Internet Engineering Task Force (IETF) Y. Jiang, Ed.
Request for Comments: 8024 Y. Luo
Category: Standards Track Huawei
ISSN: 2070-1721 E. Mallette, Ed.
Charter Communications
Y. Shen
Juniper Networks
W. Cheng
China Mobile
November 2016
Internet Engineering Task Force (IETF) Y. Jiang, Ed.
Request for Comments: 8024 Y. Luo
Category: Standards Track Huawei
ISSN: 2070-1721 E. Mallette, Ed.
Charter Communications
Y. Shen
Juniper Networks
W. Cheng
China Mobile
November 2016
Multi-Chassis Passive Optical Network (MC-PON) Protection in MPLS
MPLS中的多机箱无源光网络（MC-PON）保护
Abstract
摘要
Multiprotocol Label Switching (MPLS) is being extended to the edge of operator networks including the network access nodes. Separately, network access nodes such as Passive Optical Network (PON) Optical Line Terminations (OLTs) have evolved to support first-mile access protection, where one or more physical OLTs provide first-mile diversity to the customer edge. Multihoming support is needed on the MPLS-enabled PON OLT to provide resiliency for provided services. This document describes the Multi-Chassis PON (MC-PON) protection architecture in MPLS and also specifies the Inter-Chassis Communication Protocol (ICCP) extension to support it.
多协议标签交换（MPLS）正在扩展到包括网络接入节点在内的运营商网络边缘。另外，诸如无源光网络（PON）光线路终端（olt）之类的网络接入节点已经演变为支持第一英里接入保护，其中一个或多个物理olt向客户边缘提供第一英里分集。支持MPLS的PON OLT上需要多主支持，以便为提供的服务提供弹性。本文档描述了MPLS中的多机箱PON（MC-PON）保护体系结构，并指定了支持该体系结构的机箱间通信协议（ICCP）扩展。
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 7841.
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 7841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/rfc8024.
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/rfc8024.
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 . . . . . . . . . . . . 5
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
2. ICCP Protocol Extensions . . . . . . . . . . . . . . . . . . 6
2.1. Multi-Chassis PON Application TLVs . . . . . . . . . . . 6
2.1.1. PON Connect TLV . . . . . . . . . . . . . . . . . . . 6
2.1.2. PON Disconnect TLV . . . . . . . . . . . . . . . . . 7
2.1.3. PON Configuration TLV . . . . . . . . . . . . . . . . 8
2.1.4. PON State TLV . . . . . . . . . . . . . . . . . . . . 9
3. Considerations on PON ONU Database Synchronization . . . . . 9
4. Multi-Chassis PON Application Procedures . . . . . . . . . . 10
4.1. Protection Procedure upon PON Link Failures . . . . . . . 11
4.2. Protection Procedure upon PW Failures . . . . . . . . . . 12
4.3. Protection Procedure upon the Working OLT Failure . . . . 12
4.4. Protection Procedure for a Dual-Homing PE . . . . . . . . 12
5. Security Considerations . . . . . . . . . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Normative References . . . . . . . . . . . . . . . . . . 14
7.2. Informative References . . . . . . . . . . . . . . . . . 14
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 15
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions Used in This Document . . . . . . . . . . . . 5
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
2. ICCP Protocol Extensions . . . . . . . . . . . . . . . . . . 6
2.1. Multi-Chassis PON Application TLVs . . . . . . . . . . . 6
2.1.1. PON Connect TLV . . . . . . . . . . . . . . . . . . . 6
2.1.2. PON Disconnect TLV . . . . . . . . . . . . . . . . . 7
2.1.3. PON Configuration TLV . . . . . . . . . . . . . . . . 8
2.1.4. PON State TLV . . . . . . . . . . . . . . . . . . . . 9
3. Considerations on PON ONU Database Synchronization . . . . . 9
4. Multi-Chassis PON Application Procedures . . . . . . . . . . 10
4.1. Protection Procedure upon PON Link Failures . . . . . . . 11
4.2. Protection Procedure upon PW Failures . . . . . . . . . . 12
4.3. Protection Procedure upon the Working OLT Failure . . . . 12
4.4. Protection Procedure for a Dual-Homing PE . . . . . . . . 12
5. Security Considerations . . . . . . . . . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Normative References . . . . . . . . . . . . . . . . . . 14
7.2. Informative References . . . . . . . . . . . . . . . . . 14
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 15
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
Multiprotocol Label Switching (MPLS) is being extended to the edge of operator networks, as is described in the multi-segment pseudowires (PWs) with Passive Optical Network (PON) access use case [RFC6456]. Combining MPLS with Optical Line Termination (OLT) access further facilitates a low-cost, multi-service convergence.
多协议标签交换（MPLS）正在扩展到运营商网络的边缘，如带无源光网络（PON）接入的多段伪线（PWs）用例[RFC6456]所述。将MPLS与光线路终端（OLT）接入相结合，进一步促进了低成本、多业务的融合。
Tens of millions of Fiber-to-the-x (FTTx) (x = H for home, P for premises, C for curb) lines have been deployed over the years, with many of those lines being some PON variant. PON provides operators a cost-effective solution for delivering high bandwidth (1 Gbps or even 10 Gbps) to a dozen or more subscribers simultaneously.
多年来，已经部署了数千万条光纤到x（FTTx）（x=H代表家庭，P代表房屋，C代表路边）线路，其中许多线路是某种PON变体。PON为运营商同时向十几个或更多用户提供高带宽（1 Gbps甚至10 Gbps）提供了一个经济高效的解决方案。
In the past, access technologies such as PON and Digital Subscriber Line (DSL) are usually used for subscribers, and no redundancy is provided in their deployment.
过去，PON和数字用户线（DSL）等接入技术通常用于用户，并且在其部署中不提供冗余。
But, with the rapid growth of mobile data traffic, more and more Long Term Evolution (LTE) small cells and Wi-Fi hotspots are deployed. PON is considered a viable low-cost backhaul solution for these mobile services. Besides its high bandwidth and scalability, PON further provides frequency and time-synchronization features, e.g., SyncE [G.8261] and IEEE 1588v2 [IEEE-1588] functionality, which can fulfill synchronization needs of mobile backhaul services.
但是，随着移动数据流量的快速增长，越来越多的长期演进（LTE）小蜂窝和Wi-Fi热点被部署。PON被认为是这些移动服务可行的低成本回程解决方案。除了高带宽和可扩展性之外，PON还提供频率和时间同步功能，例如SyncE[g.8261]和IEEE 1588v2[IEEE-1588]功能，可以满足移动回程业务的同步需求。
The Broadband Forum specifies reference architecture for mobile backhaul networks using MPLS transport in [TR-221] where PON can be the access technology.
宽带论坛在[TR-221]中规定了使用MPLS传输的移动回程网络的参考架构，其中PON可以是接入技术。
Unlike typical residential service where a single or handful of end-users hang off a single PON OLT port in a physical optical distribution network, a PON port that supports a dozen LTE small cells or Wi-Fi hotspots could be providing service to hundreds of simultaneous subscribers. Small-cell backhaul often demands the economics of a PON first mile and yet expects first-mile protection commonly available in a point-to-point access portfolio.
与典型的住宅服务不同，一个或几个终端用户在物理光分配网络中挂起一个PON OLT端口，一个支持十几个LTE小小区或Wi-Fi热点的PON端口可以同时向数百个用户提供服务。小小区回程通常需要PON第一英里的经济性，但需要点对点接入组合中常见的第一英里保护。
Some optical layer protection mechanisms, such as Trunk and Tree protection, are specified in [IEEE-1904.1] to avoid a single point of failure in the access. They are called Type B and Type C protection, respectively, in [G.983.1].
[IEEE-1904.1]中规定了一些光学层保护机制，如主干和树保护，以避免访问中出现单点故障。在[G.983.1]中，它们分别称为B型和C型保护。
Trunk protection architecture is an economical PON resiliency mechanism, where the working OLT and the working link between the working splitter port and the working OLT (i.e., the working trunk
中继保护体系结构是一种经济的PON弹性机制，其中工作OLT和工作拆分器端口与工作OLT（即工作中继）之间的工作链路
fiber) is protected by a redundant protection OLT and a redundant trunk fiber between the protection splitter port and the protection OLT; however, it only protects a portion of the optical path from OLT to Optical Network Units (ONUs). This is different from the more complex and costly Tree protection architecture where there is a working optical distribution network path from the working OLT and a complete protected optical distribution network path from the protection OLT to the ONUs. Figure 1 depicts a typical scenario of Trunk protection.
光纤）由冗余保护OLT和保护分离器端口与保护OLT之间的冗余中继光纤保护；然而，它仅保护从OLT到光网络单元（ONU）的光路的一部分。这不同于更复杂且成本更高的树型保护体系结构，在树型保护体系结构中，存在从工作OLT到工作OLT的工作光分发网络路径，以及从保护OLT到onu的完整受保护光分发网络路径。图1描述了中继保护的典型场景。
| |
|<--Optical Distribution Network->|
| |
| branch trunk +-----+
+-----+ fibers fibers | |
Base ------| | | | . OLT |
Stations ------| ONU |\ | | ,'`| A |
------| | \ V V -` +-----+
+-----+ \ .'
. \ +----------+ ,-`
+-----+ . \| -` Working
Base ------| | . | Optical |
Stations ------| ONU |---------| Splitter |
------| | . /| -, Protection
+-----+ . / +----------+ `'.,
/ `-, +-----+
+-----+ / `'.,| |
Base ------| |/ | OLT |
Stations ------| ONU | | B |
------| | +-----+
+-----+
| |
|<--Optical Distribution Network->|
| |
| branch trunk +-----+
+-----+ fibers fibers | |
Base ------| | | | . OLT |
Stations ------| ONU |\ | | ,'`| A |
------| | \ V V -` +-----+
+-----+ \ .'
. \ +----------+ ,-`
+-----+ . \| -` Working
Base ------| | . | Optical |
Stations ------| ONU |---------| Splitter |
------| | . /| -, Protection
+-----+ . / +----------+ `'.,
/ `-, +-----+
+-----+ / `'.,| |
Base ------| |/ | OLT |
Stations ------| ONU | | B |
------| | +-----+
+-----+
Figure 1: Trunk Protection Architecture in PON
图1:PON中的中继保护架构
Besides small-cell backhaul, this protection architecture can also be applicable to other services, for example, DSL and Multiple System Operator (MSO) services. In that case, an ONU in Figure 1 can play the similar role as a Digital Subscriber Line Access Multiplexer (DSLAM) or a Data Over Cable Service Interface Specification (DOCSIS) Remote Physical Layer (PHY) device [remote-phy], and it may further be attached with dozens of Customer Premises devices.
除了小小区回程之外，该保护体系结构还可以应用于其他服务，例如DSL和多系统运营商（MSO）服务。在这种情况下，图1中的ONU可以起到与数字用户线接入多路复用器（DSLAM）或有线数据服务接口规范（DOCSIS）远程物理层（PHY）设备[远程PHY]类似的作用，并且它还可以附加几十个客户场所设备。
In some deployments, it is also possible that only some ONUs need to be protected.
在某些部署中，也可能只需要保护某些ONU。
The PON architecture as depicted in Figure 1 can provide redundancy in its physical topology; however, all traffic, including link Operation Administration and Maintenance (OAM), is blocked on the
如图1所示的PON架构可以在其物理拓扑中提供冗余；但是，所有通信，包括链路操作管理和维护（OAM），都在
protection link, which frustrates end-to-end protection mechanisms such as those specified in ITU-T G.8031 [G.8031]. Therefore, some standard signaling mechanisms are needed between OLTs to exchange information, for example, PON link status, registered ONU information, and network status, so that protection and restoration can be done rapidly and reliably, especially when the OLTs also support MPLS.
保护链路，阻止端到端保护机制，如ITU-T G.8031[G.8031]中规定的保护机制。因此，OLT之间需要一些标准信令机制来交换信息，例如PON链路状态、注册的ONU信息和网络状态，以便能够快速可靠地进行保护和恢复，特别是当OLT还支持MPLS时。
ICCP [RFC7275] provides a framework for inter-chassis synchronization of state and configuration data between a set of two or more Provider Edges (PEs). Currently, ICCP only defines application-specific messages for Pseudowire Redundancy (PW-RED) and Multi-Chassis LACP (mLACP), but it can be easily extended to support PON as an Attachment Circuit (AC) redundancy.
ICCP[RFC7275]提供了一个框架，用于在一组两个或多个提供程序边缘（PE）之间进行机箱间状态和配置数据同步。目前，ICCP仅为伪线冗余（PW-RED）和多机箱LACP（mLACP）定义了特定于应用程序的消息，但它可以轻松扩展以支持PON作为连接电路（AC）冗余。
This document proposes the extension of ICCP to support multi-chassis PON protection in MPLS.
本文档建议对ICCP进行扩展，以支持MPLS中的多机箱PON保护。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
DSL: Digital Subscriber Line
数字用户线
FTTx: Fiber-to-the-x (FTTx) (x = H for home, P for premises, C for curb)
FTTx：光纤到x（FTTx）（x=H表示家庭，P表示房屋，C表示路边）
ICCP: Inter-Chassis Communication Protocol
ICCP：机箱间通信协议
OLT: Optical Line Termination
光线路终端
ONU: Optical Network Unit
光网络单元
MPLS: Multiprotocol Label Switching
多协议标签交换
PON: Passive Optical Network
无源光网络
RG: Redundancy Group
RG：冗余组
A set of MC-PON application Type-Length-Values (TLVs) are defined in the following subsections.
以下小节定义了一组MC-PON应用程序类型长度值（TLV）。
This TLV is included in the RG Connect message to signal the establishment of PON application connection.
该TLV包含在RG Connect消息中，以指示PON应用程序连接的建立。
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x200D | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol Version |A| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x200D | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol Version |A| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Sub-TLVs |
~ ~
| |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o U and F bits: both are set to 0.
o U和F位：均设置为0。
o Type: set to 0x200D for "PON Connect TLV".
o 类型：“PON连接TLV”设置为0x200D。
o Length: length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields.
o 长度：TLV的长度（以八位字节为单位），不包括U位、F位、类型和长度字段。
o Protocol Version: the version of this PON-specific protocol for the purposes of inter-chassis communication. This is set to 0x0001.
o 协议版本：用于机箱间通信的PON特定协议的版本。这设置为0x0001。
o A bit: Acknowledgement bit. It MUST be set to 1 if the sender has received a PON Connect TLV from the recipient. Otherwise, set to 0.
o 一点：一点。如果发送方从接收方接收到PON Connect TLV，则必须将其设置为1。否则，设置为0。
o Reserved: reserved for future use and MUST be set to zero.
o 保留：保留供将来使用，必须设置为零。
o Optional Sub-TLVs: there are no optional Sub-TLVs defined for this version of the protocol. The structure of optional Sub-TLVs is defined as follows:
o 可选子TLV：没有为此版本的协议定义可选子TLV。可选子TLV的结构定义如下：
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Sub-TLV Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Variable Length Value |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Sub-TLV Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Variable Length Value |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o U bit: set to 1. The unknown Sub-TLV is silently ignored.
o U位：设置为1。未知的子TLV将被静默忽略。
o F bit: set to 0.
o F位：设置为0。
o The optional Sub-TLV Type values will be allocated by IANA in a registry named "ICC RG Parameter Types" for Pseudowire Name Spaces (PWE3).
o 可选的子TLV类型值将由IANA在名为“ICC RG参数类型”的注册表中为伪线名称空间（PWE3）分配。
o Length: length of the TLV in octets, excluding the U-bit, F-bit, Type, and Length fields.
o 长度：TLV的长度（以八位字节为单位），不包括U位、F位、类型和长度字段。
This TLV is included in the RG Disconnect message to indicate that the connection for the PON application is to be terminated.
该TLV包含在RG Disconnect消息中，以指示PON应用程序的连接将被终止。
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x200E | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x200E | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o U and F bits: both are set to 0.
o U和F位：均设置为0。
o Type: set to 0x200E for "PON Disconnect TLV".
o 类型：“PON断开TLV”设置为0x200E。
o Length: length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields.
o 长度：TLV的长度（以八位字节为单位），不包括U位、F位、类型和长度字段。
o Optional Sub-TLVs: there are no optional Sub-TLVs defined for this version of the protocol.
o 可选子TLV：没有为此版本的协议定义可选子TLV。
The "PON Configuration TLV" is included in the "RG Application Data" message and announces an OLT's system parameters to other members in the same RG.
“PON配置TLV”包含在“RG应用程序数据”消息中，并向同一RG中的其他成员宣布OLT的系统参数。
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x200F | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| System ID |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| System Priority | Port 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x200F | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| System ID |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| System Priority | Port ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o U and F bits: both are set to 0.
o U和F位：均设置为0。
o Type: set to 0x200F for "PON Configuration TLV".
o 类型：“PON配置TLV”设置为0x200F。
o Length: length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields.
o 长度：TLV的长度（以八位字节为单位），不包括U位、F位、类型和长度字段。
o System ID: 8 octets encoding the System ID used by the OLT, which is the chassis Media Access Control (MAC) address. If a 6-octet System ID is used, the least significant 2 octets of the 8-octet field will be encoded as 0000.
o 系统ID：8个八位字节，编码OLT使用的系统ID，即机箱介质访问控制（MAC）地址。如果使用6个八位字节的系统ID，8个八位字节字段中最低有效的2个八位字节将被编码为0000。
o System Priority: a 2-octet value assigned by management or administration policy; the OLT with the numerically lower value of System Priority has the higher priority.
o 系统优先级：由管理或行政策略指定的2个八位组的值；系统优先级数值越低的OLT优先级越高。
o Port ID: 2-octet PON Port ID.
o 端口ID:2-octet PON端口ID。
The "PON State TLV" is included in the "RG Application Data" message and used by an OLT to report its PON states to other members in the same RG.
“PON状态TLV”包含在“RG应用程序数据”消息中，OLT使用该消息向同一RG中的其他成员报告其PON状态。
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x2010 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ROID |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local PON Port State |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Remote PON Port State |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=0x2010 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ROID |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local PON Port State |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Remote PON Port State |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o U and F bits: both are set to 0.
o U和F位：均设置为0。
o Type: set to 0x2010 for "PON State TLV".
o 类型：“PON状态TLV”设置为0x2010。
o Length: length of the TLV in octets excluding the U-bit, F-bit, Type, and Length fields.
o 长度：TLV的长度（以八位字节为单位），不包括U位、F位、类型和长度字段。
o ROID: Redundant Object ID (ROID) as defined in Section 4.3 of [RFC7275].
o ROID:[RFC7275]第4.3节中定义的冗余对象ID（ROID）。
o Local PON Port State: the status of the local PON port as determined by the sending OLT (PE). The last bit is defined as Fault indication of the PON Port associated with this PW (1 - in fault; 0 - in normal).
o 本地PON端口状态：由发送OLT（PE）确定的本地PON端口的状态。最后一位定义为与此PW相关的PON端口的故障指示（1-故障；0-正常）。
o Remote PON Port State: the status of the remote PON port as determined by the remote peer of the sending OLT (i.e., the sending PE). The last bit is defined as Fault indication of the PON Port associated with this PW (1 - in fault; 0 - in normal).
o 远程PON端口状态：由发送OLT的远程对等方（即，发送PE）确定的远程PON端口的状态。最后一位定义为与此PW相关的PON端口的故障指示（1-故障；0-正常）。
Without an effective mechanism to communicate the registered ONUs between the working and protection OLT, all registered ONUs would be de-registered and go through re-registration during a switchover, which would significantly increase protection time. To enable faster switchover capability, the working and protection OLTs need to know about the protected ONUs. To enable service continuity, a mechanism
如果没有有效的机制在工作和保护OLT之间通信已注册的ONU，则所有已注册的ONU都将被取消注册，并在切换期间进行重新注册，这将显著增加保护时间。为了实现更快的切换能力，工作和保护OLT需要了解受保护的ONU。要实现服务连续性，需要一种机制
needs to be employed such that the operational state and significant configuration data of both the protected ONU and the services provisioned to it can be distributed to the working and protection OLT.
需要采用这样的方式，即受保护ONU和向其提供的服务的操作状态和重要配置数据都可以分发到工作和保护OLT。
The specific ONU's configuration and operational data can be synchronized by some policy mechanism or provisioned in the management plane. Alternatively, said synchronization could occur by some other signaling options. Describing how to synchronize the configuration objects associated with both protected ONU as well as the services constructed to the ONU (e.g., ONU MAC address, IPv4 addresses, IPv6 addresses, VLAN identifiers, etc.) is outside of the scope of this document.
特定ONU的配置和操作数据可以通过某种策略机制进行同步，也可以在管理平面中进行配置。或者，所述同步可以通过一些其他信令选项发生。描述如何同步与受保护ONU以及构造到ONU的服务（例如，ONU MAC地址、IPv4地址、IPv6地址、VLAN标识符等）相关联的配置对象不在本文档的范围内。
Two typical MPLS protection network architectures for PON access are depicted in Figures 2 and 3 (their PON access segments are the same as in Figure 1 and thus omitted for simplification). OLTs with MPLS functionality are connected to a single PE (Figure 2) or dual-homing PEs (Figure 3), respectively, i.e., the working OLT to PE1 by a working PW and the protection OLT to PE1 or PE2 by a protection PW; thus, these devices constitute an MPLS network that provides PW transport services between ONUs and a Customer Edge (CE), and the PWs can provide protection for each other.
图2和图3描述了用于PON接入的两种典型MPLS保护网络架构（它们的PON接入段与图1相同，因此为了简化而省略）。具有MPLS功能的OLT分别连接到单个PE（图2）或双归位PE（图3），即，通过工作PW将工作OLT连接到PE1，通过保护PW将保护OLT连接到PE1或PE2；因此，这些设备构成MPLS网络，在onu和客户边缘（CE）之间提供PW传输服务，并且PW可以相互提供保护。
+-----+
| |
|OLT -,
| A | `.,
+-----+ ', PW1
`',
`., +-----+ +-----+
', | | | |
`. PE1 ------------ CE |
.'`| | | |
,-` +-----+ +-----+
.`
+-----+ .'` PW2
| | ,-`
|OLT -`
| B |
+-----+
+-----+
| |
|OLT -,
| A | `.,
+-----+ ', PW1
`',
`., +-----+ +-----+
', | | | |
`. PE1 ------------ CE |
.'`| | | |
,-` +-----+ +-----+
.`
+-----+ .'` PW2
| | ,-`
|OLT -`
| B |
+-----+
Figure 2: An MPLS Network with a Single PE
图2：具有单个PE的MPLS网络
+-----+ +-----+
| | PW1 | |
|OLT ----------------- PE1 -,
| A | | | ',
+-----+ +--/--+ ',
| `.
| `. +-----+
| `' |
| | CE |
| . |
| ,'+-----+
| ,-`
+-----+ +--\--+ ,'
| | PW2 | | .`
|OLT ----------------- PE2 -`
| B | | |
+-----+ +-----+
+-----+ +-----+
| | PW1 | |
|OLT ----------------- PE1 -,
| A | | | ',
+-----+ +--/--+ ',
| `.
| `. +-----+
| `' |
| | CE |
| . |
| ,'+-----+
| ,-`
+-----+ +--\--+ ,'
| | PW2 | | .`
|OLT ----------------- PE2 -`
| B | | |
+-----+ +-----+
Figure 3: An MPLS Network with Dual-Homing PEs
图3：具有双归宿PEs的MPLS网络
Faults may be encountered in PON access links or in the MPLS network (including the working OLT). Procedures for these cases are described in this section (it is assumed that both OLTs and PEs are working in the independent mode of PW redundancy [RFC6870]).
PON接入链路或MPLS网络（包括工作OLT）中可能会遇到故障。本节描述了这些情况下的程序（假设OLT和PEs都在PW冗余的独立模式下工作[RFC6870]）。
When a fault is detected on a working PON link, a working OLT switches to the corresponding protection PON link attached with its protection OLT, i.e., the working OLT turns off its faulty PON interface so that the protection trunk link to its protection OLT can be activated. Then, the working OLT MUST send an LDP fault notification message (i.e., with the status bit "Local AC (ingress) Receive Fault" being set) to its peer PE on the remote end of the PW. At the same time, the working OLT MUST send an ICCP message with PON State TLV with Local PON Port State being set to notify the protection OLT of the PON fault.
当在工作PON链路上检测到故障时，工作OLT切换到与其保护OLT相连的相应保护PON链路，即，工作OLT关闭其故障PON接口，以便可以激活到其保护OLT的保护中继链路。然后，工作OLT必须向PW远端的对等PE发送LDP故障通知消息（即，设置状态位“本地AC（入口）接收故障”）。同时，工作OLT必须发送一条ICCP消息，其中PON状态TLV设置为本地PON端口状态，以通知保护OLT PON故障。
Upon receiving a PON state TLV where Local PON Port State is set, a protection OLT MUST activate the protection PON link in the protection group and advertise a notification message for the protection PW with the Preferential Forwarding status bit of active to the remote PE.
在接收到设置了本地PON端口状态的PON状态TLV后，保护OLT必须激活保护组中的保护PON链路，并向远程PE播发优先转发状态位为active的保护PW通知消息。
According to [RFC6870], the remote PE(s) can match the local and remote Preferential Forwarding status and select PW2 as the new active PW over which data traffic is sent.
根据[RFC6870]，远程PE可以匹配本地和远程优先转发状态，并选择PW2作为发送数据流量的新活动PW。
Usually, MPLS networks have their own protection mechanism such as Label Switched Path (LSP) protection or Fast Reroute (FRR). But, in a link-sparse access or aggregation network where protection for a PW is impossible in its LSP layer, the following PW layer protection procedures can be enabled.
通常，MPLS网络有自己的保护机制，如标签交换路径（LSP）保护或快速重路由（FRR）。但是，在链路稀疏访问或聚合网络中，无法在其LSP层中保护PW，可以启用以下PW层保护过程。
When a fault is detected on its working PW (e.g., by Virtual Circuit Connectivity Verification (VCCV) Bidirectional Forwarding Detection (BFD)), a working OLT SHOULD turn off its associated PON interface and then send an ICCP message with PON State TLV with Local PON Port State being set to notify the protection OLT of the PON fault.
当在其工作PW上检测到故障时（例如，通过虚拟电路连接验证（VCCV）双向转发检测（BFD）），工作OLT应关闭其相关PON接口，然后发送带有PON状态TLV的ICCP消息，设置本地PON端口状态，以通知保护OLT PON故障。
Upon receiving a PON state TLV where Local PON Port State is set, the protection OLT MUST activate its PON interface to the protection trunk fiber. At the same time, the protection OLT MUST send a notification message for the protection PW with the Preferential Forwarding status bit of active to the remote PE, so that traffic can be switched to the protection PW.
在接收到设置了本地PON端口状态的PON状态TLV后，保护OLT必须激活其到保护中继光纤的PON接口。同时，保护OLT必须向远程PE发送优先转发状态位为active的保护PW通知消息，以便将通信量切换到保护PW。
As depicted in Figure 2, a service is provisioned with a working PW and a protection PW, and both PWs are terminated on PE1. If PE1 lost its connection to the working OLT, it SHOULD send an LDP notification message on the protection PW with the Request Switchover bit set.
如图2所示，服务配置有工作PW和保护PW，并且两个PW都在PE1上终止。如果PE1失去与工作OLT的连接，则应在保护PW上发送LDP通知消息，并设置请求切换位。
Upon receiving an LDP notification message from its remote PE with the Request Switchover bit set, a protection OLT MUST activate its optical interface to the protection trunk fiber and activate the associated protection PW, so that traffic can be reliably switched to the protection trunk PON link and the protection PW.
在从其远程PE接收到LDP通知消息并设置了请求切换位后，保护OLT必须激活其到保护中继光纤的光接口，并激活相关的保护PW，以便可以将业务可靠地切换到保护中继PON链路和保护PW。
In the case of Figure 3, the PW-RED State TLV as described in Section 7.1 of [RFC7275] can be used by PE1 to notify PE2 of the faults in all the scenarios, and PE2 operates the same as described in Sections 4.1 to 4.3 of this document.
在图3的情况下，[RFC7275]第7.1节所述的PW-RED状态TLV可由PE1用于通知PE2所有情况下的故障，PE2的操作与本文件第4.1至4.3节所述相同。
Similar to ICCP itself, this ICCP application SHOULD only be used in well-managed and highly monitored service provider PON access networks in a single administrative domain, including the implementation of rogue ONU attachment detection and mitigation via device authentication. Thus, many of the security considerations as described in [RFC7275] apply here as well.
与ICCP本身类似，此ICCP应用程序应仅在单个管理域中的管理良好且受到高度监控的服务提供商PON接入网络中使用，包括通过设备认证实现恶意ONU连接检测和缓解。因此，[RFC7275]中描述的许多安全注意事项也适用于此处。
Again, similar to ICCP, activity on the attachment circuits may cause security threats or be exploited to create denial-of-service attacks. In many passive optical networks, the optical paths between OLT and ONUs traverse publicly accessible facilities including public attachments (e.g., telephone poles), which opens up the risk of excessive link bouncing by optical layer impairment. While ICCP for MC-PON interconnects in the MPLS domain and does not traverse the PON network, risks do include introduction of a malicious ONU that could cause, for example, excessive link bouncing. This link bouncing could result in increased ICCP exchanges similar to the malicious CE case described in [RFC7275]. Operators of such networks should take additional care to restrict unauthorized ONUs and to limit the impact of link bouncing at the OLT, as these could result in service impairment.
同样，与ICCP类似，连接电路上的活动可能导致安全威胁或被利用来创建拒绝服务攻击。在许多无源光网络中，OLT和ONU之间的光路穿过公共可访问的设施，包括公共附件（例如电杆），这增加了光层损坏导致链路过度反弹的风险。虽然用于MC-PON的ICCP在MPLS域中互连，并且不穿过PON网络，但风险确实包括引入恶意ONU，这可能导致过度链路反弹。这种链接跳转可能导致ICCP交换增加，类似于[RFC7275]中描述的恶意CE案例。此类网络的运营商应额外注意限制未经授权的ONU，并限制OLT链路反弹的影响，因为这可能导致服务受损。
IANA maintains a top-level registry called "Pseudowire Name Spaces (PWE3)". It has a subregistry called "ICC RG Parameter Types". The following values have been allocated from this subregistry:
IANA维护一个名为“伪线名称空间（PWE3）”的顶级注册表。它有一个称为“ICC RG参数类型”的子区域。已从该子区域分配了以下值：
0x200D PON Connect TLV 0x200E PON Disconnect TLV 0x200F PON Configuration TLV 0x2010 PON State TLV
0x200D PON连接TLV 0x200E PON断开TLV 0x200F PON配置TLV 0x2010 PON状态TLV
[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>.
[RFC6870] Muley, P., Ed. and M. Aissaoui, Ed., "Pseudowire Preferential Forwarding Status Bit", RFC 6870, DOI 10.17487/RFC6870, February 2013, <http://www.rfc-editor.org/info/rfc6870>.
[RFC6870]Muley，P.，Ed.和M.Aissaoui，Ed.，“伪线优先转发状态位”，RFC 6870，DOI 10.17487/RFC6870，2013年2月<http://www.rfc-editor.org/info/rfc6870>.
[RFC7275] Martini, L., Salam, S., Sajassi, A., Bocci, M., Matsushima, S., and T. Nadeau, "Inter-Chassis Communication Protocol for Layer 2 Virtual Private Network (L2VPN) Provider Edge (PE) Redundancy", RFC 7275, DOI 10.17487/RFC7275, June 2014, <http://www.rfc-editor.org/info/rfc7275>.
[RFC7275]Martini，L.，Salam，S.，Sajassi，A.，Bocci，M.，Matsushima，S.，和T.Nadeau，“第2层虚拟专用网络（L2VPN）提供商边缘（PE）冗余的机箱间通信协议”，RFC 7275，DOI 10.17487/RFC72752014年6月<http://www.rfc-editor.org/info/rfc7275>.
[G.8031] International Telecommunications Union, "Ethernet Linear Protection Switching", ITU-T Recommendation G.8031, January 2015.
[G.8031]国际电信联盟，“以太网线性保护交换”，ITU-T建议G.8031，2015年1月。
[G.8261] International Telecommunications Union, "Timing and synchronization aspects in packet networks", ITU-T Recommendation G.8261, August 2013.
[G.8261]国际电信联盟，“分组网络中的定时和同步方面”，ITU-T建议G.8261，2013年8月。
[G.983.1] International Telecommunications Union, "Broadband optical access systems based on Passive Optical Networks (PON)", ITU-T Recommendation G.983.1, January 2005.
[G.983.1]国际电信联盟，“基于无源光网络（PON）的宽带光接入系统”，ITU-T建议G.983.1，2005年1月。
[IEEE-1588] IEEE, "IEEE Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems", IEEE Std 1588-2008, DOI 10.1109/IEEESTD.2008.4579760, July 2008.
[IEEE-1588]IEEE，“网络测量和控制系统精密时钟同步协议的IEEE标准”，IEEE标准1588-2008，DOI 10.1109/IEEESTD.2008.4579760，2008年7月。
[IEEE-1904.1] IEEE, "Standard for Service Interoperability in Ethernet Passive Optical Networks (SIEPON)", IEEE Std 1904.1-2013, DOI 10.1109/IEEESTD.2013.6605490, June 2013.
[IEEE-1904.1]IEEE，“以太网无源光网络（SIEPON）服务互操作性标准”，IEEE标准1904.1-2013，DOI 10.1109/IEEESTD.2013.66054902013年6月。
[remote-phy] CableLabs, "Remote PHY Specification", DCN: CM-SP-R-PHY-I05-160923, September 2016.
[remote phy]CableLabs，“远程phy规范”，DCN:CM-SP-R-phy-I05-160923，2016年9月。
[RFC6456] Li, H., Zheng, R., and A. Farrel, "Multi-Segment Pseudowires in Passive Optical Networks", RFC 6456, DOI 10.17487/RFC6456, November 2011, <http://www.rfc-editor.org/info/rfc6456>.
[RFC6456]Li，H.，Zheng，R.，和A.Farrel，“无源光网络中的多段伪线”，RFC 6456，DOI 10.17487/RFC6456，2011年11月<http://www.rfc-editor.org/info/rfc6456>.
[TR-221] The Broadband Forum, "Technical Specifications for MPLS in Mobile Backhaul Networks", BBF TR-221, October 2011.
[TR-221]宽带论坛，“移动回程网络中MPLS的技术规范”，BBF TR-221，2011年10月。
Acknowledgements
致谢
The authors would like to thank Min Ye, Hongyu Li, Wei Lin, Xifeng Wan, Yannick Legoff, Shrinivas Joshi, Alexey Melnikov, and Stephen Farrell for their valuable discussions and comments.
作者要感谢叶敏、李洪宇、魏琳、万西峰、Yannick Legoff、Shrinivas Joshi、Alexey Melnikov和Stephen Farrell的宝贵讨论和评论。
Contributors
贡献者
The following people made significant contributions to this document:
以下人员对本文件做出了重大贡献：
Chengbin Shen China Telecom 1835 South Pudong Road Shanghai 200122, China Email: shencb@sttri.com.cn
沈承斌中国电信上海浦东南路1835号，邮编：200122电子邮件：shencb@sttri.com.cn
Guangtao Zhou China Unicom No.9 Shouti South Road Beijing 100048, China Email: zhouguangtao@chinaunicom.cn
中国联通广州市首体南路9号中国北京100048电子邮件：zhouguangtao@chinaunicom.cn
Authors' Addresses
作者地址
Yuanlong Jiang (editor) Huawei Bantian, Longgang district Shenzhen 518129 China
姜元龙（编辑）中国深圳市龙岗区华为坂田518129
Email: jiangyuanlong@huawei.com
Email: jiangyuanlong@huawei.com
Yong Luo Huawei Bantian, Longgang district Shenzhen 518129 China
中国深圳市龙岗区永洛华为银行518129
Email: dennis.luoyong@huawei.com
Email: dennis.luoyong@huawei.com
Edwin Mallette (editor) Charter Communications 4145 S. Falkenburg Road Tampa, FL 33578 United States of America
Edwin Mallette（编辑）Charter Communications 4145南法尔肯堡路坦帕，美国佛罗里达州33578
Email: edwin.mallette@gmail.com
Email: edwin.mallette@gmail.com
Yimin Shen Juniper Networks 10 Technology Park Drive Westford, MA 01886 United States of America
美国马萨诸塞州韦斯特福德科技园大道10号伊敏·申·杜松网络公司01886
Email: yshen@juniper.net
Email: yshen@juniper.net
Weiqiang Cheng China Mobile No.32 Xuanwumen West Street Beijing 100053 China
中国移动北京宣武门西街32号威强城100053
Email: chengweiqiang@chinamobile.com
Email: chengweiqiang@chinamobile.com