Internet Engineering Task Force (IETF) A. Morton
Request for Comments: 5938 AT&T Labs
Updates: 5357 M. Chiba
Category: Standards Track Cisco Systems
ISSN: 2070-1721 August 2010
Internet Engineering Task Force (IETF) A. Morton
Request for Comments: 5938 AT&T Labs
Updates: 5357 M. Chiba
Category: Standards Track Cisco Systems
ISSN: 2070-1721 August 2010
Individual Session Control Feature for the Two-Way Active Measurement Protocol (TWAMP)
双向主动测量协议（TWAMP）的单独会话控制功能
Abstract
摘要
The IETF has completed its work on the core specification of TWAMP -- the Two-Way Active Measurement Protocol. This memo describes an OPTIONAL feature for TWAMP, that gives the controlling host the ability to start and stop one or more individual test sessions using Session Identifiers. The base capability of the TWAMP protocol requires all test sessions that were previously requested and accepted to start and stop at the same time.
IETF已经完成了关于TWAMP核心规范的工作——双向主动测量协议。此备忘录描述了TWAMP的可选功能，该功能使控制主机能够使用会话标识符启动和停止一个或多个单独的测试会话。TWAMP协议的基本功能要求之前请求和接受的所有测试会话同时启动和停止。
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/rfc5938.
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/rfc5938.
Copyright Notice
版权公告
Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2010 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。
This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English.
本文件可能包含2008年11月10日之前发布或公开的IETF文件或IETF贡献中的材料。控制某些材料版权的人员可能未授予IETF信托允许在IETF标准流程之外修改此类材料的权利。在未从控制此类材料版权的人员处获得充分许可的情况下，不得在IETF标准流程之外修改本文件，也不得在IETF标准流程之外创建其衍生作品，除了将其格式化以RFC形式发布或将其翻译成英语以外的其他语言。
Table of Contents
目录
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
2. Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . 4
3. TWAMP Control Extensions . . . . . . . . . . . . . . . . . . . 4
3.1. Connection Setup with Individual Session Control . . . . . 5
3.2. Start-N-Sessions Command with Individual Session
Control . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Start-N-Ack Command with Individual Session Control . . . 7
3.4. Stop-N-Sessions Command with Individual Session Control . 9
3.5. Stop-N-Ack Command with Individual Session Control . . . . 10
3.6. SERVWAIT Timeout Operation . . . . . . . . . . . . . . . . 12
3.7. Additional Considerations . . . . . . . . . . . . . . . . 12
4. TWAMP Test with Individual Session Control . . . . . . . . . . 13
4.1. Sender Behavior . . . . . . . . . . . . . . . . . . . . . 13
4.2. Reflector Behavior . . . . . . . . . . . . . . . . . . . . 13
5. Security Considerations . . . . . . . . . . . . . . . . . . . 14
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
6.1. Registry Specification . . . . . . . . . . . . . . . . . . 14
6.2. Registry Management . . . . . . . . . . . . . . . . . . . 14
6.3. Experimental Numbers . . . . . . . . . . . . . . . . . . . 15
6.4. Registry Contents . . . . . . . . . . . . . . . . . . . . 15
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 16
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.1. Normative References . . . . . . . . . . . . . . . . . . . 16
8.2. Informative References . . . . . . . . . . . . . . . . . . 16
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
2. Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . 4
3. TWAMP Control Extensions . . . . . . . . . . . . . . . . . . . 4
3.1. Connection Setup with Individual Session Control . . . . . 5
3.2. Start-N-Sessions Command with Individual Session
Control . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Start-N-Ack Command with Individual Session Control . . . 7
3.4. Stop-N-Sessions Command with Individual Session Control . 9
3.5. Stop-N-Ack Command with Individual Session Control . . . . 10
3.6. SERVWAIT Timeout Operation . . . . . . . . . . . . . . . . 12
3.7. Additional Considerations . . . . . . . . . . . . . . . . 12
4. TWAMP Test with Individual Session Control . . . . . . . . . . 13
4.1. Sender Behavior . . . . . . . . . . . . . . . . . . . . . 13
4.2. Reflector Behavior . . . . . . . . . . . . . . . . . . . . 13
5. Security Considerations . . . . . . . . . . . . . . . . . . . 14
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
6.1. Registry Specification . . . . . . . . . . . . . . . . . . 14
6.2. Registry Management . . . . . . . . . . . . . . . . . . . 14
6.3. Experimental Numbers . . . . . . . . . . . . . . . . . . . 15
6.4. Registry Contents . . . . . . . . . . . . . . . . . . . . 15
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 16
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.1. Normative References . . . . . . . . . . . . . . . . . . . 16
8.2. Informative References . . . . . . . . . . . . . . . . . . 16
The IETF has completed its work on the core specification of TWAMP -- the Two-Way Active Measurement Protocol [RFC5357]. TWAMP is an extension of the One-way Active Measurement Protocol, OWAMP [RFC4656]. The TWAMP specification gathered wide review as it approached completion, and the by-products were several recommendations for new features in TWAMP. There are a growing number of TWAMP implementations at present, and widespread usage is expected. There are even devices that are designed to test implementations for protocol compliance.
IETF已经完成了关于TWAMP核心规范的工作——双向主动测量协议[RFC5357]。TWAMP是单向主动测量协议OWAMP[RFC4656]的扩展。TWAMP规范在接近完成时得到了广泛的审查，副产品是对TWAMP新特性的几项建议。目前有越来越多的TWAMP实现，预计将广泛使用。甚至还有一些设备被设计用来测试协议遵从性的实现。
This memo describes an OPTIONAL feature for TWAMP. [RFC5357] TWAMP (and OWAMP) start all previously requested and accepted test sessions at once. This feature allows the Control-Client to control individual test sessions on the basis of their Session Identifier (SID). This feature permits a short-duration TWAMP test to start (and/or stop) during a longer test. This feature permits a specific diagnostic test to begin if intermediate results indicate that the test is warranted, for example.
本备忘录描述了TWAMP的可选功能。[RFC5357]TWAMP（和OWAMP）立即启动所有先前请求和接受的测试会话。此功能允许控制客户端根据会话标识符（SID）控制各个测试会话。此功能允许在较长测试期间启动（和/或停止）短时TWAMP测试。例如，如果中间结果表明测试得到保证，则此功能允许开始特定的诊断测试。
This feature requires a Modes field bit position assignment and the use of two new TWAMP command numbers (for the augmented Start and Stop commands). This feature also specifies the use of a new Stop-N-ACK Server response, to complete the symmetry of the session-stopping process in the same way as the Start-ACK (Start-N-ACK when used with this feature) response.
此功能需要模式字段位位置分配和使用两个新的TWAMP命令编号（用于增强的启动和停止命令）。此功能还指定使用新的Stop-N-ACK服务器响应，以与Start ACK（与此功能一起使用时为Start-N-ACK）响应相同的方式完成会话停止过程的对称性。
The Individual Session Control feature gives the Control-Client new flexibility to manage any number of test sessions once they are established. However, [RFC5357] test sessions are established in serial order and the total establishment time grows with the number of sessions and the round-trip time. Therefore, implementers of this feature may also wish to implement the "Reflect Octets" feature, described in [REFLECT]. This feature allows a Control-Client to distinguish between parallel Request-TW-Session commands because a participating Server can return octets (e.g., the Control-Client's local index) in its reply to the request. Thus, the Reflect Octets feature supports the efficient establishment of many simultaneous test sessions that the Individual Session Control feature can then manage (start/stop).
单个会话控制功能为控制客户端提供了新的灵活性，可以在建立测试会话后管理任意数量的测试会话。但是，[RFC5357]测试会话是按串行顺序建立的，总建立时间随着会话数量和往返时间的增加而增加。因此，此功能的实现者可能还希望实现[Reflect]中描述的“Reflect Octets”功能。此功能允许控制客户端区分并行请求TW会话命令，因为参与服务器可以在响应请求时返回八位字节（例如，控制客户端的本地索引）。因此，Reflect Octets功能支持高效地建立许多同时的测试会话，单个会话控制功能随后可以管理这些会话（启动/停止）。
This memo is an update to the TWAMP core protocol specified in [RFC5357]. Measurement systems are not required to implement the feature described in this memo to claim compliance with [RFC5357].
本备忘录是对[RFC5357]中规定的TWAMP核心协议的更新。测量系统无需实现本备忘录中描述的功能，即可声明符合[RFC5357]。
Throughout this memo, the bits marked MBZ (Must Be Zero) MUST be set to zero by senders and MUST be ignored by receivers. Also, the HMAC (Hashed Message Authentication Code) MUST be calculated as defined in Section 3.2 of [RFC4656].
在本备忘录中，标记为MBZ（必须为零）的位必须由发送方设置为零，接收方必须忽略。此外，必须按照[RFC4656]第3.2节中的定义计算HMAC（哈希消息认证码）。
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 purpose of this memo is to describe an additional OPTIONAL function and feature for TWAMP [RFC5357].
本备忘录旨在描述TWAMP[RFC5357]的附加可选功能和特性。
The scope of the memo is limited to specifications of the following features:
备忘录的范围仅限于以下功能的规格：
1. extension of the modes of operation through assignment of a new value in the Modes field to communicate feature capability and use,
1. 通过在模式字段中分配一个新值来扩展操作模式，以传达功能能力和使用，
2. the definitions of augmented start session and stop session commands (with corresponding acknowledgements), and
2. 扩充的启动会话和停止会话命令（带有相应的确认）的定义，以及
3. the definition of related procedures for TWAMP entities.
3. TWAMP实体相关程序的定义。
The motivation for this feature is the ability to start and stop individual test sessions at will, using a single TWAMP-Control connection.
此功能的动机是能够使用单个TWAMP控制连接随意启动和停止单个测试会话。
When the Server and Control-Client have agreed to use the Individual Session Control mode during control connection setup, then the Control-Client, the Server, the Session-Sender, and the Session-Reflector MUST all conform to the requirements of that mode, as identified below. The original TWAMP-Control Start and Stop commands MUST NOT be used.
当服务器和控制客户端同意在控制连接设置期间使用单独的会话控制模式时，控制客户端、服务器、会话发送器和会话反射器都必须符合该模式的要求，如下所示。不得使用原始TWAMP控制启动和停止命令。
The TWAMP-Control protocol is a derivative of the OWAMP-Control protocol, and provides two-way measurement capability. TWAMP [RFC5357] uses the Modes field to identify and select specific communication capabilities, and this field is a recognized extension mechanism. The following sections describe one such extension.
TWAMP控制协议是OWAMP控制协议的衍生产品，提供双向测量能力。TWAMP[RFC5357]使用模式字段来识别和选择特定的通信能力，该字段是公认的扩展机制。以下各节描述了一个这样的扩展。
TWAMP-Control connection establishment follows the procedure defined in Section 3.1 of [RFC4656] OWAMP. The Individual Session Control mode requires one new bit position (and value) to identify the ability of the Server/Session-Reflector to start and stop specific sessions (according to their Session Identifier, or SID). This new feature requires an additional TWAMP mode bit assignment as follows:
TWAMP控制连接的建立遵循[RFC4656]OWAMP第3.1节中定义的程序。单独会话控制模式需要一个新的位位置（和值）来标识服务器/会话反射器启动和停止特定会话的能力（根据会话标识符或SID）。此新功能需要额外的TWAMP模式位分配，如下所示：
Value Description Reference/Explanation
0 Reserved
1 Unauthenticated RFC 4656, Section 3.1
2 Authenticated RFC 4656, Section 3.1
4 Encrypted RFC 4656, Section 3.1
8 Unauth. TEST protocol, RFC 5618, Section 3.1
Encrypted CONTROL
--------------------------------------------------------
16 Individual Session RFC 5938, bit position 4
Control
Value Description Reference/Explanation
0 Reserved
1 Unauthenticated RFC 4656, Section 3.1
2 Authenticated RFC 4656, Section 3.1
4 Encrypted RFC 4656, Section 3.1
8 Unauth. TEST protocol, RFC 5618, Section 3.1
Encrypted CONTROL
--------------------------------------------------------
16 Individual Session RFC 5938, bit position 4
Control
In the original OWAMP Modes field, setting bit positions 0, 1, or 2 indicated the security mode of the Control protocol, and the Test protocol inherited the same mode (see Section 4 of [RFC4656]). In the [RFC5618] memo, bit position (3) allows a different security mode in the Test protocol and uses the unauthenticated test packet format.
在原始OWAMP模式字段中，设置位位置0、1或2表示控制协议的安全模式，测试协议继承了相同的模式（参见[RFC4656]第4节）。在[RFC5618]备忘录中，位位置（3）允许在测试协议中使用不同的安全模式，并使用未经验证的测试数据包格式。
If the Server sets the new bit position (bit position 4) in the Server Greeting message to indicate its capabilities, then the Server and Session-Reflector MUST comply with the requirements of this memo to control sessions on an individual basis if desired.
如果服务器在服务器问候语消息中设置新的位位置（位位置4）以指示其功能，则服务器和会话反射器必须符合本备忘录的要求，以便在需要时单独控制会话。
If the Control-Client intends to control sessions on an individual basis (according to the requirements in this memo), it MUST set the mode bit (4, corresponding to the new mode) in the Setup Response message. This means that:
如果控制客户端打算单独控制会话（根据本备忘录中的要求），则必须在设置响应消息中设置模式位（4，对应于新模式）。这意味着：
1. The Control-Client and the Server MUST use the start and stop commands intended for individual session control and the corresponding acknowledgements, as defined in the sections that follow.
1. 控制客户端和服务器必须使用用于单个会话控制的启动和停止命令以及相应的确认，如以下各节中所定义。
2. The Control-Client and the Server MUST NOT use the start and stop commands (2 and 3) and the acknowledgement defined in [RFC5357].
2. 控制客户端和服务器不得使用启动和停止命令（2和3）以及[RFC5357]中定义的确认。
The Control-Client MUST also set one mode bit to indicate the chosen security mode (currently bits 0, 1, 2, or 3), consistent with the modes offered by the Server. The Control-Client MAY also set Modes
控制客户端还必须设置一个模式位，以指示所选的安全模式（当前为位0、1、2或3），与服务器提供的模式一致。控制客户端还可以设置模式
field bit 4 with other features and bit positions (such as the reflect octets feature).
具有其他特征和位位置（如反射八位字节特征）的字段位4。
Having
有
o initiated Individual Session Control mode in the Setup Response,
o 在设置响应中启动单个会话控制模式，
o requested one or more test sessions, and
o 请求一个或多个测试会话，以及
o received affirmative Accept-Session response(s),
o 收到肯定的接受会话响应，
a TWAMP Client MAY start the execution of one or more test sessions by sending a Start-N-Sessions message to the Server (note that "N" indicates that this command is applicable to one or more sessions, and does not change with the number of sessions identified in the command).
TWAMP客户端可以通过向服务器发送start-N-sessions消息来启动一个或多个测试会话的执行（注意，“N”表示此命令适用于一个或多个会话，并且不会随命令中标识的会话数而改变）。
The format of the Start-N-Sessions message is as follows:
Start-N-Sessions消息的格式如下：
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 7 | |
+-+-+-+-+-+-+-+-+ +
| MBZ (11 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 7 | |
+-+-+-+-+-+-+-+-+ +
| MBZ (11 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
Note: In figures, "B" indicates the boundary of a 16-octet word.
注：在图中，“B”表示16个八位组字的边界。
The Command Number value of 7 indicates that this is a Start-N-Sessions command. The Control-Client MUST compose this command, and the Server MUST interpret this command, according to the field descriptions below.
命令编号值7表示这是一个Start-N-Sessions命令。根据下面的字段描述，控制客户端必须编写此命令，服务器必须解释此命令。
The Number of Sessions field indicates the count of sessions that this Start command applies to, and MUST be one or greater. The number of SID fields that follow MUST be equal to the value in the Number of Sessions field (otherwise, the command MUST NOT be affirmed with a zero Accept field in the Start-N-Ack response).
“会话数”字段指示此Start命令应用于的会话数，必须为一个或多个。后面的SID字段数必须等于会话数字段中的值（否则，在Start-N-Ack响应中不能使用零接受字段确认该命令）。
All SID fields are constructed as defined in the last paragraph of Section 3.5 of OWAMP [RFC4656] (and referenced in TWAMP). Note that the SID is assigned by the Server during the session request exchange.
所有SID字段均按照OWAMP[RFC4656]第3.5节最后一段的定义构造（并在TWAMP中引用）。请注意，SID是在会话请求交换期间由服务器分配的。
The message is terminated with a single block HMAC, as illustrated above.
消息以单个块HMAC终止，如上所示。
The Server MUST respond with one or more Start-N-Ack messages (which SHOULD be sent as quickly as possible). Start-N-Ack messages SHALL have the format defined in the next session.
服务器必须响应一条或多条Start-N-Ack消息（应尽快发送）。Start-N-Ack消息的格式应在下一个会话中定义。
When using Individual Session Control mode and its Start-N-Ack command as described in the next section, multiple Start-N-Sessions commands MAY be sent without waiting for acknowledgement, and the Start-N-sessions commands MAY arrive in any order.
当使用单个会话控制模式及其Start-N-Ack命令（如下一节所述）时，可以在不等待确认的情况下发送多个Start-N-Sessions命令，并且Start-N-Sessions命令可以以任何顺序到达。
The Server responds to the Start-N-Sessions command (for one or more specific sessions referenced by their SIDs) with one or more Start-N-Ack commands with Accept fields corresponding to one or more of the SIDs. This allows for the possibility that a Server cannot immediately start one or more of the sessions referenced in a particular Start-N-Sessions command, but can start one or more of the sessions.
服务器使用一个或多个Start-N-Ack命令响应Start-N-Sessions命令（对于其SID引用的一个或多个特定会话），该命令带有与一个或多个SID对应的Accept字段。这允许服务器无法立即启动特定start-N-sessions命令中引用的一个或多个会话，但可以启动一个或多个会话。
The format of the message is as follows:
电文格式如下：
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 8 | Accept | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 8 | Accept | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Command Number value of 8 indicates that this is a Start-N-Ack message. The Server MUST compose this command, and the Control-Client MUST interpret this command, according to the field descriptions below.
命令编号值8表示这是一条Start-N-Ack消息。根据下面的字段描述，服务器必须编写此命令，而控制客户端必须解释此命令。
The Accept field values are defined in Section 3.3 of OWAMP [RFC4656].
接受字段值在OWAMP[RFC4656]第3.3节中定义。
The Number of Sessions field indicates the count of sessions that this Start-N-Ack command applies to, and MUST be one or greater. The number of SID fields that follow MUST be equal to the value in the Number of Sessions field.
“会话数”字段指示此Start-N-Ack命令应用于的会话数，必须为一个或多个。后面的SID字段数必须等于会话数字段中的值。
All SID fields are constructed as defined in the last paragraph of Section 3.5 of OWAMP [RFC4656] (and referenced in TWAMP). Note that the SID is assigned by the Server during the session request exchange.
所有SID字段均按照OWAMP[RFC4656]第3.5节最后一段的定义构造（并在TWAMP中引用）。请注意，SID是在会话请求交换期间由服务器分配的。
The message is terminated with a single block HMAC, as illustrated above.
消息以单个块HMAC终止，如上所示。
Note that the SIDs for all Sessions with the same 'Accept' code can be acknowledged using the same Start-N-Ack message.
请注意，可以使用相同的Start-N-Ack消息确认具有相同“接受”代码的所有会话的SID。
For example, say that the Server receives a Start-N-Sessions command for SIDs 1, 2, 3, and 4. The Server determines that the resources for SID=3 are temporarily unavailable. The Server responds with two Start-N-Ack commands with fields as follows:
例如，假设服务器接收到用于SID 1、2、3和4的Start-N-Sessions命令。服务器确定SID=3的资源暂时不可用。服务器响应两个Start-N-Ack命令，字段如下：
Accept = 0 Number of Sessions = 3 SIDs 1, 2, 4
接受=0会话数=3个SID 1、2、4
Accept = 5 Number of Sessions = 1 SID 3
接受=5会话数=1 SID 3
The Stop-N-Sessions command can only be issued by the Control-Client. The command MUST contain at least one SID.
Stop-N-Sessions命令只能由控制客户端发出。该命令必须至少包含一个SID。
The TWAMP Stop-N-Sessions command for use in Individual Session Control mode is formatted as follows:
用于单独会话控制模式的TWAMP Stop-N-Sessions命令的格式如下：
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 9 | |
+-+-+-+-+-+-+-+-+ +
| MBZ (11 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 9 | |
+-+-+-+-+-+-+-+-+ +
| MBZ (11 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
The Command Number value of 9 indicates that this is a Stop-N-Sessions command. The Control-Client MUST compose this command, and the Server MUST interpret this command, according to the field descriptions below.
命令编号值9表示这是一个Stop-N-Sessions命令。根据下面的字段描述，控制客户端必须编写此命令，服务器必须解释此命令。
The Number of Sessions field indicates the count of sessions to which this Stop-N-Sessions command applies. The SID is as defined in Section 3.5 of OWAMP [RFC4656] (and TWAMP), and the value MUST be one or greater. The number of SID fields that follow MUST be equal to the value in the Number of Sessions field.
“会话数”字段指示此Stop-N-Sessions命令应用的会话数。SID如OWAMP[RFC4656]（和TWAMP）第3.5节所定义，且该值必须为一个或更大。后面的SID字段数必须等于会话数字段中的值。
The message is terminated with a single block HMAC, as illustrated above.
消息以单个块HMAC终止，如上所示。
The Server MUST respond with one or more Stop-N-Ack messages (which SHOULD be sent as quickly as possible). Stop-N-Ack messages SHALL have the format defined in the next session.
服务器必须响应一条或多条Stop-N-Ack消息（应尽快发送）。Stop-N-Ack消息的格式应在下一个会话中定义。
In response to the Stop-N-Sessions command (for one or more specific sessions referenced by their SIDs), the Server MUST reply with one or more Stop-N-Ack commands with Accept fields corresponding to one or more of the SIDs. This allows for the possibility that a Server cannot immediately stop one or more of the sessions referenced in a particular Stop-N-Sessions command, but can stop one or more of the sessions.
为了响应Stop-N-Sessions命令（对于其SID引用的一个或多个特定会话），服务器必须使用一个或多个Stop-N-Ack命令以及对应于一个或多个SID的Accept字段进行回复。这使得服务器可能无法立即停止特定stop-N-sessions命令中引用的一个或多个会话，但可以停止一个或多个会话。
The format for the Stop-N-Ack command is as follows:
Stop-N-Ack命令的格式如下：
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 10 | Accept | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| 10 | Accept | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number of Sessions |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| First SID (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
. remaining SIDs (16 octets each) .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+B
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Command Number value of 10 indicates that this is a Stop-N-Ack message. The Server MUST compose this command, and the Control-Client MUST interpret this command, according to the field descriptions below.
命令编号值10表示这是一条Stop-N-Ack消息。根据下面的字段描述，服务器必须编写此命令，而控制客户端必须解释此命令。
The Accept Field values are defined in Section 3.3 of OWAMP [RFC4656].
接受字段值在OWAMP[RFC4656]第3.3节中定义。
The Number of Sessions field indicates the count of sessions that this Stop-N-Ack command applies to, and MUST be one or greater. The number of SID fields that follow MUST be equal to the value in the Number of Sessions field.
“会话数”字段指示此Stop-N-Ack命令应用于的会话数，必须为一个或多个。后面的SID字段数必须等于会话数字段中的值。
All SID fields are constructed as defined in the last paragraph of Section 3.5 of OWAMP [RFC4656] (and referenced in TWAMP). Note that the SID is assigned by the Server during the session request exchange.
所有SID字段均按照OWAMP[RFC4656]第3.5节最后一段的定义构造（并在TWAMP中引用）。请注意，SID是在会话请求交换期间由服务器分配的。
The message is terminated with a single block HMAC, as illustrated above.
消息以单个块HMAC终止，如上所示。
Note that the SIDs for all Sessions with the same 'Accept' code can be acknowledged using the same Stop-N-Ack message.
请注意，可以使用相同的Stop-N-Ack消息确认具有相同“接受”代码的所有会话的SID。
Section 3.1 of [RFC5357] describes the operation of the optional SERVWAIT timer. In normal TWAMP operation, the Server suspends monitoring the SERVWAIT timer while test sessions are in progress. When the Individual Session Control feature is utilized, this suspension is extended to cover the time when ANY test session is in progress.
[RFC5357]第3.1节描述了可选SERVWAIT定时器的操作。在正常的TWAMP操作中，当测试会话正在进行时，服务器暂停监视SERVWAIT计时器。当使用单独会话控制功能时，此暂停会延长，以覆盖任何测试会话正在进行的时间。
Thus, the Server SHALL suspend monitoring control connection activity after receiving any Start-N-Sessions command, and after receiving a Stop-N-Sessions command for all corresponding SIDs (and no test sessions are in progress), OR when REFWAIT expires on ALL test sessions initiated by a TWAMP-Control connection, then the SERVWAIT monitoring SHALL resume (as though a Stop-N-Sessions command had been received). An implementation that supports the SERVWAIT timeout option SHOULD also implement the REFWAIT timeout option.
因此，服务器应在收到任何Start-N-Sessions命令后，以及在收到所有对应SID的Stop-N-Sessions命令（且无测试会话正在进行）后，或在TWAMP控制连接启动的所有测试会话上REFWAIT过期时，暂停监控连接活动，然后，SERVWAIT监控应恢复（如同已接收到Stop-N-Sessions命令）。支持SERVWAIT超时选项的实现还应实现REFWAIT超时选项。
The diagram below illustrates the operation of timers SERVWAIT and REFWAIT.
下图说明了计时器SERVWAIT和REFWAIT的操作。
SERVWAIT REFWAIT SERVWAIT
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+
(no sessions
in progress)
+-+-+-+-+-+-+-+-+-+-+-+
SID="1"
SERVWAIT REFWAIT SERVWAIT
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+
(no sessions
in progress)
+-+-+-+-+-+-+-+-+-+-+-+
SID="1"
+-+-+-+-+
SID="2"
+-+-+-+-+
SID="2"
+-+-+-+-+-+-+-+-+
SID="3"
+-+-+-+-+-+-+-+-+
SID="3"
>>>>>>>>>> Time >>>>>>>>>>>>>>>>>>> Time >>>>>>>>>>>>>>>> Time >>>>>
>>>>>>>>>> Time >>>>>>>>>>>>>>>>>>> Time >>>>>>>>>>>>>>>> Time >>>>>
The value of the Modes field sent by the Server (in the Server Greeting message) is the bit-wise OR of the mode values that it is willing to support during this session.
服务器发送的模式字段（在服务器问候语消息中）的值是按位或在此会话期间它愿意支持的模式值。
With the publication of this feature, bit positions 0 through 4 of the 32-bit Modes field are used. A Control-Client MAY ignore bit positions greater than 2 in the Modes field, or it MAY support
发布此功能后，将使用32位模式字段中的位位置0到4。控制客户端可以忽略模式字段中大于2的位位置，也可以支持
OPTIONAL features that are communicated in bit positions 3 and higher. (The unassigned bits are available for future protocol extensions.)
在位位置3和更高位置通信的可选特性。（未分配的位可用于将来的协议扩展。）
Other ways in which TWAMP extends OWAMP are described in [RFC5357].
[RFC5357]中描述了TWAMP扩展OWAMP的其他方式。
The TWAMP test protocol is similar to the OWAMP [RFC4656] test protocol with the exception that the Session-Reflector transmits test packets to the Session-Sender in response to each test packet it receives. TWAMP [RFC5357] defines two different test packet formats, one for packets transmitted by the Session-Sender and one for packets transmitted by the Session-Reflector. As with the OWAMP-Test protocol, there are three security modes: unauthenticated, authenticated, and encrypted. The unauthenticated mode has one test packet format, while the authenticated and encrypted modes use another (common) format.
TWAMP测试协议类似于OWAMP[RFC4656]测试协议，不同之处在于会话反射器将测试数据包发送给会话发送器，以响应其接收到的每个测试数据包。TWAMP[RFC5357]定义了两种不同的测试数据包格式，一种用于会话发送器发送的数据包，另一种用于会话反射器发送的数据包。与OWAMP测试协议一样，有三种安全模式：未经验证、已验证和已加密。未经验证的模式有一种测试数据包格式，而经过验证和加密的模式使用另一种（通用）格式。
The individual session control feature requires that the sender MUST manage test sessions according to their SID. Otherwise, the sender behavior is as described in Section 4.1 of [RFC5357].
单个会话控制功能要求发送方必须根据其SID管理测试会话。否则，发送方行为如[RFC5357]第4.1节所述。
The TWAMP Reflector follows the procedures and guidelines in Section 4.2 of [RFC5357], with the following additional functions required by this feature:
TWAMP反射器遵循[RFC5357]第4.2节中的程序和指南，并具有此功能所需的以下附加功能：
o The Session-Reflector MUST manage all test sessions accepted according to their SID.
o 会话反射器必须根据其SID管理所有接受的测试会话。
o Upon receipt of a TWAMP-Control Stop-N-Sessions command referencing a specific session/SID, the Session-Reflector MUST ignore TWAMP-Test packets (in the same session/SID) that arrive at the current time plus the Timeout (in the Request-TW-Session command and assuming subsequent acknowledgement). The Session-Reflector MUST NOT generate a test packet to the Session-Sender for packets that are ignored. (Note: The Request-TW-Session command includes sender address + port and receiver address + port, and this is usually sufficient to distinguish sessions.)
o 在收到引用特定会话/SID的TWAMP Control Stop-N-Sessions命令后，会话反射器必须忽略到达当前时间加上超时的TWAMP测试数据包（在请求TW会话命令中，并假设后续确认）。会话反射器不得为被忽略的数据包向会话发送器生成测试数据包。（注意：Request TW Session命令包括发送方地址+端口和接收方地址+端口，这通常足以区分会话。）
o If the REFWAIT timer is implemented, it SHOULD be enforced when any test session is in progress (started and not stopped).
o 如果实现了REFWAIT计时器，则应在任何测试会话正在进行时（启动和未停止）强制执行该计时器。
The security considerations that apply to any active measurement of live networks are relevant here as well. See the security considerations in [RFC4656] and [RFC5357].
适用于实时网络的任何主动测量的安全注意事项也与此相关。请参阅[RFC4656]和[RFC5357]中的安全注意事项。
As a result of this document, IANA has assigned one mode bit position/value for a mode in the IANA registry for the TWAMP Modes field, and this memo describes the behavior when the new mode is used. This field is a recognized extension mechanism for TWAMP.
作为本文档的结果，IANA在IANA注册表中为TWAMP Modes字段的模式分配了一个模式位位置/值，本备忘录描述了使用新模式时的行为。此字段是公认的TWAMP扩展机制。
As a result of this document, IANA has assigned four command numbers in the "TWAMP-Control Command Numbers" registry, and this memo describes the use of the new commands. The command number field is a recognized extension mechanism for TWAMP.
作为本文件的结果，IANA在“TWAMP控制命令编号”注册表中分配了四个命令编号，本备忘录描述了新命令的使用。命令编号字段是公认的TWAMP扩展机制。
IANA has created a "TWAMP-Modes" registry (as requested in [RFC5618]). TWAMP-Modes are specified in TWAMP Server Greeting messages and Set-Up-Response messages, as described in Section 3.1 of [RFC5357], consistent with Section 3.1 of [RFC4656], and extended by this memo. Modes are indicated by setting bits in the 32-bit Modes field that correspond to values in the "TWAMP-Modes" registry. For the "TWAMP-Modes" registry, we expect that new features will be assigned increasing registry values that correspond to single bit positions, unless there is a good reason to do otherwise (more complex encoding than single bit positions may be used in the future to access the 2^32 value space).
IANA已经创建了一个“TWAMP模式”注册表（如[RFC5618]中所要求）。TWAMP模式在TWAMP服务器问候信息和设置响应信息中指定，如[RFC5357]第3.1节所述，与[RFC4656]第3.1节一致，并由本备忘录扩展。通过在32位模式字段中设置与“TWAMP模式”注册表中的值相对应的位来指示模式。对于“TWAMP模式”注册表，我们预计新功能将被分配到与单位位置相对应的越来越多的注册表值，除非有充分的理由这样做（将来可能会使用比单位位置更复杂的编码来访问2^32值空间）。
IANA has also created the "TWAMP-Control Command Numbers" registry. TWAMP-Control commands are specified by the first octet in TWAMP-Control messages as specified in Section 3.5 of [RFC5357], and augmented by this memo. This registry may contain 256 possible values.
IANA还创建了“TWAMP控制命令编号”注册表。TWAMP控制命令由[RFC5357]第3.5节规定的TWAMP控制消息中的第一个八位字节指定，并由本备忘录进行补充。此注册表可能包含256个可能的值。
Because the "TWAMP-Control Command Numbers" registry can contain only 256 values and "TWAMP-Modes" are based on only 32 bit positions with a maximum of 2^32 values, and because TWAMP is an IETF protocol, these registries must be updated only by "IETF Consensus" as specified in [RFC5226] (an RFC that documents registry use and is approved by the IESG). Management of these registries is described in Section 8.2 of [RFC5357] and [RFC5618].
由于“TWAMP控制命令编号”注册表只能包含256个值，“TWAMP模式”仅基于32位位置，最大值为2^32，并且由于TWAMP是一个IETF协议，因此这些注册表只能通过[RFC5226]中规定的“IETF共识”进行更新（记录注册表使用并经IESG批准的RFC）。这些注册表的管理在[RFC5357]和[RFC5618]的第8.2节中进行了说明。
The values 7, 8, 9, and 10 have been assigned in the "TWAMP-Control Command Numbers" Registry. The value 16 corresponding to the next available bit position (4) (as described in Sections 3.1 and 3.7) has been assigned in the "TWAMP-Modes" registry.
值7、8、9和10已在“TWAMP控制命令编号”注册表中分配。对应于下一个可用位位置（4）（如第3.1节和第3.7节所述）的值16已在“TWAMP模式”注册表中分配。
One experimental value has been assigned in the "TWAMP-Control Command Numbers" registry.
在“TWAMP控制命令编号”注册表中分配了一个实验值。
No additional experimental values are assigned in the TWAMP-Modes registry.
TWAMP模式注册表中未指定其他实验值。
TWAMP-Control Command Numbers Registry
TWAMP控制命令编号注册表
Value Description Semantics Definition
0 Reserved
1 Forbidden
2 Start-Sessions RFC 4656, Section 3.7
3 Stop-Sessions RFC 4656, Section 3.8
4 Reserved
5 Request-TW-Session RFC 5357, Section 3.5
6 Experimentation RFC 5357, Section 8.3
------------------------------------------------------------------
7 Start-N-Sessions RFC 5938, Section 3.2
8 Start-N-Ack RFC 5938, Section 3.3
9 Stop-N-Sessions RFC 5938, Section 3.4
10 Stop-N-Ack RFC 5938, Section 3.5
Value Description Semantics Definition
0 Reserved
1 Forbidden
2 Start-Sessions RFC 4656, Section 3.7
3 Stop-Sessions RFC 4656, Section 3.8
4 Reserved
5 Request-TW-Session RFC 5357, Section 3.5
6 Experimentation RFC 5357, Section 8.3
------------------------------------------------------------------
7 Start-N-Sessions RFC 5938, Section 3.2
8 Start-N-Ack RFC 5938, Section 3.3
9 Stop-N-Sessions RFC 5938, Section 3.4
10 Stop-N-Ack RFC 5938, Section 3.5
TWAMP-Modes Registry
TWAMP模式注册表
Value Description Reference/Explanation
0 Reserved
1 Unauthenticated RFC 4656, Section 3.1
2 Authenticated RFC 4656, Section 3.1
4 Encrypted RFC 4656, Section 3.1
8 Unauth. TEST protocol, RFC 5618, Section 3.1
Encrypted CONTROL
--------------------------------------------------------
16 Individual Session RFC 5938, Section 3.1
Control bit position 4
Value Description Reference/Explanation
0 Reserved
1 Unauthenticated RFC 4656, Section 3.1
2 Authenticated RFC 4656, Section 3.1
4 Encrypted RFC 4656, Section 3.1
8 Unauth. TEST protocol, RFC 5618, Section 3.1
Encrypted CONTROL
--------------------------------------------------------
16 Individual Session RFC 5938, Section 3.1
Control bit position 4
The authors thank everyone who provided comments on this feature, especially Lars Eggert, Adrian Farrel, and Alexey Melnikov.
作者感谢所有对此功能提供评论的人，特别是Lars Eggert、Adrian Farrel和Alexey Melnikov。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M. Zekauskas, "A One-way Active Measurement Protocol (OWAMP)", RFC 4656, September 2006.
[RFC4656]Shalunov，S.，Teitelbaum，B.，Karp，A.，Boote，J.，和M.Zekauskas，“单向主动测量协议（OWAMP）”，RFC 46562006年9月。
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.
[RFC5226]Narten，T.和H.Alvestrand，“在RFCs中编写IANA注意事项部分的指南”，BCP 26，RFC 5226，2008年5月。
[RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J. Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)", RFC 5357, October 2008.
[RFC5357]Hedayat，K.，Krzanowski，R.，Morton，A.，Yum，K.，和J.Babiarz，“双向主动测量协议（TWAMP）”，RFC 5357，2008年10月。
[RFC5618] Morton, A. and K. Hedayat, "Mixed Security Mode for the Two-Way Active Measurement Protocol (TWAMP)", RFC 5618, August 2009.
[RFC5618]Morton，A.和K.Hedayat，“双向主动测量协议（TWAMP）的混合安全模式”，RFC 5618，2009年8月。
[REFLECT] Morton, A. and L. Ciavattone, "TWAMP Reflect Octets and Symmetrical Size Features", Work in Progress, June 2010.
[反映]Morton，A.和L.Ciavattone，“TWAMP反映八位组和对称大小特征”，正在进行的工作，2010年6月。
Authors' Addresses
作者地址
Al Morton AT&T Labs 200 Laurel Avenue South Middletown, NJ 07748 USA
美国新泽西州劳雷尔大道南米德尔顿200号阿尔莫顿AT&T实验室，邮编：07748
Phone: +1 732 420 1571
Fax: +1 732 368 1192
EMail: acmorton@att.com
URI: http://home.comcast.net/~acmacm/
Phone: +1 732 420 1571
Fax: +1 732 368 1192
EMail: acmorton@att.com
URI: http://home.comcast.net/~acmacm/
Murtaza Chiba Cisco Systems 170 W. Tasman Drive San Jose, CA 95134 USA
美国加利福尼亚州圣何塞塔斯曼大道西170号Murtaza Chiba Cisco Systems，邮编95134
Phone: +1 800 553 NETS
EMail: mchiba@cisco.com
Phone: +1 800 553 NETS
EMail: mchiba@cisco.com