Network Working Group L. Coene
Request for Comments: 4166 Siemens
Category: Informational J. Pastor-Balbas
Ericsson
February 2006
Network Working Group L. Coene
Request for Comments: 4166 Siemens
Category: Informational J. Pastor-Balbas
Ericsson
February 2006
Telephony Signalling Transport over Stream Control Transmission Protocol (SCTP) Applicability Statement
流控制传输协议（SCTP）上的电话信令传输适用性声明
Status of This Memo
关于下段备忘
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
本备忘录为互联网社区提供信息。它没有规定任何类型的互联网标准。本备忘录的分发不受限制。
Copyright Notice
版权公告
Copyright (C) The Internet Society (2006).
版权所有（C）互联网协会（2006年）。
Abstract
摘要
This document describes the applicability of the several protocols developed under the signalling transport framework. A description of the main issues regarding the use of the Stream Control Transmission Protocol (SCTP) and an explanation of each adaptation layer for transport of telephony signalling information over IP infrastructure are given.
本文件描述了在信令传输框架下开发的几种协议的适用性。本文描述了与使用流控制传输协议（SCTP）有关的主要问题，并解释了通过IP基础设施传输电话信令信息的每个适配层。
Table of Contents
目录
1. Introduction ....................................................2
1.1. Scope ......................................................2
1.2. Terminology ................................................3
1.3. Contributors ...............................................3
2. SIGTRAN Architecture ............................................3
3. Issues for Transporting Telephony Signalling over SCTP ..........5
3.1. Congestion Control .........................................5
3.2. Detection of Failures ......................................6
3.2.1. Retransmission TimeOut (RTO) Calculation ............6
3.2.2. Heartbeat ...........................................7
3.2.3. Maximum Number of Retransmissions ...................7
3.3. Shorten End-to-End Message Delay ...........................7
3.4. Bundling Considerations ....................................7
3.5. Stream Usage ...............................................7
4. User Adaptation Layers ..........................................7
4.1. Access Signalling .........................................10
4.1.1. IUA (ISDN Q.921 User Adaptation) ...................10
4.1.2. V5UA (V5.2-User Adaptation) Layer ..................12
4.1.3. DUA (DPNSS/DASS User adaptation) Layer .............13
4.2. Network Signalling ........................................13
4.2.1. MTP lvl3 over IP ...................................14
4.2.2. M3UA (SS7 MTP3 User Adaptation) Layer ..............17
4.2.3. SUA (SS7 SCCP User Adaptation) Layer ...............18
5. Security Considerations ........................................20
6. Informative References .........................................20
1. Introduction ....................................................2
1.1. Scope ......................................................2
1.2. Terminology ................................................3
1.3. Contributors ...............................................3
2. SIGTRAN Architecture ............................................3
3. Issues for Transporting Telephony Signalling over SCTP ..........5
3.1. Congestion Control .........................................5
3.2. Detection of Failures ......................................6
3.2.1. Retransmission TimeOut (RTO) Calculation ............6
3.2.2. Heartbeat ...........................................7
3.2.3. Maximum Number of Retransmissions ...................7
3.3. Shorten End-to-End Message Delay ...........................7
3.4. Bundling Considerations ....................................7
3.5. Stream Usage ...............................................7
4. User Adaptation Layers ..........................................7
4.1. Access Signalling .........................................10
4.1.1. IUA (ISDN Q.921 User Adaptation) ...................10
4.1.2. V5UA (V5.2-User Adaptation) Layer ..................12
4.1.3. DUA (DPNSS/DASS User adaptation) Layer .............13
4.2. Network Signalling ........................................13
4.2.1. MTP lvl3 over IP ...................................14
4.2.2. M3UA (SS7 MTP3 User Adaptation) Layer ..............17
4.2.3. SUA (SS7 SCCP User Adaptation) Layer ...............18
5. Security Considerations ........................................20
6. Informative References .........................................20
This document is intended to describe how to transport telephony signalling protocols, used in classic telephony systems, over IP networks. As described in [RFC2719], the whole architecture is called SIGTRAN (Signalling Transport) and is composed of a transport protocol (SCTP) and several User Adaptation Layers (UALs). The transport protocol SCTP has been developed to fulfill the stringent requirements of telephony signalling networks [RFC3257]. The set of UALs has also been introduced to make it possible for different signalling protocols to use the SCTP layer.
本文档旨在描述如何通过IP网络传输经典电话系统中使用的电话信令协议。如[RFC2719]所述，整个体系结构称为SIGTRAN（信令传输），由传输协议（SCTP）和多个用户适配层（ALS）组成。传输协议SCTP的开发是为了满足电话信令网络[RFC3257]的严格要求。还引入了一组ALS，以使不同的信令协议能够使用SCTP层。
The scope of this document is the SIGTRAN user adaptation layers and SCTP protocols and how they are used to transport telephony signalling information over IP networks.
本文档的范围是SIGTRAN用户适配层和SCTP协议，以及如何使用它们通过IP网络传输电话信令信息。
The following terms are commonly identified in related work:
以下术语通常在相关工作中确定：
Association: SCTP connection between two endpoints.
关联：两个端点之间的SCTP连接。
Stream: A uni-directional logical channel established within an association, within which all user messages are delivered in sequence except for those submitted to the unordered delivery service.
流：在关联中建立的单向逻辑通道，在该通道中，除提交给无序传递服务的消息外，所有用户消息都按顺序传递。
SPU: Signalling protocol user, the application on top of the User adaptation layer.
SPU：信令协议用户，位于用户适配层之上的应用程序。
CTSP: Classical Telephony Signalling Protocol (examples include: MTP level 2, MTP level 3, and SCCP).
CTSP：经典的电话信令协议（示例包括：MTP级别2、MTP级别3和SCCP）。
UAL: User Adaptation Layer, the protocol that encapsulates the upper layer telephony signalling protocols that are to be transported over SCTP/IP.
UAL：用户适配层，封装将通过SCTP/IP传输的上层电话信令协议的协议。
ISEP: IP Signalling Endpoint, an IP node that implements SCTP and a User adaptation layer.
ISEP：IP信令端点，实现SCTP和用户适配层的IP节点。
SP: Signalling Point.
SP：信号点。
The following people contributed to the document: L. Coene (Editor), M. Tuexen, G. Verwimp, J. Loughney, R.R. Stewart, Qiaobing Xie, M. Holdrege, M.C. Belinchon, A. Jungmaier, J. Pastor, and L. Ong.
以下人士对该文件作出了贡献：L.Coene（编辑）、M.Tuexen、G.Verwimp、J.Loughney、R.R.Stewart、谢乔冰、M.Holdrege、M.C.Belinchon、A.Jungmaier、J.Pastor和L.Ong。
The SIGTRAN architecture describes the transport of signalling information over IP infrastructure.
SIGTRAN体系结构描述了通过IP基础设施传输信令信息。
Telephony signalling transport over IP normally uses the following architecture:
IP上的电话信令传输通常使用以下体系结构：
Telephony Signalling Protocol
|
+------------------------------------+
| User Adaptation Layers |
+------------------------------------+
|
+------------------------------------+
|Stream Control Transmission Protocol|
| (SCTP) |
+------------------------------------+
|
Internet Protocol (IPv4/IPv6)
Telephony Signalling Protocol
|
+------------------------------------+
| User Adaptation Layers |
+------------------------------------+
|
+------------------------------------+
|Stream Control Transmission Protocol|
| (SCTP) |
+------------------------------------+
|
Internet Protocol (IPv4/IPv6)
Figure 1: Telephony SIGnalling TRANsport Protocol Stack
图1：电话信令传输协议栈
The components of the protocol stack are:
协议栈的组件包括：
1. Adaptation layers used when the telephony application needs to preserve an existing primitive interface (e.g., management indications or data operation primitives for a particular user/application protocol). 2. SCTP, specially configured to meet the telephony application performance requirements. 3. The standard Internet Protocol.
1. 当电话应用程序需要保留现有原语接口（例如，特定用户/应用程序协议的管理指示或数据操作原语）时使用的适配层。2.SCTP，专门配置为满足电话应用程序性能要求。3.标准互联网协议。
The telephony signalling protocols to be transported can be:
要传输的电话信令协议可以是：
o [RFC3332] SS7 MTP3 users: SCCP, ISUP, TUP...
o [RFC3331] SS7 MTP2 users: MTP3
o [RFC3868] SS7 SCCP users: RANAP, MAP(+TCAP), INAP(+TCAP)...
o [RFC3057] ISDN Q.921 users: Q.931
o [RFC3807] V5.2 / DSS1
o ....
o [RFC3332] SS7 MTP3 users: SCCP, ISUP, TUP...
o [RFC3331] SS7 MTP2 users: MTP3
o [RFC3868] SS7 SCCP users: RANAP, MAP(+TCAP), INAP(+TCAP)...
o [RFC3057] ISDN Q.921 users: Q.931
o [RFC3807] V5.2 / DSS1
o ....
The user adaptation layers (UALs) are a set of protocols that encapsulate a specific signalling protocol to be transported over SCTP. The adaption is done in a way that the upper signalling protocols, which are relayed, remain unaware that the lower layers are different from the original lower telephony signalling layers. In that sense, the upper interface of the user adaptation layers needs to be the same as the upper layer interface is to its original lower layer. If a MTP user is being relayed over the IP network, the related UAL used to transport the MTP user will have the same upper interface as MTP has.
用户适配层（ALS）是一组协议，封装了要通过SCTP传输的特定信令协议。自适应是以这样一种方式完成的，即中继的上层信令协议不知道下层与原始的下层电话信令层不同。从这个意义上讲，用户适配层的上层接口需要与上层接口与其原始下层接口相同。如果通过IP网络中继MTP用户，则用于传输MTP用户的相关UAL将具有与MTP相同的上层接口。
The Stream Control Transmission Protocol was designed to fulfill the stringent transport requirements that classical signalling protocols have and is therefore the recommended transport protocol to use for this purpose.
流控制传输协议旨在满足经典信令协议所具有的严格传输要求，因此是推荐用于此目的的传输协议。
SCTP provides the following functions:
SCTP提供以下功能：
o Reliable Data Transfer o Multiple streams to help avoid head-of-line blocking o Ordered and unordered data delivery on a per-stream basis o Bundling and fragmentation of user data o Congestion and flow control o Support for continuous monitoring of reachability o Graceful termination of association o Support of multi-homing for added reliability o Protection against blind denial-of-service attacks o Protection against blind masquerade attacks
o 可靠的数据传输o多个数据流以帮助避免线首阻塞o基于每个数据流的有序和无序数据交付o捆绑和分割用户数据o拥塞和流量控制o支持连续监控可达性o优雅终止关联o支持多归属以提高可靠性o针对盲目拒绝服务攻击的保护o针对盲目伪装攻击的保护
SCTP is used as the transport protocol for telephony signalling applications. Message boundaries are preserved during data transport by SCTP, so each UAL can specify its own message structure within the SCTP user data. The SCTP user data can be delivered by the order of transmission within a stream (in sequence delivery) or unordered.
SCTP用作电话信令应用的传输协议。SCTP在数据传输期间保留消息边界，因此每个UAL可以在SCTP用户数据中指定自己的消息结构。SCTP用户数据可以按流内的传输顺序（按顺序传输）或无序传输。
SCTP can be used to provide redundancy at the transport layer and below. Telephony applications needing this level of redundancy can make use of SCTP's multi-homing support.
SCTP可用于在传输层及以下提供冗余。需要这种冗余级别的电话应用程序可以利用SCTP的多主支持。
SCTP can be used for telephony applications where head-of-line blocking is a concern. Such an application should use multiple streams to provide independent ordering of telephony signalling messages.
SCTP可用于需要考虑线路阻塞的电话应用。这样的应用程序应该使用多个流来提供电话信令消息的独立排序。
Transport of telephony signalling requires special considerations. In order to use SCTP, an implementation must take special care to meet the performance, timing, and failure management requirements.
电话信号传输需要特别考虑。为了使用SCTP，实现必须特别注意满足性能、时间和故障管理要求。
The basic mechanism of congestion control in SCTP has been described in [RFC2960]. SCTP congestion control sometimes conflicts with the timing requirements of telephony signalling application messages which are transported by SCTP. During congestion, messages may be delayed by SCTP, thus sometimes violating the timing requirements of those telephony applications.
[RFC2960]中描述了SCTP中拥塞控制的基本机制。SCTP拥塞控制有时与SCTP传输的电话信令应用消息的定时要求冲突。在拥塞期间，SCTP可能会延迟消息，因此有时会违反这些电话应用程序的定时要求。
In an engineered network (e.g., a private intranet), in which network capacity and maximum traffic are very well controlled, some telephony signalling applications may choose to relax the congestion control rules of SCTP in order to satisfy the timing requirements. In order to do this, they should employ their own congestion control mechanisms. This must be done without destabilizing the network; otherwise, it would lead to potential congestion collapse of the network.
在网络容量和最大流量得到很好控制的工程网络（例如，专用内联网）中，一些电话信令应用程序可能会选择放宽SCTP的拥塞控制规则，以满足定时要求。为了做到这一点，他们应该采用自己的拥塞控制机制。这必须在不破坏网络稳定的情况下进行；否则，可能会导致网络拥塞崩溃。
Some telephony signalling applications may have their own congestion control and flow control techniques. These techniques may interact with the congestion control procedures in SCTP.
一些电话信令应用可能有自己的拥塞控制和流量控制技术。这些技术可能与SCTP中的拥塞控制程序相互作用。
Often, telephony systems must have no single point of failure in operation.
通常，电话系统在运行中必须没有单点故障。
The UAL must meet certain service availability and performance requirements according to the classical signalling layers they are replacing. Those requirements may be specific for each UAL.
根据所取代的经典信令层，UAL必须满足特定的服务可用性和性能要求。这些要求可能针对每个UAL。
For example, telephony systems are often required to be able to preserve stable calls during a component failure. Therefore, error situations at the transport layer and below must be detected quickly so that the UAL can take appropriate steps to recover and preserve the calls. This poses special requirements on SCTP to discover unreachability of a destination address or a peer.
例如，电话系统通常需要能够在组件故障期间保持稳定的呼叫。因此，必须快速检测传输层及其以下的错误情况，以便UAL能够采取适当的步骤恢复和保留呼叫。这对SCTP提出了特殊要求，以发现目标地址或对等地址的不可访问性。
The SCTP protocol parameter RTO.Min value has a direct impact on the calculation of the RTO itself. Some telephony applications want to lower the value of the RTO.Min to less than 1 second. This would allow the message sender to reach the maximum number-of-retransmission threshold faster in the case of network failures. However, lowering RTO.Min may have a negative impact on network behaviour [ALLMAN99].
SCTP协议参数RTO.Min的值直接影响RTO本身的计算。一些电话应用程序希望将RTO.Min的值降低到1秒以下。这将允许消息发送方在网络故障的情况下更快地达到最大重传次数阈值。然而，降低RTO.Min可能会对网络行为产生负面影响[ALLMAN99]。
In some rare cases, telephony applications might not want to use the exponential timer back-off concept in RTO calculation in order to speed up failure detection. The danger of doing this is that, when network congestion occurs, not backing off the timer may worsen the congestion situation. Therefore, this strategy should never be used on the public Internet.
在某些罕见的情况下，电话应用程序可能不希望在RTO计算中使用指数计时器后退概念，以加快故障检测。这样做的危险在于，当网络拥塞发生时，不关闭计时器可能会使拥塞情况恶化。因此，这种策略不应该在公共互联网上使用。
It should be noted that not using delayed SACK will also increase the speed of failure detection.
应该注意的是，不使用延迟SACK也会提高故障检测的速度。
For faster detection of (un)availability of idle paths, the telephony application may consider lowering the SCTP parameter HB.interval. It should be noted this might result in a higher traffic load.
为了更快地检测空闲路径的可用性，电话应用可以考虑降低SCTP参数HB.间隔。应注意，这可能会导致更高的流量负载。
Setting Path.Max.Retrans and Association.Max.Retrans SCTP parameters to lower values will speed up both destination address and peer failure detection. However, if these values are set too low, the probability of false fault detections might increase.
将Path.Max.Retrans和Association.Max.Retrans SCTP参数设置为较低的值将加快目标地址和对等故障检测。但是，如果这些值设置得太低，错误故障检测的概率可能会增加。
Telephony applications often require short end-to-end message delays. The method described in Section 3.2.1 for lowering RTO may be considered. The different paths within a single association will have a different RTO, so using the path with the lowest RTO will lead to a shorter end-to-end message delay for the application running on top of the UALs.
电话应用程序通常需要短的端到端消息延迟。可考虑第3.2.1节中描述的降低RTO的方法。单个关联中的不同路径将具有不同的RTO，因此使用RTO最低的路径将导致在ALU上运行的应用程序的端到端消息延迟更短。
Bundling small telephony signalling messages at transmission helps improve the bandwidth usage efficiency of the network. On the downside, bundling may introduce additional delay to some of the messages. This should be taken into consideration when end-to-end delay is a concern.
在传输时捆绑小型电话信令消息有助于提高网络的带宽使用效率。另一方面，捆绑可能会给某些消息带来额外的延迟。当需要考虑端到端延迟时，应考虑这一点。
Telephony signalling traffic is often composed of multiple, independent message sequences. It is highly desirable to transfer those independent message sequences in separate SCTP streams. This reduces the probability of head-of-line blocking in which the retransmission of a lost message affects the delivery of other messages not belonging to the same message sequence.
电话信令业务通常由多个独立的消息序列组成。非常希望在单独的SCTP流中传输这些独立的消息序列。这降低了行首阻塞的概率，其中丢失消息的重新传输会影响不属于同一消息序列的其他消息的传递。
Users Adaptation Layers (UALs) are defined to encapsulate different signalling protocols for transport over SCTP/IP.
用户适配层（ALS）被定义为封装不同的信令协议，以便通过SCTP/IP进行传输。
There are UALs for both access signalling (DSS1) and trunk signalling (SS7). A brief description of the standardized UALs follows in the next sub-sections.
接入信令（DSS1）和中继信令（SS7）都有ALU。下一小节将简要介绍标准化的用户体验。
The delivery mechanism in several UALs supports:
多个平台中的交付机制支持：
o Seamless operation of UALs user peers over an IP network connection. o The interface boundary that the UAL user had with the traditional lower layer. o Management of SCTP transport associations and traffic between SGs and ISEPs or two ISEPs o Asynchronous reporting of status changes to management.
o 通过IP网络连接实现用户对等点的无缝操作。o UAL用户与传统底层的界面边界。o管理SGs和ISEP或两个ISEP之间的SCTP传输关联和通信量o向管理层异步报告状态更改。
Signalling User Adaptation Layers have been developed for both Access and Trunk Telephony Signalling. They are defined as follows.
已经为接入和中继电话信令开发了信令用户适配层。它们的定义如下。
Access Signalling: This is the signalling that is needed between an access device and an exchange in the core network in order to establish, manage, or release the voice or data call paths. Several protocols have been developed for this purpose.
接入信令：这是接入设备和核心网络中的交换机之间建立、管理或释放语音或数据呼叫路径所需的信令。为此目的已经制定了若干协议。
Trunk Signalling: This is the signalling that is used between the exchanges inside the core network in order to establish, manage, or release the voice or data call paths. The most common protocols used for this purpose are known as the SS7 system, which belongs to the Common Channel Signalling (CCS) philosophy. The SS7 protocol stack is depicted below:
中继信令：这是在核心网络内的交换机之间使用的信令，用于建立、管理或释放语音或数据呼叫路径。用于此目的的最常见协议称为SS7系统，它属于公共信道信令（CCS）原理。SS7协议栈如下所示：
+------+-----+-------+- -+-------+------+-----+------+
| | | | | | MAP | CAP | INAP |
+ | + RANAP |...| BSSAP +-------------------+
| ISUP | TUP | | | | TCAP |
+ | +---------------------------------------+
| | | SCCP |
+----------------------------------------------------+
| MTP3 |
+----------------------------------------------------+
| MTP2 |
+----------------------------------------------------+
| MTP1 |
+----------------------------------------------------+
+------+-----+-------+- -+-------+------+-----+------+
| | | | | | MAP | CAP | INAP |
+ | + RANAP |...| BSSAP +-------------------+
| ISUP | TUP | | | | TCAP |
+ | +---------------------------------------+
| | | SCCP |
+----------------------------------------------------+
| MTP3 |
+----------------------------------------------------+
| MTP2 |
+----------------------------------------------------+
| MTP1 |
+----------------------------------------------------+
Figure 2: SS7 Protocol Stack
图2:SS7协议栈
The Telephony Signalling Protocols to be transported with the already designed UALS are:
使用已设计的ALU传输的电话信令协议包括：
o ISDN Q.921 Users: Q.931 o V5.2/DSS1 o DPNSS/DASS2 [RFC4129] o SS7 MTP3 Users: SCCP, ISUP, TUP o SS7 MTP2 Users: MTP3 o SS7 SCCP Users: TCAP, RANAP, BSSAP, ...
o ISDN Q.921用户：Q.931 o V5.2/DSS1 o DPNSS/DASS2[RFC4129]o SS7 MTP3用户：SCCP、ISUP、TUP o SS7 MTP2用户：MTP3 o SS7 SCCP用户：TCAP、RANAP、BSSAP等。。。
Two main scenarios have been developed to use the different UALS for IP Signalling Transport:
已经开发了两个主要场景，以使用不同的ALU进行IP信令传输：
1. Intercommunication of traditional Signalling transport nodes and IP based nodes.
1. 传统信令传输节点与基于IP的节点的互通。
Traditional Telephony
Telephony Signalling
********* Signalling ********** over IP ********
* SEP *----------------* SG *--------------* ISEP *
********* ********** ********
Traditional Telephony
Telephony Signalling
********* Signalling ********** over IP ********
* SEP *----------------* SG *--------------* ISEP *
********* ********** ********
+-------+ +-------+
|SigProt| |SigProt|
+-------+ +----+----+ +-------+
| | | |UAL | | UAL |
| | | +----+ +-------+
| TTST | |TTST|SCTP| | SCTP |
| | | +----+ +-------+
| | | | IP | | IP |
+-------+ +---------+ +-------+
+-------+ +-------+
|SigProt| |SigProt|
+-------+ +----+----+ +-------+
| | | |UAL | | UAL |
| | | +----+ +-------+
| TTST | |TTST|SCTP| | SCTP |
| | | +----+ +-------+
| | | | IP | | IP |
+-------+ +---------+ +-------+
SEP - Signalling Endpoint SG - Signalling Gateway ISEP - IP Signalling Endpoint SigProt - Signalling Protocol TTSP - Traditional Telephony Signalling Protocol UAL - User Adaptation Layer SCTP - Stream Control Transport Protocol
SEP-信令端点SG-信令网关ISEP-IP信令端点SigProt-信令协议TTSP-传统电话信令协议UAL-用户适配层SCTP-流控制传输协议
Figure 3: General Architecture of SS7-IP Interworking
图3:SS7-IP互通的总体架构
This is also referred to as SG-to-AS communication. AS is the name that UAL usually gives to the ISEP nodes. It stands for Application Server.
这也称为SG通信。这是UAL通常给ISEP节点的名称。它代表应用服务器。
2. Communication inside the IP network.
2. IP网络内部的通信。
Telephony
Signalling
********* over IP *********
* ISEP *------------------* ISEP *
********* *********
Telephony
Signalling
********* over IP *********
* ISEP *------------------* ISEP *
********* *********
+-------+ +-------+
|SigProt| |SigProt|
+-------+ +-------+
| UAL | | UAL |
+-------+ +-------+
| SCTP | | SCTP |
+-------+ +-------+
| IP | | IP |
+-------+ +-------+
+-------+ +-------+
|SigProt| |SigProt|
+-------+ +-------+
| UAL | | UAL |
+-------+ +-------+
| SCTP | | SCTP |
+-------+ +-------+
| IP | | IP |
+-------+ +-------+
Figure 4: General Architecture of Intra-IP Communication
图4：IP内通信的一般架构
This is also referred to as IPSP communication. IPSP stands for IP Signalling Point and describes the role that the UAL plays on an IP-based node.
这也称为IPSP通信。IPSP代表IP信令点，描述了UAL在基于IP的节点上扮演的角色。
The first scenario is applied for both types of signalling (access and trunk signalling). On the other hand, the peer-to-peer basis can only be used for trunk signalling.
第一种情况适用于两种类型的信令（接入和中继信令）。另一方面，对等基础只能用于中继信令。
The SIGTRAN WG has developed UALs to transport the following Access Signalling protocols:
SIGTRAN WG开发了用于传输以下接入信令协议的ALU：
o ISDN Q.931 o V5.2 o DPNSS/DASS2
o ISDN Q.931 o V5.2 o DPNSS/DASS2
UAL: IUA (ISDN Q.921 User Adaptation)
UAL:IUA（ISDN Q.921用户自适应）
This document supports both ISDN Primary Rate Access (PRA) as well as Basic Rate Access (BRA) including the support for both point-to-point and point-to-multipoint modes of communication. This support includes Facility Associated Signalling (FAS), Non-Facility Associated Signalling (NFAS), and NFAS with backup D channel.
本文档支持ISDN主速率访问（PRA）和基本速率访问（BRA），包括对点对点和点对多点通信模式的支持。这种支持包括设施相关信令（FAS）、非设施相关信令（NFAS）和具有备用D通道的NFAS。
It implements the client/server architecture. The default orientation is for the SG to take on the role of server while the ISEP is the client. The SCTP (and UDP/TCP) Registered User Port Number Assignment for IUA is 9900.
它实现了客户机/服务器体系结构。默认方向是，当ISEP是客户机时，SG承担服务器角色。IUA的SCTP（和UDP/TCP）注册用户端口号分配为9900。
Examples of the upper layers to be transported are Q.931 and QSIG.
待运输的上层示例为Q.931和QSIG。
The main scenario supported by this UAL is the SG-to-ISP communication where the ISEP role is typically played by a node called an MGC, as defined in [RFC2719].
此UAL支持的主要场景是SG到ISP的通信，其中ISEP角色通常由称为MGC的节点扮演，如[RFC2719]中所定义。
****** ISDN ****** IP *******
*PBX *---------------* SG *--------------* MGC *
****** ****** *******
****** ISDN ****** IP *******
*PBX *---------------* SG *--------------* MGC *
****** ****** *******
+-----+ +-----+
|Q.931| (NIF) |Q.931|
+-----+ +----------+ +-----+
| | | | IUA| | IUA |
| | | +----+ +-----+
|Q.921| |Q.921|SCTP| |SCTP |
| | | +----+ +-----+
| | | | IP | | IP |
+-----+ +-----+----+ +-----+
+-----+ +-----+
|Q.931| (NIF) |Q.931|
+-----+ +----------+ +-----+
| | | | IUA| | IUA |
| | | +----+ +-----+
|Q.921| |Q.921|SCTP| |SCTP |
| | | +----+ +-----+
| | | | IP | | IP |
+-----+ +-----+----+ +-----+
NIF - Nodal Interworking Function PBX - Private Branch Exchange SCTP - Stream Control Transmission Protocol IUA - ISDN User Adaptation Layer Protocol
NIF-节点互通功能PBX-专用分支交换机SCTP-流控制传输协议IUA-ISDN用户适配层协议
Figure 5: ISDN-IP Interworking using IUA
图5：使用IUA的ISDN-IP互通
The SCTP (and UDP/TCP) Registered User Port Number Assignment for IUA is 9900.
IUA的SCTP（和UDP/TCP）注册用户端口号分配为9900。
The value assigned by IANA for the Payload Protocol Identifier in the SCTP Payload Data chunk is "1".
IANA为SCTP有效负载数据块中的有效负载协议标识符分配的值为“1”。
UAL: V5UA (V5.2-User Adaptation)
UAL:V5UA（V5.2-用户自适应）
V5UA is an extension from the IUA layer with the modifications needed to support the differences between Q.921/Q.931, and V5.2 layer 2/layer 3. It supports analog telephone access, ISDN basic rate access and ISDN primary rate access over a V5.2 interface. It is typically implemented in an interworking scenario with SG.
V5UA是IUA层的扩展，需要进行修改以支持Q.921/Q.931和V5.2第2层/第3层之间的差异。它通过V5.2接口支持模拟电话接入、ISDN基本速率接入和ISDN主要速率接入。它通常在与SG的互通场景中实现。
****** V5.2 ****** IP *******
* AN *---------------* SG *--------------* MGC *
****** ****** *******
****** V5.2 ****** IP *******
* AN *---------------* SG *--------------* MGC *
****** ****** *******
+-----+ +-----+
|V5.2 | (NIF) |V5.2 |
+-----+ +----------+ +-----+
| | | |V5UA| |V5UA |
| | | +----+ +-----+
|LAPV5| |LAPV5|SCTP| |SCTP |
| | | +----+ +-----+
| | | | IP + | IP |
+-----+ +-----+----+ +-----+
+-----+ +-----+
|V5.2 | (NIF) |V5.2 |
+-----+ +----------+ +-----+
| | | |V5UA| |V5UA |
| | | +----+ +-----+
|LAPV5| |LAPV5|SCTP| |SCTP |
| | | +----+ +-----+
| | | | IP + | IP |
+-----+ +-----+----+ +-----+
AN - Access Network NIF - Nodal Interworking Function LAPV5 - Link Access Protocol for the V5 channel SCTP - Stream Control Transmission Protocol
AN-接入网NIF-节点互通功能LAPV5-V5信道SCTP的链路接入协议-流控制传输协议
Figure 6: V5.2-IP Interworking using V5UA
图6：使用V5UA的V5.2-IP互通
The SCTP (and UDP/TCP) Registered User Port Number Assignment for V5UA is 5675.
V5UA的SCTP（和UDP/TCP）注册用户端口号分配为5675。
The value assigned by IANA for the Payload Protocol Identifier in the SCTP Payload Data chunk is "6".
IANA为SCTP有效负载数据块中的有效负载协议标识符分配的值为“6”。
UAL: DUA (DPNSS/DASS2 User Adaptation)
UAL:DUA（DPNSS/DASS2用户自适应）
The DUA is built on top of IUA and defines the necessary extensions to IUA for a DPNSS/DASS2 transport. DPNSS stands for Digital Private Network Signalling System and DASS2 for Digital Access Signalling System 2.
DUA构建在IUA之上，定义了DPNSS/DASS2传输对IUA的必要扩展。DPNSS代表数字专用网信令系统，DASS2代表数字接入信令系统2。
****** DPNSS ****** IP *******
*PBX *---------------* SG *--------------* MGC *
****** ****** *******
****** DPNSS ****** IP *******
*PBX *---------------* SG *--------------* MGC *
****** ****** *******
+-----+ +-----+
|DPNSS| (NIF) |DPNSS|
| L3 | | L3 |
+-----+ +-----+----+ +-----+
| | | | DUA| | DUA |
|DPNSS| |DPNSS+----+ +-----+
| L2 | | L2 |SCTP| |SCTP |
| | | +----+ +-----+
| | | | IP + | IP |
+-----+ +-----+----+ +-----+
+-----+ +-----+
|DPNSS| (NIF) |DPNSS|
| L3 | | L3 |
+-----+ +-----+----+ +-----+
| | | | DUA| | DUA |
|DPNSS| |DPNSS+----+ +-----+
| L2 | | L2 |SCTP| |SCTP |
| | | +----+ +-----+
| | | | IP + | IP |
+-----+ +-----+----+ +-----+
PBX - Private Branch eXchange NIF - Nodal Interworking Function SCTP - Stream Control Transmission Protocol DUA - DPNSS User Adaptation Layer Protocol
PBX-专用分支交换机NIF-节点互通功能SCTP-流控制传输协议DUA-DPNSS用户适配层协议
Figure 7: DPNSS-IP Interworking using DUA
图7：使用DUA的DPNSS-IP互通
The value assigned by IANA for the Payload Protocol Identifier in the SCTP Payload Data chunk is "10". .
IANA为SCTP有效负载数据块中的有效负载协议标识符分配的值为“10”。
The SIGTRAN WG has developed UALs to transport the following SS7 protocols:
SIGTRAN WG已开发了用于传输以下SS7协议的ALS：
o MTP2 Users: MTP3 o MTP3 Users: ISUP, TUP, SCCP o SCCP Users: TCAP, RNSAP, RANAP, BSSAP, ...
o MTP2用户：MTP3 o MTP3用户：ISUP、TUP、SCCP o SCCP用户：TCAP、RNSAP、RANAP、BSSAP等。。。
UALs:
圣歌：
o M2UA (SS7 MTP2 User Adaptation [RFC3331]) o M2PA (SS7 MTP2-User Peer-to-Peer Adaptation [RFC4165])
o M2UA（SS7 MTP2用户自适应[RFC3331]）o M2PA（SS7 MTP2用户对等自适应[RFC4165]）
M2UA protocol is typically used between a Signalling Gateway (SG) and Media Gateway Controller (MGC). The SG will terminate up to MTP Level 2, and the MGC will terminate MTP Level 3 and above. In other words, the SG will transport MTP Level 3 messages over an IP network to an MGC.
M2UA协议通常用于信令网关（SG）和媒体网关控制器（MGC）之间。SG将终止至MTP 2级，MGC将终止MTP 3级及以上。换句话说，SG将通过IP网络将MTP级别3消息传输到MGC。
MTP3 and MTP3b are the only SS7 MTP2 User protocols that are transported by this UAL.
MTP3和MTP3b是此UAL传输的唯一SS7 MTP2用户协议。
The SG provides an interworking of transport functions with the IP transport to transfer MTP2-User signalling messages with an Application Server (e.g., MGC) where the peer MTP2-User exists.
SG提供传输功能与IP传输的互通，以将MTP2用户信令消息传输到存在对等MTP2用户的应用服务器（例如MGC）。
****** SS7 ****** IP *******
*SEP *-----------* SG *-------------* MGC *
****** ****** *******
****** SS7 ****** IP *******
*SEP *-----------* SG *-------------* MGC *
****** ****** *******
+----+ +----+
|S7UP| |S7UP|
+----+ +----+
|MTP3| |MTP3|
| | (NIF) | |
+----+ +----+----+ +----+
| | | |M2UA| |M2UA|
| | | +----+ +----+
|MTP2| |MTP2|SCTP| |SCTP|
| | | +----+ +----+
| | | |IP | |IP |
+----+ +---------+ +----+
+----+ +----+
|S7UP| |S7UP|
+----+ +----+
|MTP3| |MTP3|
| | (NIF) | |
+----+ +----+----+ +----+
| | | |M2UA| |M2UA|
| | | +----+ +----+
|MTP2| |MTP2|SCTP| |SCTP|
| | | +----+ +----+
| | | |IP | |IP |
+----+ +---------+ +----+
MGC - Media Gateway Controller SG - Signalling Gateway SEP - SS7 Signalling Endpoint NIF - Nodal Interworking Function IP - Internet Protocol SCTP - Stream Control Transmission Protocol
MGC-媒体网关控制器SG-信令网关SEP-SS7信令端点NIF-节点互通功能IP-互联网协议SCTP-流控制传输协议
Figure 8: SS7-IP Interworking using M2UA
图8：使用M2UA的SS7-IP互通
The SCTP (and UDP/TCP) Registered User Port Number Assignment for M2UA is 2904.
M2UA的SCTP（和UDP/TCP）注册用户端口号分配为2904。
The value assigned by IANA for the Payload Protocol Identifier in the SCTP Payload Data chunk is "2".
IANA为SCTP有效负载数据块中的有效负载协议标识符分配的值为“2”。
M2PA protocol is used between SS7 Signalling Points employing the MTP Level 3 protocol. The SS7 Signalling Points may also use standard SS7 links using the SS7 MTP Level 2 to provide transport of MTP Level 3 signalling messages.
M2PA协议在采用MTP 3级协议的SS7信令点之间使用。SS7信令点还可以使用使用SS7 MTP级别2的标准SS7链路来提供MTP级别3信令消息的传输。
Both configurations: communication of SS7 and IP with SG and communication between ISEPs are possible.
两种配置：SS7和IP与SG的通信以及ISEP之间的通信都是可能的。
Connection of SS7 and IP nodes:
SS7和IP节点的连接：
******** SS7 *************** IP ********
* SEP *--------* SG *--------* IPSP *
******** *************** ********
******** SS7 *************** IP ********
* SEP *--------* SG *--------* IPSP *
******** *************** ********
+------+ +------+
| TCAP | | TCAP |
+------+ +------+
| SCCP | | SCCP |
+------+ +-------------+ +------+
| MTP3 | | MTP3 | | MTP3 |
+------+ +------+------+ +------+
| | | | M2PA | | M2PA |
| | | +------+ +------+
| MTP2 | | MTP2 | SCTP | | SCTP |
| | | +------+ +------+
| | | | IP | | IP |
+------+ +------+------+ +------+
+------+ +------+
| TCAP | | TCAP |
+------+ +------+
| SCCP | | SCCP |
+------+ +-------------+ +------+
| MTP3 | | MTP3 | | MTP3 |
+------+ +------+------+ +------+
| | | | M2PA | | M2PA |
| | | +------+ +------+
| MTP2 | | MTP2 | SCTP | | SCTP |
| | | +------+ +------+
| | | | IP | | IP |
+------+ +------+------+ +------+
SEP - SS7 Signalling Endpoint
SEP-SS7信令端点
Figure 9: SS7-IP Interworking with M2PA
图9:SS7-IP与M2PA互通
Communication between two IP nodes:
两个IP节点之间的通信：
******** IP ********
* IPSP *--------* IPSP *
******** ********
******** IP ********
* IPSP *--------* IPSP *
******** ********
+------+ +------+
| TCAP | | TCAP |
+------+ +------+
| SCCP | | SCCP |
+------+ +------+
| MTP3 | | MTP3 |
+------+ +------+
| M2PA | | M2PA |
+------+ +------+
| SCTP | | SCTP |
+------+ +------+
| IP | | IP |
+------+ +------+
+------+ +------+
| TCAP | | TCAP |
+------+ +------+
| SCCP | | SCCP |
+------+ +------+
| MTP3 | | MTP3 |
+------+ +------+
| M2PA | | M2PA |
+------+ +------+
| SCTP | | SCTP |
+------+ +------+
| IP | | IP |
+------+ +------+
IP - Internet Protocol IPSP - IP Signalling Point SCTP - Stream Control Transmission Protocol
IP-互联网协议IPSP-IP信令点SCTP-流控制传输协议
Figure 10: Intra-IP Communication using M2PA
图10：使用M2PA的IP内通信
These figures are only an example. Other configurations are possible. For example, IPSPs without traditional SS7 links could use the protocol layers MTP3/M2PA/SCTP/IP to route SS7 messages in a network with all IP links.
这些数字只是一个例子。其他配置也是可能的。例如，没有传统SS7链路的IPSP可以使用协议层MTP3/M2PA/SCTP/IP在具有所有IP链路的网络中路由SS7消息。
Another example is that two SGs could be connected over an IP network to form an SG mated pair, similar to the way STPs are provisioned in traditional SS7 networks.
另一个例子是，两个SG可以通过IP网络连接以形成SG配对，类似于传统SS7网络中供应stp的方式。
The SCTP (and UDP/TCP) Registered User Port Number Assignment for M2PA is 3565.
M2PA的SCTP（和UDP/TCP）注册用户端口号分配为3565。
The value assigned by IANA for the Payload Protocol Identifier in the SCTP Payload Data chunk is "5".
IANA为SCTP有效负载数据块中的有效负载协议标识符分配的值为“5”。
o M2PA: IPSP processes MTP3/MTP2 primitives. o M2UA: MGC transports MTP3/MTP2 primitives between the SG's MTP2 and the MGC's MTP3 (via the NIF) for processing. o M2PA: SG-IPSP connection is an SS7 link. o M2UA: SG-MGC connection is not an SS7 link. It is an extension of MTP to a remote entity.
o M2PA:IPSP处理MTP3/MTP2原语。o M2UA:MGC在SG的MTP2和MGC的MTP3之间传输MTP3/MTP2原语（通过NIF）进行处理。o M2PA:SG-IPSP连接是SS7链路。o M2UA:SG-MGC连接不是SS7链路。它是MTP对远程实体的扩展。
UAL: M3UA (SS7 MTP3 User Adaptation)
UAL:M3UA（SS7 MTP3用户自适应）
M3UA protocol supports the transport of any SS7 MTP3-User signalling such as TUP, ISUP, and SCCP over IP using the services of SCTP.
M3UA协议支持使用SCTP服务通过IP传输任何SS7 MTP3用户信令，如TUP、ISUP和SCCP。
Interconnection of SS7 and IP nodes:
SS7和IP节点的互连：
******** SS7 ***************** IP ********
* SEP *---------* SGP *--------* ASP *
******** ***************** ********
******** SS7 ***************** IP ********
* SEP *---------* SGP *--------* ASP *
******** ***************** ********
+------+ +---------------+ +------+
| ISUP | | (NIF) | | ISUP |
+------+ +------+ +------+ +------+
| MTP3 | | MTP3 | | M3UA | | M3UA |
+------| +------+-+------+ +------+
| MTP2 | | MTP2 | | SCTP | | SCTP |
+------+ +------+ +------+ +------+
| L1 | | L1 | | IP | | IP |
+------+ +------+ +------+ +------+
+------+ +---------------+ +------+
| ISUP | | (NIF) | | ISUP |
+------+ +------+ +------+ +------+
| MTP3 | | MTP3 | | M3UA | | M3UA |
+------| +------+-+------+ +------+
| MTP2 | | MTP2 | | SCTP | | SCTP |
+------+ +------+ +------+ +------+
| L1 | | L1 | | IP | | IP |
+------+ +------+ +------+ +------+
SEP - SS7 Signalling End Point SCTP - Stream Control Transmission Protocol NIF - Nodal Interworking Function
SEP-SS7信令端点SCTP-流控制传输协议NIF-节点互通功能
Figure 11: SS7-IP Interworking using M3UA
图11：使用M3UA的SS7-IP互通
Communication between two IP nodes:
两个IP节点之间的通信：
******** IP ********
* IPSP *----------* IPSP *
******** ********
******** IP ********
* IPSP *----------* IPSP *
******** ********
+------+ +------+
|SCCP- | |SCCP- |
| User | | User |
+------+ +------+
| SCCP | | SCCP |
+------+ +------+
| M3UA | | M3UA |
+------+ +------+
| SCTP | | SCTP |
+------+ +------+
| IP | | IP |
+------+ +------+
+------+ +------+
|SCCP- | |SCCP- |
| User | | User |
+------+ +------+
| SCCP | | SCCP |
+------+ +------+
| M3UA | | M3UA |
+------+ +------+
| SCTP | | SCTP |
+------+ +------+
| IP | | IP |
+------+ +------+
Figure 12: Intra-IP Communication using M3UA
图12：使用M3UA的IP内通信
M3UA uses a client-server architecture. It is recommended that the ISEP acts as the client and initiate the SCTP associations with the SG. The port reserved by IANA is 2905. This is the port upon which the SG should listen for possible client connections.
M3UA使用客户机-服务器体系结构。建议ISEP充当客户机，并启动与SG的SCTP关联。IANA保留的端口为2905。这是SG应侦听可能的客户端连接的端口。
The assigned payload protocol identifier for the SCTP DATA chunks is "3".
为SCTP数据块分配的有效负载协议标识符为“3”。
UAL: SUA (SS7 SCCP User Adaptation)
UAL:SUA（SS7 SCCP用户自适应）
SUA protocol supports the transport of any SS7 SCCP-User signalling such as MAP, INAP, SMS, BSSAP, or RANAP over IP using the services of SCTP. Each of the applications using SUA has its own set of timing requirements that can be found in its respective standards documents.
SUA协议支持使用SCTP服务通过IP传输任何SS7 SCCP用户信令，如MAP、INAP、SMS、BSSAP或RANAP。使用SUA的每个应用程序都有自己的一组时间要求，可以在各自的标准文档中找到。
Possible configurations are showed in the pictures below.
可能的配置如下图所示。
- Interconnection of SS7 and IP:
- 七号信令与IP的互连：
******** *************** ********
* SEP * SS7 * * IP * *
* or *---------* SG *--------* ASP *
* STP * * * * *
******** *************** ********
******** *************** ********
* SEP * SS7 * * IP * *
* or *---------* SG *--------* ASP *
* STP * * * * *
******** *************** ********
+------ +------+
| SUAP | | SUAP |
+------+ +------+------+ +------+
| SCCP | | SCCP | SUA | | SUA |
+------+ +------+------+ +------+
| | | | | | |
| MTP3 | | MTP3 | SCTP | | SCTP |
| | | | | | |
+------+ +------+------+ +------+
| MTP2 | | MTP2 | IP | | IP |
+------+ +------+------+ +------+
+------ +------+
| SUAP | | SUAP |
+------+ +------+------+ +------+
| SCCP | | SCCP | SUA | | SUA |
+------+ +------+------+ +------+
| | | | | | |
| MTP3 | | MTP3 | SCTP | | SCTP |
| | | | | | |
+------+ +------+------+ +------+
| MTP2 | | MTP2 | IP | | IP |
+------+ +------+------+ +------+
SUAP - SCCP/SUA User Protocol (TCAP, for example) STP - SS7 Signalling Transfer Point
SUAP-SCCP/SUA用户协议（例如TCAP）STP-SS7信令传输点
Figure 13: SS7-IP Interworking using SUA
图13：使用SUA的SS7-IP互通
- IP Node to IP Node communication:
- IP节点到IP节点的通信：
******** ********
* * IP * *
* IPSP *--------* IPSP *
* * * *
******** ********
******** ********
* * IP * *
* IPSP *--------* IPSP *
* * * *
******** ********
+------+ +------+
| SUAP | | SUAP |
+------+ +------+
| SUA | | SUA |
+------+ +------+
| SCTP | | SCTP |
+------+ +------+
| IP | | IP |
+------+ +------+
+------+ +------+
| SUAP | | SUAP |
+------+ +------+
| SUA | | SUA |
+------+ +------+
| SCTP | | SCTP |
+------+ +------+
| IP | | IP |
+------+ +------+
Figure 14: Intra-IP Communication using SUA
图14：使用SUA的IP内通信
IANA has registered SCTP Port Number 14001 for SUA. It is recommended that SGs use this SCTP port number for listening for new connections. The payload protocol identifier for the SCTP DATA chunks is "4".
IANA已为SUA注册了SCTP端口号14001。建议SGs使用此SCTP端口号侦听新连接。SCTP数据块的有效负载协议标识符为“4”。
UALs are designated to carry signalling messages for telephony services. As such, UALs must involve the security needs of several parties: the end users of the services, the network providers, and the applications involved. Additional requirements may come from local regulation. Although some security needs overlap, any security solution should fulfill all the different parties' needs. See specific Security Considerations in each UAL Technical specification for details (for general security principles of SIGTRAN, see [RFC3788]).
ALU被指定为承载电话服务的信令消息。因此，ALU必须涉及多方的安全需求：服务的最终用户、网络提供商和相关应用程序。其他要求可能来自当地法规。尽管有些安全需求重叠，但任何安全解决方案都应该满足所有不同方的需求。有关详细信息，请参见各UAL技术规范中的具体安全注意事项（有关SIGTRAN的一般安全原则，请参见[RFC3788]）。
SCTP only tries to increase the availability of a network. SCTP does not contain any protocol mechanisms directly related to communication security, i.e., user message authentication, integrity, or confidentiality functions. For such features, SCTP depends on security protocols. In the field of system security, SCTP includes mechanisms for reducing the risk of blind denial-of-service attacks as described in Section 11 of [RFC2960].
SCTP仅尝试提高网络的可用性。SCTP不包含任何与通信安全直接相关的协议机制，即用户消息身份验证、完整性或保密功能。对于这些特性，SCTP依赖于安全协议。在系统安全领域，SCTP包括降低盲拒绝服务攻击风险的机制，如[RFC2960]第11节所述。
This document does not add any new components to the protocols included in the discussion. For secure use of the SIGTRAN protocols, readers should go through the "Security Considerations for SIGTRAN Protocols" [RFC3788]). According to that document, the use of the IPsec is the main requirement to secure SIGTRAN protocols in the Internet, but Transport Layer Security (TLS) is also considered a perfectly valid option for use in certain scenarios (see [RFC3436] for more information on using TLS with SCTP). Recommendations of usage are also included.
本文档不会向讨论中包含的协议添加任何新组件。为了安全使用SIGTRAN协议，读者应阅读“SIGTRAN协议的安全注意事项”[RFC3788]）。根据该文件，使用IPsec是在Internet上保护SIGTRAN协议的主要要求，但传输层安全性（TLS）也被认为是在某些场景中使用的完全有效的选项（有关将TLS与SCTP一起使用的更多信息，请参阅[RFC3436]）。还包括使用建议。
[ALLMAN99] Allman, M. and V. Paxson, "On Estimating End-to-End Network Path Properties", Proc. SIGCOMM'99, 1999.
[ALLMAN99]Allman，M.和V.Paxson，“关于估算端到端网络路径属性”，Proc。SIGCOMM'991999。
[RFC2960] Stewart, R., Xie, Q., Morneault, K., Sharp, C., Schwarzbauer, H., Taylor, T., Rytina, I., Kalla, M., Zhang, L., and V. Paxson, "Stream Control Transmission Protocol", RFC 2960, October 2000.
[RFC2960]Stewart，R.，Xie，Q.，Morneault，K.，Sharp，C.，Schwarzbauer，H.，Taylor，T.，Rytina，I.，Kalla，M.，Zhang，L.，和V.Paxson，“流控制传输协议”，RFC 29602000年10月。
[RFC3257] Coene, L., "Stream Control Transmission Protocol Applicability Statement", RFC 3257, April 2002.
[RFC3257]Coene，L.，“流控制传输协议适用性声明”，RFC 3257，2002年4月。
[RFC2719] Ong, L., Rytina, I., Garcia, M., Schwarzbauer, H., Coene, L., Lin, H., Juhasz, I., Holdrege, M., and C. Sharp, "Framework Architecture for Signaling Transport", RFC 2719, October 1999.
[RFC2719]Ong，L.，Rytina，I.，Garcia，M.，Schwarzbauer，H.，Coene，L.，Lin，H.，Juhasz，I.，Holdrege，M.，和C.Sharp，“信号传输的框架架构”，RFC 2719，1999年10月。
[RFC3057] Morneault, K., Rengasami, S., Kalla, M., and G. Sidebottom, "ISDN Q.921-User Adaptation Layer", RFC 3057, February 2001.
[RFC3057]Morneault，K.，Rengasami，S.，Kalla，M.，和G.Sidebottom，“ISDN Q.921-用户适配层”，RFC 3057，2001年2月。
[RFC3331] Morneault, K., Dantu, R., Sidebottom, G., Bidulock, B., and J. Heitz, "Signaling System 7 (SS7) Message Transfer Part 2 (MTP2) - User Adaptation Layer", RFC 3331, September 2002.
[RFC3331]Morneault，K.，Dantu，R.，Sidebottom，G.，Bidulock，B.，和J.Heitz，“信令系统7（SS7）消息传输第2部分（MTP2）-用户适配层”，RFC 33312002年9月。
[RFC3332] Sidebottom, G., Morneault, K., and J. Pastor-Balbas, "Signaling System 7 (SS7) Message Transfer Part 3 (MTP3) - User Adaptation Layer (M3UA)", RFC 3332, September 2002.
[RFC3332]Sidebottom，G.，Morneault，K.，和J.Pastor Balbas，“信令系统7（SS7）消息传输部分3（MTP3）-用户适配层（M3UA）”，RFC 33322002年9月。
[RFC3436] Jungmaier, A., Rescorla, E., and M. Tuexen, "Transport Layer Security over Stream Control Transmission Protocol", RFC 3436, December 2002.
[RFC3436]Jungmaier，A.，Rescorla，E.，和M.Tuexen，“流控制传输协议上的传输层安全”，RFC 3436，2002年12月。
[RFC3868] Loughney, J., Sidebottom, G., Coene, L., Verwimp, G., Keller, J., and B. Bidulock, "Signalling Connection Control Part User Adaptation Layer (SUA)", RFC 3868, October 2004.
[RFC3868]Loughney，J.，Sidebottom，G.，Coene，L.，Verwimp，G.，Keller，J.，和B.Bidulock，“信令连接控制部分用户适配层（SUA）”，RFC 38682004年10月。
[RFC4165] George, T., Dantu, R., Kalla, M., Schwarzbauer, H.J., Sidebottom, G., Morneault, K.,"SS7 MTP2-User Peer-to-Peer Adaptation Layer", RFC 4165, September 2005.
[RFC4165]George，T.，Dantu，R.，Kalla，M.，Schwarzbauer，H.J.，Sidebottom，G.，Morneault，K.，“SS7 MTP2用户点对点适配层”，RFC 41652005年9月。
[RFC3807] Weilandt, E., Khanchandani, N., and S. Rao, "V5.2-User Adaptation Layer (V5UA)", RFC 3807, June 2004.
[RFC3807]Weilandt，E.，Khanchandani，N.，和S.Rao，“V5.2-用户适配层（V5UA）”，RFC 3807，2004年6月。
[RFC4129] Mukundan, R., Morneault, K., and N. Mangalpally, "Digital Private Network Signaling System (DPNSS)/Digital Access Signaling System 2 (DASS 2) Extensions to the IUA Protocol", RFC 4129, September 2005.
[RFC4129]Mukundan，R.，Morneault，K.，和N.Mangalpally，“数字专用网络信令系统（DPNSS）/数字接入信令系统2（DASS 2）对IUA协议的扩展”，RFC 41292005年9月。
[RFC3788] Loughney, J., Tuexen, M., and J. Pastor-Balbas, "Security Considerations for Signaling Transport (SIGTRAN) Protocols", RFC 3788, June 2004.
[RFC3788]Loughney，J.，Tuexen，M.，和J.Pastor Balbas，“信号传输（SIGTRAN）协议的安全考虑”，RFC 3788，2004年6月。
Authors' Addresses
作者地址
Lode Coene Siemens Atealaan 34 Herentals B-2200 Belgium
Lode Coene Siemens Atalaan 34 Herentals B-2200比利时
Phone: +32-14-252081
EMail: lode.coene@siemens.com
Phone: +32-14-252081
EMail: lode.coene@siemens.com
Javier Pastor-Balbas Ericsson Via de los Poblados 13 Madrid 28033 Spain
Javier Pastor Balbas Ericsson Via de los Poblados 13马德里28033西班牙
Phone: +34 91 339 1397
EMail: J.Javier.Pastor@ericsson.com
Phone: +34 91 339 1397
EMail: J.Javier.Pastor@ericsson.com
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