explicitly configured.
对称会话：如果设置，BFD会话必须使用对称定时值。如果清除，BFD会话可以使用协商或显式配置的任何定时值。
Integrity (I): If set, BFD Authentication MUST be enabled. If the BFD Configuration sub-TLV does not include a BFD Authentication sub-TLV, the authentication MUST use Keyed SHA1 with an empty pre-shared key (all 0s). If the egress LSR does not support BFD Authentication, an error MUST be generated: "OAM Problem/BFD Authentication unsupported". If the Integrity flag is clear, then Authentication MUST NOT be used.
完整性（I）：如果设置，则必须启用BFD身份验证。如果BFD配置子TLV不包括BFD身份验证子TLV，则身份验证必须使用带有空预共享密钥（所有0）的密钥SHA1。如果出口LSR不支持BFD身份验证，则必须生成错误：“OAM问题/BFD身份验证不受支持”。如果完整性标志已清除，则不得使用身份验证。
Encapsulation Capability (G): If set, it shows the capability of encapsulating BFD messages into the G-ACh channel. If both the G bit and U bit are set, configuration gives precedence to the G bit.
封装能力（G）：如果设置，则显示将BFD消息封装到G-ACh通道中的能力。如果同时设置了G位和U位，则配置优先于G位。
Encapsulation Capability (U): If set, it shows the capability of encapsulating BFD messages into IP/UDP packets. If both the G bit and U bit are set, configuration gives precedence to the G bit.
封装能力（U）：如果设置，则显示将BFD消息封装为IP/UDP数据包的能力。如果同时设置了G位和U位，则配置优先于G位。
If the egress LSR does not support any of the ingress LSR Encapsulation Capabilities, an error MUST be generated: "OAM Problem/ Unsupported BFD Encapsulation format".
如果出口LSR不支持任何入口LSR封装功能，则必须生成错误：“OAM问题/不支持的BFD封装格式”。
Bidirectional (B): If set, it configures BFD in the Bidirectional mode. If it is not set, it configures BFD in the unidirectional mode. In the second case, the source node does not expect any Discriminator values back from the destination node.
双向（B）：如果设置，则在双向模式下配置BFD。如果未设置，则在单向模式下配置BFD。在第二种情况下，源节点不希望从目标节点返回任何鉴别器值。
Reserved: Reserved for future specification; set to 0 on transmission and ignored when received.
预留：预留供将来规范使用；传输时设置为0，接收时忽略。
The BFD Configuration sub-TLV MUST include the following sub-TLVs in the MPLS Echo Request message:
BFD配置子TLV必须在MPLS回送请求消息中包含以下子TLV：
o BFD Local Discriminator sub-TLV, if the B flag is set in the MPLS Echo Request;
o 如果在MPLS回波请求中设置了B标志，则BFD本地鉴别器子TLV；
o BFD Negotiation Timer Parameters sub-TLV, if the N flag is cleared.
o 如果清除N标志，则BFD协商计时器参数子TLV。
The BFD Configuration sub-TLV MUST include the following sub-TLVs in the MPLS Echo Reply message:
BFD配置子TLV必须在MPLS回送回复消息中包含以下子TLV：
o BFD Local Discriminator sub-TLV;
o BFD局部鉴别器子TLV；
o BFD Negotiation Timer Parameters sub-TLV if:
o BFD协商定时器参数子TLV，如果：
* The N and S flags are cleared, or if:
* N和S标志被清除，或者：
* The N flag is cleared and the S flag is set, and the BFD Negotiation Timer Parameters sub-TLV received by the egress
* 清除N标志并设置S标志，出口接收BFD协商定时器参数sub TLV
contains unsupported values. In this case, an updated BFD Negotiation Timer Parameters sub-TLV, containing values supported by the egress node [RFC7419], is returned to the ingress.
包含不支持的值。在这种情况下，更新的BFD协商定时器参数sub-TLV（包含出口节点[RFC7419]支持的值）被返回到入口。
The BFD Local Discriminator sub-TLV is carried as a sub-TLV of the "BFD Configuration sub-TLV" and is depicted in Figure 4.
BFD本地鉴别器子TLV作为“BFD配置子TLV”的子TLV携带，如图4所示。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Locl. Discr. Sub-type (101) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Discriminator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Locl. Discr. Sub-type (101) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Discriminator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: BFD Local Discriminator Sub-TLV Format
图4:BFD本地鉴别器子TLV格式
Sub-type: Indicates a new sub-type, the "BFD Local Discriminator sub-TLV" (value 101).
子类型：表示新的子类型，“BFD本地鉴别器子TLV”（值101）。
Length: Indicates the length of the Value field in octets (4).
长度：以八位字节（4）表示值字段的长度。
Local Discriminator: A nonzero discriminator value that is unique in the context of the transmitting system that generates it. It is used to demultiplex multiple BFD sessions between the same pair of systems.
本地鉴别器：非零鉴别器值，在生成它的传输系统的上下文中是唯一的。它用于在同一对系统之间解复用多个BFD会话。
The BFD Negotiation Timer Parameters sub-TLV is carried as a sub-TLV of the BFD Configuration sub-TLV and is depicted in Figure 5.
BFD协商定时器参数子TLV作为BFD配置子TLV的子TLV携带，如图5所示。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Nego. Timer Sub-type (102) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Acceptable Min. Asynchronous TX interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Acceptable Min. Asynchronous RX interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Required Echo TX Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Nego. Timer Sub-type (102) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Acceptable Min. Asynchronous TX interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Acceptable Min. Asynchronous RX interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Required Echo TX Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: BFD Negotiation Timer Parameters Sub-TLV Format
图5:BFD协商定时器参数子TLV格式
Sub-type: Indicates a new sub-type, the BFD Negotiation Timer Parameters sub-TLV (value 102).
子类型：表示新的子类型，BFD协商计时器参数子TLV（值102）。
Length: Indicates the length of the Value field in octets (12). Acceptable Min. Asynchronous TX interval: If the S (symmetric) flag is set in the BFD Configuration sub-TLV, defined in Section 2.2.1, it expresses the desired time interval (in microseconds) at which the ingress LER intends to both transmit and receive BFD periodic control packets. If the receiving edge LSR cannot support such a value, it SHOULD reply with an interval greater than the one proposed.
长度：以八位字节（12）表示值字段的长度。可接受的最小异步发送间隔：如果在第2.2.1节中定义的BFD配置子TLV中设置了S（对称）标志，则表示入口LER打算发送和接收BFD周期控制数据包的所需时间间隔（以微秒为单位）。如果接收边缘LSR不能支持这样一个值，它应该以比建议的间隔更大的间隔进行应答。
If the S (symmetric) flag is cleared in the BFD Configuration sub-TLV, this field expresses the desired time interval (in microseconds) at which an edge LSR intends to transmit BFD periodic control packets in its transmitting direction.
如果在BFD配置子TLV中清除了S（对称）标志，则此字段表示边缘LSR打算在其发送方向上发送BFD周期性控制数据包的所需时间间隔（以微秒为单位）。
Acceptable Min. Asynchronous RX interval: If the S (symmetric) flag is set in the BFD Configuration sub-TLV, Figure 3, this field MUST be equal to Acceptable Min. Asynchronous TX interval and has no additional meaning respect to the one described for "Acceptable Min. Asynchronous TX interval".
可接受的最小异步接收间隔：如果在BFD配置子TLV（图3）中设置了S（对称）标志，则该字段必须等于可接受的最小异步发送间隔，并且与“可接受的最小异步发送间隔”所述的字段没有任何附加含义。
If the S (symmetric) flag is cleared in the BFD Configuration sub-TLV, it expresses the minimum time interval (in microseconds) at which edge LSRs can receive BFD periodic control packets. If this value is greater than the value of Acceptable Min. Asynchronous TX interval received from the other edge LSR, such an edge LSR MUST adopt the interval expressed in this Acceptable Min. Asynchronous RX interval.
如果在BFD配置子TLV中清除了S（对称）标志，则表示边缘LSR可以接收BFD周期性控制数据包的最小时间间隔（以微秒为单位）。如果该值大于从另一个边缘LSR接收的可接受最小异步发送间隔的值，则该边缘LSR必须采用该可接受最小异步接收间隔中表示的间隔。
Required Echo TX Interval: The minimum interval (in microseconds) between received BFD Echo packets that this system is capable of supporting, less any jitter applied by the sender as described in Section 6.8.9 of [RFC5880]. This value is also an indication for the receiving system of the minimum interval between transmitted BFD Echo packets. If this value is zero, the transmitting system does not support the receipt of BFD Echo packets. If the receiving system cannot support this value, the "Unsupported BFD TX Echo rate interval" error MUST be generated. By default, the value is set to 0.
所需回波发送间隔：本系统能够支持的接收BFD回波数据包之间的最小间隔（微秒），减去[RFC5880]第6.8.9节所述发送方施加的任何抖动。该值也是接收系统发送BFD回波数据包之间最小间隔的指示。如果该值为零，则传输系统不支持接收BFD回波数据包。如果接收系统无法支持此值，则必须生成“不支持的BFD TX回波速率间隔”错误。默认情况下，该值设置为0。
The "BFD Authentication sub-TLV" is carried as a sub-TLV of the "BFD Configuration sub-TLV" and is depicted in Figure 6.
“BFD认证子TLV”作为“BFD配置子TLV”的子TLV携带，如图6所示。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFD Auth. Sub-type (103) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Auth Type | Auth Key ID | Reserved (0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFD Auth. Sub-type (103) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Auth Type | Auth Key ID | Reserved (0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: BFD Authentication Sub-TLV Format
图6:BFD认证子TLV格式
Sub-type: Indicates a new sub-type, the BFD Authentication sub-TLV (value 103).
子类型：表示一个新的子类型，BFD身份验证子TLV（值103）。
Length: Indicates the length of the Value field in octets (4).
长度：以八位字节（4）表示值字段的长度。
Auth Type: Indicates which type of authentication to use. The same values as are defined in Section 4.1 of [RFC5880] are used. Simple Password SHOULD NOT be used if other authentication types are available.
身份验证类型：指示要使用的身份验证类型。使用[RFC5880]第4.1节中定义的相同值。如果其他身份验证类型可用，则不应使用简单密码。
Auth Key ID: Indicates which authentication key or password (depending on Auth Type) should be used. How the key exchange is performed is out of scope of this document. If the egress LSR does not support this Auth Key ID, an "OAM Problem/Mismatch of BFD Authentication Key ID" error MUST be generated.
身份验证密钥ID：指示应使用哪个身份验证密钥或密码（取决于身份验证类型）。如何执行密钥交换超出了本文档的范围。如果出口LSR不支持此身份验证密钥ID，则必须生成“OAM问题/BFD身份验证密钥ID不匹配”错误。
Reserved: Reserved for future specification; set to 0 on transmission and ignored when received.
预留：预留供将来规范使用；传输时设置为0，接收时忽略。
An implementation MAY change the mode of authentication if an operator re-evaluates the security situation in and around the administrative domain. If the BFD Authentication sub-TLV is used for a BFD session in Up state, then the Sender of the MPLS LSP Echo Request SHOULD ensure that old and new modes of authentication, i.e., a combination of Auth.Type and Auth. Key ID, are used to send and receive BFD control packets, until the Sender can confirm that its peer has switched to the new authentication.
如果操作员重新评估管理域内及其周围的安全状况，则实现可能会更改身份验证模式。如果BFD身份验证子TLV用于处于启动状态的BFD会话，则MPLS LSP回显请求的发送方应确保新旧身份验证模式，即身份验证类型和身份验证的组合。密钥ID用于发送和接收BFD控制数据包，直到发送方确认其对等方已切换到新的身份验证。
The Traffic Class sub-TLV is carried as a sub-TLV of the "BFD Configuration sub-TLV" and "Fault Management Signal Sub-TLV" (Section 2.2.9) and is depicted in Figure 7.
交通等级子TLV作为“BFD配置子TLV”和“故障管理信号子TLV”（第2.2.9节）的子TLV携带，如图7所示。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Traffic Class Sub-type (104) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TC | Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Traffic Class Sub-type (104) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TC | Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: Traffic Class Sub-TLV Format
图7：交通等级子TLV格式
Sub-type: Indicates a new sub-type, the "Traffic Class sub-TLV" (value 104).
子类型：表示一个新的子类型，“交通等级子TLV”（值104）。
Length: Indicates the length of the Value field in octets (4).
长度：以八位字节（4）表示值字段的长度。
TC: Identifies the Traffic Class (TC) [RFC5462] for periodic continuity monitoring messages or packets with fault management information.
TC：识别定期连续性监测消息或包含故障管理信息的数据包的流量等级（TC）[RFC5462]。
If the TC sub-TLV is present, then the sender of any periodic continuity monitoring messages or packets with fault management information on the LSP, with a Forwarding Equivalence Class (FEC) that corresponds to the FEC for which fault detection is being performed, MUST use the value contained in the TC field of the sub-TLV as the value of the TC field in the top label stack entry of the MPLS label stack. If the TC sub-TLV is absent from either "BFD Configuration sub-TLV" or "Fault Management Signal sub-TLV", then selection of the TC value is a local decision.
如果存在TC子TLV，则任何定期连续性监视消息或在LSP上具有故障管理信息的分组的发送方，具有对应于正在执行故障检测的FEC的转发等价类（FEC），必须使用子TLV的TC字段中包含的值作为MPLS标签堆栈顶部标签堆栈项中TC字段的值。如果“BFD配置子TLV”或“故障管理信号子TLV”中没有TC子TLV，则TC值的选择是本地决定。
If the MPLS OAM Functions TLV has any of the L (Loss), D (Delay), and T (Throughput) flags set, the Performance Monitoring sub-TLV MUST be present. Failure to include the correct sub-TLVs MUST result in an "OAM Problem/PM Configuration Error" being generated.
如果MPLS OAM功能TLV设置了L（丢失）、D（延迟）和T（吞吐量）标志中的任何一个，则必须存在性能监视子TLV。未能包含正确的子TLV必须导致生成“OAM问题/PM配置错误”。
The Performance Monitoring sub-TLV provides the configuration information mentioned in Section 7 of [RFC6374]. It includes support for the configuration of quality thresholds and, as described in [RFC6374]:
性能监控子TLV提供[RFC6374]第7节中提到的配置信息。它包括对质量阈值配置的支持，如[RFC6374]所述：
...the crossing of which will trigger warnings or alarms, and result in reporting and exception notification will be integrated into the system-wide network management and reporting framework.
…交叉将触发警告或警报，并导致报告和异常通知，将集成到全系统网络管理和报告框架中。
In case the values need to be different than the default ones, the Performance Monitoring sub-TLV MAY include the following sub-TLVs:
如果值需要不同于默认值，则性能监控子TLV可包括以下子TLV：
o PM Loss sub-TLV, if the L flag is set in the MPLS OAM Functions TLV;
o 如果在MPLS OAM功能TLV中设置了L标志，则PM丢失子TLV；
o PM Delay sub-TLV, if the D flag is set in the MPLS OAM Functions TLV.
o 如果在MPLS OAM功能TLV中设置了D标志，则为PM Delay sub TLV。
The Performance Monitoring sub-TLV depicted in Figure 8 is carried as a sub-TLV of the MPLS OAM Functions TLV.
图8中描述的性能监视子TLV作为MPLS OAM功能TLV的子TLV携带。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Perf. Monitoring Sub-type (200)| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Configuration Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Perf. Monitoring Sub-type (200)| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Configuration Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: Performance Monitoring Sub-TLV Format
图8：性能监控子TLV格式
Sub-type: Indicates a new sub-type, the Performance Monitoring sub-TLV (value 200).
子类型：表示新的子类型，即性能监控子TLV（值200）。
Length: Indicates the length of the Value field in octets, including PM Configuration Flags and optional sub-TLVs.
长度：以八位字节表示值字段的长度，包括PM配置标志和可选的子TLV。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|D|L|J|Y|K|C| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|D|L|J|Y|K|C| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: PM Configuration Flags Format
图9:PM配置标志格式
The PM Configuration Flags format is presented in Figure 9. For the specific function description, please refer to [RFC6374]:
PM配置标志格式如图9所示。具体功能描述请参见[RFC6374]：
D: Delay inferred/direct (0=INFERRED, 1=DIRECT). If the egress LSR does not support the specified mode, an "OAM Problem/ Unsupported Delay Mode" error MUST be generated.
D：推断/直接延迟（0=推断，1=直接）。如果出口LSR不支持指定模式，则必须生成“OAM问题/不支持的延迟模式”错误。
L: Loss inferred/direct (0=INFERRED, 1=DIRECT). If the egress LSR does not support the specified mode, an "OAM Problem/ Unsupported Loss Mode" error MUST be generated.
L：推断/直接损失（0=推断，1=直接）。如果出口LSR不支持指定模式，则必须生成“OAM问题/不支持的丢失模式”错误。
J: Delay variation/jitter (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not support Delay variation measurements and the J flag is set, an "OAM Problem/Delay variation unsupported" error MUST be generated.
J：延迟变化/抖动（1=激活，0=未激活）。如果出口LSR不支持延迟变化测量，并且设置了J标志，则必须生成“OAM问题/延迟变化不支持”错误。
Y: Dyadic (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not support Dyadic mode and the Y flag is set, an "OAM Problem/ Dyadic mode unsupported" error MUST be generated.
Y：并矢（1=激活，0=未激活）。如果出口LSR不支持并矢模式且设置了Y标志，则必须生成“OAM问题/并矢模式不支持”错误。
K: Loopback (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not support Loopback mode and the K flag is set, an "OAM Problem/ Loopback mode unsupported" error MUST be generated.
K：环回（1=活动，0=不活动）。如果出口LSR不支持环回模式，并且设置了K标志，则必须生成“OAM问题/环回模式不支持”错误。
C: Combined (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not support Combined mode and the C flag is set, an "OAM Problem/ Combined mode unsupported" error MUST be generated.
C：组合（1=激活，0=未激活）。如果出口LSR不支持组合模式且设置了C标志，则必须生成“OAM问题/组合模式不支持”错误。
Reserved: Reserved for future specification; set to 0 on transmission and ignored when received.
预留：预留供将来规范使用；传输时设置为0，接收时忽略。
The PM Loss Measurement sub-TLV depicted in Figure 10 is carried as a sub-TLV of the Performance Monitoring sub-TLV.
图10所示的PM损耗测量子TLV作为性能监测子TLV的子TLV进行。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Loss Sub-type (201) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OTF |T|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Test Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Loss Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Loss Sub-type (201) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OTF |T|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Test Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Loss Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: PM Loss Measurement Sub-TLV Format
图10:PM损耗测量子TLV格式
Sub-type: Indicates a new sub-type, the PM Loss Measurement sub-TLV (value 201).
子类型：表示一个新的子类型，即PM损耗测量子TLV（值201）。
Length: Indicates the length of the Value field in octets (16).
长度：以八位字节（16）表示值字段的长度。
OTF: Origin Timestamp Format of the Origin Timestamp field described in [RFC6374]. By default, it is set to IEEE 1588 version 1. If the egress LSR cannot support this value, an "OAM Problem/Unsupported Timestamp Format" error MUST be generated.
OTF:[RFC6374]中描述的原点时间戳字段的原点时间戳格式。默认情况下，它设置为IEEE 1588版本1。如果出口LSR不能支持此值，则必须生成“OAM问题/不支持的时间戳格式”错误。
Configuration Flags, please refer to [RFC6374] for further details:
配置标志，请参考[RFC6374]了解更多详细信息：
T: Traffic-class-specific measurement indicator. Set to 1 when the measurement operation is scoped to packets of a particular traffic class (Differentiated Services Code Point value), and 0 otherwise. When set to 1, the Differentiated Services (DS) field of the message indicates the measured traffic class. By default, it is set to 1.
T：交通等级特定测量指标。当测量操作的范围限定为特定流量类别（区分服务代码点值）的数据包时，设置为1，否则设置为0。当设置为1时，消息的区分服务（DS）字段指示测量的流量类别。默认情况下，它设置为1。
B: Octet (byte) count. When set to 1, indicates that the Counter 1-4 fields represent octet counts. When set to 0, indicates that the Counter 1-4 fields represent packet counts. By default, it is set to 0.
八位字节（字节）计数。设置为1时，表示计数器1-4字段表示八位字节计数。设置为0时，表示计数器1-4字段表示数据包计数。默认情况下，它设置为0。
Reserved: Reserved for future specification; set to 0 on transmission and ignored when received.
预留：预留供将来规范使用；传输时设置为0，接收时忽略。
Measurement Interval: The time interval (in milliseconds) at which Loss Measurement query messages MUST be sent on both directions. If the edge LSR receiving the Path message cannot support such a value, it SHOULD reply with a higher interval. By default, it is set to (100) as per [RFC6375].
度量间隔：必须在两个方向上发送损失度量查询消息的时间间隔（以毫秒为单位）。如果接收路径消息的边缘LSR不能支持这样的值，它应该以更高的间隔进行响应。默认情况下，根据[RFC6375]将其设置为（100）。
Test Interval: Test messages interval in milliseconds as described in [RFC6374]. By default, it is set to (10) as per [RFC6375].
测试间隔：测试消息间隔（毫秒），如[RFC6374]所述。默认情况下，根据[RFC6375]将其设置为（10）。
Loss Threshold: The threshold value of measured lost packets per measurement over which action(s) SHOULD be triggered.
丢失阈值：每次测量中测量到的丢失数据包的阈值，应在该阈值上触发操作。
The "PM Delay Measurement sub-TLV" depicted in Figure 11 is carried as a sub-TLV of the Performance Monitoring sub-TLV.
图11中描述的“PM延迟测量子TLV”作为性能监控子TLV的子TLV携带。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Delay Sub-type (202) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OTF |T|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Test Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Delay Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Delay Sub-type (202) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OTF |T|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Test Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Delay Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 11: PM Delay Measurement Sub-TLV Format
图11:PM延迟测量子TLV格式
Sub-type: Indicates a new sub-type, the "PM Delay Measurement sub-TLV" (value 202).
子类型：表示一个新的子类型，“PM延迟测量子TLV”（值202）。
Length: Indicates the length of the Value field in octets (16).
长度：以八位字节（16）表示值字段的长度。
OTF: Origin Timestamp Format of the Origin Timestamp field described in [RFC6374]. By default, it is set to IEEE 1588 version 1. If the egress LSR cannot support this value, an "OAM Problem/Unsupported Timestamp Format" error MUST be generated.
OTF:[RFC6374]中描述的原点时间戳字段的原点时间戳格式。默认情况下，它设置为IEEE 1588版本1。如果出口LSR不能支持此值，则必须生成“OAM问题/不支持的时间戳格式”错误。
Configuration Flags, please refer to [RFC6374] for further details:
配置标志，请参考[RFC6374]了解更多详细信息：
T: Traffic-class-specific measurement indicator. Set to 1 when the measurement operation is scoped to packets of a particular traffic class (Differentiated Services Code Point value), and 0 otherwise. When set to 1, the DS field of the message indicates the measured traffic class. By default, it is set to 1.
T：交通等级特定测量指标。当测量操作的范围限定为特定流量类别（区分服务代码点值）的数据包时，设置为1，否则设置为0。当设置为1时，消息的DS字段指示测量的流量等级。默认情况下，它设置为1。
B: Octet (byte) count. When set to 1, indicates that the Counter 1-4 fields represent octet counts. When set to 0, indicates that the Counter 1-4 fields represent packet counts. By default, it is set to 0.
八位字节（字节）计数。设置为1时，表示计数器1-4字段表示八位字节计数。设置为0时，表示计数器1-4字段表示数据包计数。默认情况下，它设置为0。
Reserved: Reserved for future specification; set to 0 on transmission and ignored when received.
预留：预留供将来规范使用；传输时设置为0，接收时忽略。
Measurement Interval: The time interval (in milliseconds) at which Delay Measurement query messages MUST be sent on both directions. If the edge LSR receiving the Path message cannot support such a value, it can reply with a higher interval. By default, it is set to (1000) as per [RFC6375].
测量间隔：必须在两个方向上发送延迟测量查询消息的时间间隔（毫秒）。如果接收路径消息的边缘LSR不能支持这样的值，它可以以更高的间隔进行回复。默认情况下，根据[RFC6375]将其设置为（1000）。
Test Interval: Test messages interval (in milliseconds) as described in [RFC6374]. By default, it is set to (10) as per [RFC6375].
测试间隔：测试消息间隔（毫秒），如[RFC6374]中所述。默认情况下，根据[RFC6375]将其设置为（10）。
Delay Threshold: The threshold value of measured two-way delay (in milliseconds) over which action(s) SHOULD be triggered.
Delay Threshold（延迟阈值）：应触发操作的测量双向延迟（以毫秒为单位）的阈值。
The FMS sub-TLV depicted in Figure 12 is carried as a sub-TLV of the MPLS OAM Configuration sub-TLV. When both working and protection paths are configured, both LSPs SHOULD be configured with identical settings of the E flag, T flag, and the refresh timer. An implementation MAY configure the working and protection LSPs with different settings of these fields in case of 1:N protection.
图12中所示的FMS子TLV作为MPLS OAM配置子TLV的子TLV携带。配置工作和保护路径时，两个LSP应配置相同的E标志、T标志和刷新计时器设置。在1:N保护的情况下，实现可以使用这些字段的不同设置配置工作和保护LSP。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FMS Sub-type (300) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|E|S|T| Reserved | Refresh Timer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FMS Sub-type (300) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|E|S|T| Reserved | Refresh Timer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 12: Fault Management Signal Sub-TLV Format
图12：故障管理信号子TLV格式
Sub-type: Indicates a new sub-type, the FMS sub-TLV (value 300).
子类型：表示一个新的子类型，FMS子TLV（值300）。
Length: Indicates the length of the Value field in octets.
长度：以八位字节表示值字段的长度。
FMS Flags are used to enable the FMS Flags at end point MEPs and the Server MEPs of the links over which the LSP is forwarded. In this document, only the S flag pertains to Server MEPs.
FMS标志用于启用LSP转发链路的端点MEP和服务器MEP处的FMS标志。在本文档中，只有S标志与服务器MEP相关。
The following flags are defined:
定义了以下标志：
E: Enable Alarm Indication Signal (AIS) and Lock Report (LKR) signaling as described in [RFC6427]. Default value is 1 (enabled). If the egress MEP does not support FMS Flag generation, an "OAM Problem/Fault management signaling unsupported" error MUST be generated.
E：如[RFC6427]所述，启用报警指示信号（AIS）和锁定报告（LKR）信号。默认值为1（已启用）。如果出口MEP不支持FMS标志生成，则必须生成“OAM问题/故障管理信令不支持”错误。
S: Indicate to a Server MEP that it should transmit AIS and LKR signals on the client LSP. Default value is 0 (disabled). If a Server MEP that is capable of generating FMS messages is, for some reason, unable to do so for the LSP being signaled, an "OAM Problem/Unable to create fault management association" error MUST be generated.
S：向服务器MEP指示它应在客户端LSP上传输AIS和LKR信号。默认值为0（已禁用）。如果能够生成FMS消息的服务器MEP由于某种原因无法对发出信号的LSP执行此操作，则必须生成“OAM问题/无法创建故障管理关联”错误。
T: Set timer value, enabled the configuration of a specific timer value. Default value is 0 (disabled).
T：设置定时器值，启用特定定时器值的配置。默认值为0（已禁用）。
Reserved: Bits 4-16 that follow the FMS Flags are reserved for future allocation. These bits MUST be set to 0 on transmit and ignored on receipt if not allocated.
保留：FMS标志后面的位4-16保留供将来分配。这些位在传输时必须设置为0，如果未分配，则在接收时忽略。
Refresh Timer: Indicates the refresh timer of fault indication messages, in seconds. The value MUST be between 1 to 20 seconds as specified for the Refresh Timer field in [RFC6427]. If the edge LSR receiving the Path message cannot support the value, it SHOULD reply with a higher timer value.
刷新计时器：表示故障指示消息的刷新计时器，以秒为单位。该值必须在[RFC6427]中为刷新计时器字段指定的1到20秒之间。如果接收路径消息的边缘LSR不支持该值，则应使用更高的计时器值进行响应。
FMS sub-TLV MAY include Traffic Class sub-TLV (Section 2.2.5). If the TC sub-TLV is present, the value of the TC field MUST be used as the value of the TC field of an MPLS label stack entry for FMS messages. If the TC sub-TLV is absent, then selection of the TC value is a local decision.
FMS子TLV可包括交通等级子TLV（第2.2.5节）。如果存在TC子TLV，则TC字段的值必须用作FMS消息的MPLS标签堆栈条目的TC字段值。如果没有TC子TLV，则TC值的选择是本地决定。
The Source MEP-ID sub-TLV depicted in Figure 13 is carried as a sub-TLV of the MPLS OAM Functions TLV.
图13所示的源MEP-ID子TLV作为MPLS OAM功能TLV的子TLV携带。
Note that support of ITU IDs is out of scope.
请注意，对ITU IDs的支持超出了范围。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source MEP-ID Sub-type (400) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Node ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tunnel ID | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source MEP-ID Sub-type (400) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Node ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tunnel ID | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13: Source MEP-ID Sub-TLV Format
图13：源MEP-ID子TLV格式
Sub-type: Indicates a new sub-type, the Source MEP-ID sub-TLV (value 400).
子类型：表示新的子类型，即源MEP-ID子TLV（值400）。
Length: Indicates the length of the Value field in octets (8).
长度：以八位字节（8）表示值字段的长度。
Source Node ID: 32-bit node identifier as defined in [RFC6370].
源节点ID:[RFC6370]中定义的32位节点标识符。
Tunnel ID: A 16-bit unsigned integer unique to the node as defined in [RFC6370].
隧道ID:[RFC6370]中定义的节点唯一的16位无符号整数。
LSP ID: A 16-bit unsigned integer unique within the Tunnel_ID as defined in [RFC6370].
LSP ID:[RFC6370]中定义的隧道ID内唯一的16位无符号整数。
This is the summary of Return Codes [RFC4379] defined in this document:
这是本文档中定义的返回代码[RFC4379]的摘要：
o If an egress LSR does not support the specified BFD version, an error MUST be generated: "OAM Problem/Unsupported BFD Version".
o 如果出口LSR不支持指定的BFD版本，则必须生成错误：“OAM问题/不支持的BFD版本”。
o If an egress LSR does not support the specified BFD Encapsulation format, an error MUST be generated: "OAM Problem/Unsupported BFD Encapsulation format".
o 如果出口LSR不支持指定的BFD封装格式，则必须生成错误：“OAM问题/不支持的BFD封装格式”。
o If an egress LSR does not support BFD Authentication, and it is requested, an error MUST be generated: "OAM Problem/BFD Authentication unsupported".
o 如果出口LSR不支持BFD身份验证，则必须生成错误：“OAM问题/BFD身份验证不受支持”。
o If an egress LSR does not support the specified BFD Authentication Type, an error MUST be generated: "OAM Problem/Unsupported BFD Authentication Type".
o 如果出口LSR不支持指定的BFD身份验证类型，则必须生成错误：“OAM问题/不支持的BFD身份验证类型”。
o If an egress LSR is not able to use the specified Authentication Key ID, an error MUST be generated: "OAM Problem/Mismatch of BFD Authentication Key ID".
o 如果出口LSR无法使用指定的身份验证密钥ID，则必须生成错误：“OAM问题/BFD身份验证密钥ID不匹配”。
o If PM flags in MPLS OAM Functions TLV don't have corresponding PM sub-TLVs present, an error MUST be generated: "OAM Problem/PM Configuration Error".
o 如果MPLS OAM函数TLV中的PM标志没有相应的PM子TLV，则必须生成错误：“OAM问题/PM配置错误”。
o If an egress LSR does not support the specified Timestamp Format, an error MUST be generated: "OAM Problem/Unsupported Timestamp Format".
o 如果出口LSR不支持指定的时间戳格式，则必须生成错误：“OAM问题/不支持的时间戳格式”。
o If an egress LSR does not support specified Delay mode, an "OAM Problem/Unsupported Delay Mode" error MUST be generated.
o 如果出口LSR不支持指定的延迟模式，则必须生成“OAM问题/不支持的延迟模式”错误。
o If an egress LSR does not support specified Loss mode, an "OAM Problem/Unsupported Loss Mode" error MUST be generated.
o 如果出口LSR不支持指定的丢失模式，则必须生成“OAM问题/不支持的丢失模式”错误。
o If an egress LSR does not support Delay variation measurements, and it is requested, an "OAM Problem/Delay variation unsupported" error MUST be generated.
o 如果出口LSR不支持延迟变化测量，并且被请求，则必须生成“OAM问题/延迟变化不支持”错误。
o If an egress LSR does not support Dyadic mode, and it is requested, an "OAM Problem/Dyadic mode unsupported" error MUST be generated.
o 如果出口LSR不支持并进模式，并且被请求，则必须生成“OAM问题/并进模式不支持”错误。
o If an egress LSR does not support Loopback mode, and it is requested, an "OAM Problem/Loopback mode unsupported" error MUST be generated.
o 如果出口LSR不支持环回模式，并且被请求，则必须生成“OAM问题/环回模式不支持”错误。
o If an egress LSR does not support Combined mode, and it is requested, an "OAM Problem/Combined mode unsupported" error MUST be generated.
o 如果出口LSR不支持组合模式，并且被请求，则必须生成“OAM问题/组合模式不支持”错误。
o If an egress LSR does not support Fault Monitoring Signals, and it is requested, an "OAM Problem/Fault management signaling unsupported" error MUST be generated.
o 如果出口LSR不支持故障监测信号，并且被请求，则必须生成“OAM问题/故障管理信号不支持”错误。
o If an intermediate Server MEP supports Fault Monitoring Signals, but is unable to create an association, when requested to do so, an "OAM Problem/Unable to create fault management association" error MUST be generated.
o 如果中间服务器MEP支持故障监视信号，但无法创建关联，则在请求创建关联时，必须生成“OAM问题/无法创建故障管理关联”错误。
Ingress LSR MAY combine multiple MPLS OAM configuration TLVs and sub-TLVs into single MPLS echo request. In case an egress LSR doesn't support any of the requested modes, it MUST set the return code to report the first unsupported mode in the list of TLVs and sub-TLVs. And if any of the requested OAM configuration is not supported, the egress LSR SHOULD NOT process OAM Configuration TLVs and sub-TLVs listed in the MPLS echo request.
入口LSR可以将多个MPLS OAM配置TLV和子TLV组合成单个MPLS回波请求。如果出口LSR不支持任何请求的模式，它必须设置返回代码以报告TLV和子TLV列表中第一个不支持的模式。并且如果所请求的任何OAM配置不受支持，则出口LSR不应处理MPLS echo请求中列出的OAM配置tlv和子tlv。
IANA maintains the "Multi-Protocol Label Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters" registry and, within that registry, a subregistry for TLVs and sub-TLVs.
IANA维护“多协议标签交换（MPLS）标签交换路径（LSP）Ping参数”注册表以及该注册表中TLV和子TLV的子注册表。
IANA has allocated a new MPLS OAM Functions TLV from the Standards Action [RFC5226] range (0-16383) and sub-TLVs as follows from subregistry presented in Table 1, called "Sub-TLVs for TLV Type 27".
IANA已从标准行动[RFC5226]范围（0-16383）分配了一个新的MPLS OAM功能TLV，并从表1所示的子区分配了一个称为“TLV类型27的子TLV”的子TLV，如下所示。
Registration procedures for Sub-TLVs from ranges 0-16383 and 32768-49161 are by Standards Action. Ranges 16384-31743 and 49162-64511 are through Specification Required (Experimental RFC Needed).
范围为0-16383和32768-49161的次级TLV的注册程序由标准行动部规定。范围16384-31743和49162-64511符合规范要求（需要实验RFC）。
+------+----------+---------------------------------+---------------+
| Type | Sub-type | Value Field | Reference |
+------+----------+---------------------------------+---------------+
| 27 | | MPLS OAM Functions | This document |
| | 100 | BFD Configuration | This document |
| | 101 | BFD Local Discriminator | This document |
| | 102 | BFD Negotiation Timer | This document |
| | | Parameters | |
| | 103 | BFD Authentication | This document |
| | 104 | Traffic Class | This document |
| | 200 | Performance Monitoring | This document |
| | 201 | PM Loss Measurement | This document |
| | 202 | PM Delay Measurement | This document |
| | 300 | Fault Management Signal | This document |
| | 400 | Source MEP-ID | This document |
+------+----------+---------------------------------+---------------+
+------+----------+---------------------------------+---------------+
| Type | Sub-type | Value Field | Reference |
+------+----------+---------------------------------+---------------+
| 27 | | MPLS OAM Functions | This document |
| | 100 | BFD Configuration | This document |
| | 101 | BFD Local Discriminator | This document |
| | 102 | BFD Negotiation Timer | This document |
| | | Parameters | |
| | 103 | BFD Authentication | This document |
| | 104 | Traffic Class | This document |
| | 200 | Performance Monitoring | This document |
| | 201 | PM Loss Measurement | This document |
| | 202 | PM Delay Measurement | This document |
| | 300 | Fault Management Signal | This document |
| | 400 | Source MEP-ID | This document |
+------+----------+---------------------------------+---------------+
Table 1: IANA TLV Type Allocation
表1:IANA TLV类型分配
IANA has created a new registry called the "MPLS OAM Function Flags" registry. Assignments of bit positions 0 through 31 are via Standards Action. The new registry is to be populated as follows.
IANA创建了一个名为“MPLS OAM函数标志”的新注册表。位位置0到31的分配通过标准动作进行。新注册表将按如下方式填充。
+------------+--------------------+---------------------------------+
| Bit | MPLS OAM Function | Description |
| Position | Flag | |
+------------+--------------------+---------------------------------+
| 0 | C | Continuity Check (CC) |
| 1 | V | Connectivity Verification (CV) |
| 2 | F | Fault Management Signal (FMS) |
| 3 | L | Performance Monitoring/Loss |
| | | (PM/Loss) |
| 4 | D | Performance Monitoring/Delay |
| | | (PM/Delay) |
| 5 | T | Throughput Measurement |
| 6-30 | | Unassigned (Must be zero) |
| 31 | | Reserved |
+------------+--------------------+---------------------------------+
+------------+--------------------+---------------------------------+
| Bit | MPLS OAM Function | Description |
| Position | Flag | |
+------------+--------------------+---------------------------------+
| 0 | C | Continuity Check (CC) |
| 1 | V | Connectivity Verification (CV) |
| 2 | F | Fault Management Signal (FMS) |
| 3 | L | Performance Monitoring/Loss |
| | | (PM/Loss) |
| 4 | D | Performance Monitoring/Delay |
| | | (PM/Delay) |
| 5 | T | Throughput Measurement |
| 6-30 | | Unassigned (Must be zero) |
| 31 | | Reserved |
+------------+--------------------+---------------------------------+
Table 2: MPLS OAM Function Flags
表2:MPLS OAM功能标志
IANA maintains a registry "Multi-Protocol Label Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters", and within that registry a subregistry "Return Codes".
IANA维护一个注册表“多协议标签交换（MPLS）标签交换路径（LSP）Ping参数”，并在该注册表中维护一个子区域“返回代码”。
IANA has assigned new Return Codes from the Standards Action range (0-191) as follows:
IANA从标准行动范围（0-191）中分配了新的返回代码，如下所示：
+----------------+--------------------------------------+-----------+
| Error Value | Description | Reference |
| Sub-codes | | |
+----------------+--------------------------------------+-----------+
| 21 | OAM Problem/Unsupported BFD Version | This |
| | | document |
| 22 | OAM Problem/Unsupported BFD | This |
| | Encapsulation format | document |
| 23 | OAM Problem/Unsupported BFD | This |
| | Authentication Type | document |
| 24 | OAM Problem/Mismatch of BFD | This |
| | Authentication Key ID | document |
| 25 | OAM Problem/Unsupported Timestamp | This |
| | Format | document |
| 26 | OAM Problem/Unsupported Delay Mode | This |
| | | document |
| 27 | OAM Problem/Unsupported Loss Mode | This |
| | | document |
| 28 | OAM Problem/Delay variation | This |
| | unsupported | document |
| 29 | OAM Problem/Dyadic mode unsupported | This |
| | | document |
| 30 | OAM Problem/Loopback mode | This |
| | unsupported | document |
| 31 | OAM Problem/Combined mode | This |
| | unsupported | document |
| 32 | OAM Problem/Fault management | This |
| | signaling unsupported | document |
| 33 | OAM Problem/Unable to create fault | This |
| | management association | document |
| 34 | OAM Problem/PM Configuration Error | This |
| | | document |
+----------------+--------------------------------------+-----------+
+----------------+--------------------------------------+-----------+
| Error Value | Description | Reference |
| Sub-codes | | |
+----------------+--------------------------------------+-----------+
| 21 | OAM Problem/Unsupported BFD Version | This |
| | | document |
| 22 | OAM Problem/Unsupported BFD | This |
| | Encapsulation format | document |
| 23 | OAM Problem/Unsupported BFD | This |
| | Authentication Type | document |
| 24 | OAM Problem/Mismatch of BFD | This |
| | Authentication Key ID | document |
| 25 | OAM Problem/Unsupported Timestamp | This |
| | Format | document |
| 26 | OAM Problem/Unsupported Delay Mode | This |
| | | document |
| 27 | OAM Problem/Unsupported Loss Mode | This |
| | | document |
| 28 | OAM Problem/Delay variation | This |
| | unsupported | document |
| 29 | OAM Problem/Dyadic mode unsupported | This |
| | | document |
| 30 | OAM Problem/Loopback mode | This |
| | unsupported | document |
| 31 | OAM Problem/Combined mode | This |
| | unsupported | document |
| 32 | OAM Problem/Fault management | This |
| | signaling unsupported | document |
| 33 | OAM Problem/Unable to create fault | This |
| | management association | document |
| 34 | OAM Problem/PM Configuration Error | This |
| | | document |
+----------------+--------------------------------------+-----------+
Table 3: IANA Return Codes Allocation
表3:IANA返回代码分配
The signaling of OAM-related parameters and the automatic establishment of OAM entities introduces additional security considerations to those discussed in [RFC4379]. In particular, a network element could be overloaded if an attacker were to request high-frequency liveliness monitoring of a large number of LSPs, targeting a single network element. Implementations must be made cognizant of available OAM resources and MAY refuse new OAM configurations that would overload a node. Additionally, policies to manage OAM resources may be used to provide some fairness in OAM resource distribution among monitored LSPs.
OAM相关参数的信令和OAM实体的自动建立引入了[RFC4379]中讨论的额外安全注意事项。特别是，如果攻击者以单个网元为目标请求对大量LSP进行高频活动性监视，则网元可能会过载。实现必须了解可用的OAM资源，并可能拒绝会使节点过载的新OAM配置。此外，管理OAM资源的策略可用于在被监视lsp之间的OAM资源分配中提供一些公平性。
Security of OAM protocols configured with extensions to LSP Ping described in this document are discussed in [RFC5880], [RFC5884], [RFC6374], [RFC6427], and [RFC6428].
[RFC5880]、[RFC5884]、[RFC6374]、[RFC6427]和[RFC6428]中讨论了配置了LSP Ping扩展的OAM协议的安全性。
In order that the configuration of OAM functionality can be achieved securely through the techniques described in this document, security mechanisms must already be in place and operational for LSP Ping. Thus, the exchange of security parameters (such as keys) for use in securing OAM is outside the scope of this document and is assumed to use an off-line mechanism or an established secure key exchange protocol.
为了通过本文档中描述的技术安全地实现OAM功能的配置，安全机制必须已经到位并可用于LSP Ping。因此，用于保护OAM的安全参数（例如密钥）的交换不在本文档的范围内，并且假定使用离线机制或已建立的安全密钥交换协议。
Additional discussion of security for MPLS protocols can be found in [RFC5920].
有关MPLS协议安全性的更多讨论，请参见[RFC5920]。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <http://www.rfc-editor.org/info/rfc2119>.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，DOI 10.17487/RFC2119，1997年3月<http://www.rfc-editor.org/info/rfc2119>.
[RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures", RFC 4379, DOI 10.17487/RFC4379, February 2006, <http://www.rfc-editor.org/info/rfc4379>.
[RFC4379]Kompella，K.和G.Swallow，“检测多协议标签交换（MPLS）数据平面故障”，RFC 4379，DOI 10.17487/RFC4379，2006年2月<http://www.rfc-editor.org/info/rfc4379>.
[RFC5654] Niven-Jenkins, B., Ed., Brungard, D., Ed., Betts, M., Ed., Sprecher, N., and S. Ueno, "Requirements of an MPLS Transport Profile", RFC 5654, DOI 10.17487/RFC5654, September 2009, <http://www.rfc-editor.org/info/rfc5654>.
[RFC5654]Niven Jenkins，B.，Ed.，Brungard，D.，Ed.，Betts，M.，Ed.，Sprecher，N.，和S.Ueno，“MPLS传输配置文件的要求”，RFC 5654，DOI 10.17487/RFC5654，2009年9月<http://www.rfc-editor.org/info/rfc5654>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, <http://www.rfc-editor.org/info/rfc5880>.
[RFC5880]Katz，D.和D.Ward，“双向转发检测（BFD）”，RFC 5880，DOI 10.17487/RFC5880，2010年6月<http://www.rfc-editor.org/info/rfc5880>.
[RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "Bidirectional Forwarding Detection (BFD) for MPLS Label Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884, June 2010, <http://www.rfc-editor.org/info/rfc5884>.
[RFC5884]Aggarwal，R.，Kompella，K.，Nadeau，T.，和G.Swallow，“MPLS标签交换路径（LSP）的双向转发检测（BFD）”，RFC 5884，DOI 10.17487/RFC5884，2010年6月<http://www.rfc-editor.org/info/rfc5884>.
[RFC6370] Bocci, M., Swallow, G., and E. Gray, "MPLS Transport Profile (MPLS-TP) Identifiers", RFC 6370, DOI 10.17487/RFC6370, September 2011, <http://www.rfc-editor.org/info/rfc6370>.
[RFC6370]Bocci，M.，Swallow，G.和E.Gray，“MPLS传输配置文件（MPLS-TP）标识符”，RFC 6370，DOI 10.17487/RFC6370，2011年9月<http://www.rfc-editor.org/info/rfc6370>.
[RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay Measurement for MPLS Networks", RFC 6374, DOI 10.17487/RFC6374, September 2011, <http://www.rfc-editor.org/info/rfc6374>.
[RFC6374]Frost，D.和S.Bryant，“MPLS网络的数据包丢失和延迟测量”，RFC 6374，DOI 10.17487/RFC6374，2011年9月<http://www.rfc-editor.org/info/rfc6374>.
[RFC6427] Swallow, G., Ed., Fulignoli, A., Ed., Vigoureux, M., Ed., Boutros, S., and D. Ward, "MPLS Fault Management Operations, Administration, and Maintenance (OAM)", RFC 6427, DOI 10.17487/RFC6427, November 2011, <http://www.rfc-editor.org/info/rfc6427>.
[RFC6427]Swallow，G.，Ed.，Fulignoli，A.，Ed.，Vigoureux，M.，Ed.，Boutros，S.，和D.Ward，“MPLS故障管理操作、管理和维护（OAM）”，RFC 6427，DOI 10.17487/RFC6427，2011年11月<http://www.rfc-editor.org/info/rfc6427>.
[RFC6428] Allan, D., Ed., Swallow Ed., G., and J. Drake Ed., "Proactive Connectivity Verification, Continuity Check, and Remote Defect Indication for the MPLS Transport Profile", RFC 6428, DOI 10.17487/RFC6428, November 2011, <http://www.rfc-editor.org/info/rfc6428>.
[RFC6428]Allan，D.，Ed.，Swallow Ed.，G.，和J.Drake Ed.“MPLS传输配置文件的主动连接验证、连续性检查和远程缺陷指示”，RFC 6428，DOI 10.17487/RFC6428，2011年11月<http://www.rfc-editor.org/info/rfc6428>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, <http://www.rfc-editor.org/info/rfc3209>.
[RFC3209]Awduche，D.，Berger，L.，Gan，D.，Li，T.，Srinivasan，V.，和G.Swallow，“RSVP-TE：LSP隧道RSVP的扩展”，RFC 3209，DOI 10.17487/RFC3209，2001年12月<http://www.rfc-editor.org/info/rfc3209>.
[RFC5036] Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed., "LDP Specification", RFC 5036, DOI 10.17487/RFC5036, October 2007, <http://www.rfc-editor.org/info/rfc5036>.
[RFC5036]Andersson，L.，Ed.，Minei，I.，Ed.，和B.Thomas，Ed.“LDP规范”，RFC 5036，DOI 10.17487/RFC5036，2007年10月<http://www.rfc-editor.org/info/rfc5036>.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, DOI 10.17487/RFC5226, May 2008, <http://www.rfc-editor.org/info/rfc5226>.
[RFC5226]Narten，T.和H.Alvestrand，“在RFCs中编写IANA注意事项部分的指南”，BCP 26，RFC 5226，DOI 10.17487/RFC5226，2008年5月<http://www.rfc-editor.org/info/rfc5226>.
[RFC5462] Andersson, L. and R. Asati, "Multiprotocol Label Switching (MPLS) Label Stack Entry: "EXP" Field Renamed to "Traffic Class" Field", RFC 5462, DOI 10.17487/RFC5462, February 2009, <http://www.rfc-editor.org/info/rfc5462>.
[RFC5462]Andersson，L.和R.Asati，“多协议标签交换（MPLS）标签堆栈条目：“EXP”字段重命名为“流量类”字段”，RFC 5462，DOI 10.17487/RFC5462，2009年2月<http://www.rfc-editor.org/info/rfc5462>.
[RFC5860] Vigoureux, M., Ed., Ward, D., Ed., and M. Betts, Ed., "Requirements for Operations, Administration, and Maintenance (OAM) in MPLS Transport Networks", RFC 5860, DOI 10.17487/RFC5860, May 2010, <http://www.rfc-editor.org/info/rfc5860>.
[RFC5860]Vigoureux，M.，Ed.，Ward，D.，Ed.，和M.Betts，Ed.“MPLS传输网络中的操作、管理和维护（OAM）要求”，RFC 5860，DOI 10.17487/RFC5860，2010年5月<http://www.rfc-editor.org/info/rfc5860>.
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010, <http://www.rfc-editor.org/info/rfc5920>.
[RFC5920]方，L.，编辑，“MPLS和GMPLS网络的安全框架”，RFC 5920，DOI 10.17487/RFC5920，2010年7月<http://www.rfc-editor.org/info/rfc5920>.
[RFC6371] Busi, I., Ed. and D. Allan, Ed., "Operations, Administration, and Maintenance Framework for MPLS-Based Transport Networks", RFC 6371, DOI 10.17487/RFC6371, September 2011, <http://www.rfc-editor.org/info/rfc6371>.
[RFC6371]Busi，I.，Ed.和D.Allan，Ed.，“基于MPLS的传输网络的运营、管理和维护框架”，RFC 6371，DOI 10.17487/RFC63711911年9月<http://www.rfc-editor.org/info/rfc6371>.
[RFC6375] Frost, D., Ed. and S. Bryant, Ed., "A Packet Loss and Delay Measurement Profile for MPLS-Based Transport Networks", RFC 6375, DOI 10.17487/RFC6375, September 2011, <http://www.rfc-editor.org/info/rfc6375>.
[RFC6375]Frost，D.，Ed.和S.Bryant，Ed.，“基于MPLS的传输网络的数据包丢失和延迟测量模式”，RFC 6375，DOI 10.17487/RFC6375，2011年9月<http://www.rfc-editor.org/info/rfc6375>.
[RFC6669] Sprecher, N. and L. Fang, "An Overview of the Operations, Administration, and Maintenance (OAM) Toolset for MPLS-Based Transport Networks", RFC 6669, DOI 10.17487/RFC6669, July 2012, <http://www.rfc-editor.org/info/rfc6669>.
[RFC6669]Sprecher，N.和L.Fang，“基于MPLS的传输网络的操作、管理和维护（OAM）工具集概述”，RFC 6669，DOI 10.17487/RFC66692012年7月<http://www.rfc-editor.org/info/rfc6669>.
[RFC7419] Akiya, N., Binderberger, M., and G. Mirsky, "Common Interval Support in Bidirectional Forwarding Detection", RFC 7419, DOI 10.17487/RFC7419, December 2014, <http://www.rfc-editor.org/info/rfc7419>.
[RFC7419]Akiya，N.，Binderberger，M.，和G.Mirsky，“双向转发检测中的公共间隔支持”，RFC 7419，DOI 10.17487/RFC7419，2014年12月<http://www.rfc-editor.org/info/rfc7419>.
[RFC7487] Bellagamba, E., Takacs, A., Mirsky, G., Andersson, L., Skoldstrom, P., and D. Ward, "Configuration of Proactive Operations, Administration, and Maintenance (OAM) Functions for MPLS-Based Transport Networks Using RSVP-TE", RFC 7487, DOI 10.17487/RFC7487, March 2015, <http://www.rfc-editor.org/info/rfc7487>.
[RFC7487]Bellagamba，E.，Takacs，A.，Mirsky，G.，Andersson，L.，Skoldstrom，P.，和D.Ward，“使用RSVP-TE为基于MPLS的传输网络配置主动操作、管理和维护（OAM）功能”，RFC 7487，DOI 10.17487/RFC7487，2015年3月<http://www.rfc-editor.org/info/rfc7487>.
Acknowledgements
致谢
The authors would like to thank Nobo Akiya, David Allan, and Adrian Farrel for their thorough reviews and insightful comments.
作者要感谢Nobo Akiya、David Allan和Adrian Farrel的透彻评论和富有洞察力的评论。
Authors' Addresses
作者地址
Elisa Bellagamba
贝拉甘巴
Email: elisa.bellagamba@gmail.com
Email: elisa.bellagamba@gmail.com
Gregory Mirsky Ericsson
格雷戈里·米尔斯基·爱立信
Email: Gregory.Mirsky@ericsson.com
Email: Gregory.Mirsky@ericsson.com
Loa Andersson Huawei Technologies
安达信华为技术有限公司
Email: loa@mail01.huawei.com
Email: loa@mail01.huawei.com
Pontus Skoldstrom Acreo AB Electrum 236 Kista 164 40 Sweden
Pontus Skoldstrom Acreo AB Electrum 236基斯塔164 40瑞典
Phone: +46 8 6327731
Email: pontus.skoldstrom@acreo.se
Phone: +46 8 6327731
Email: pontus.skoldstrom@acreo.se
Dave Ward Cisco
戴夫·沃德·思科
Email: dward@cisco.com
Email: dward@cisco.com
John Drake Juniper
约翰德雷克杜尼珀
Email: jdrake@juniper.net
Email: jdrake@juniper.net