Network Working Group J. Soininen, Ed.
Request for Comments: 3574 Nokia
Category: Informational August 2003
Network Working Group J. Soininen, Ed.
Request for Comments: 3574 Nokia
Category: Informational August 2003
Transition Scenarios for 3GPP Networks
3GPP网络的过渡场景
Status of this Memo
本备忘录的状况
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 (2003). All Rights Reserved.
版权所有（C）互联网协会（2003年）。版权所有。
Abstract
摘要
This document describes different scenarios in Third Generation Partnership Project (3GPP) defined packet network, i.e., General Packet Radio Service (GPRS) that would need IP version 6 and IP version 4 transition. The focus of this document is on the scenarios where the User Equipment (UE) connects to nodes in other networks, e.g., in the Internet. GPRS network internal transition scenarios, i.e., between different GPRS elements in the network, are out of scope. The purpose of the document is to list the scenarios for further discussion and study.
本文档描述了第三代合作伙伴计划（3GPP）定义的分组网络中的不同场景，即需要IP版本6和IP版本4转换的通用分组无线业务（GPRS）。本文档的重点是用户设备（UE）连接到其他网络（例如互联网）中的节点的场景。GPRS网络内部过渡场景（即网络中不同GPRS元素之间的过渡场景）超出范围。本文件的目的是列出供进一步讨论和研究的场景。
Table of Contents
目录
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Scope of the Document. . . . . . . . . . . . . . . . . . . . . 2
3. Brief Description of the 3GPP Network Environment. . . . . . . 2
3.1 GPRS Architecture Basics . . . . . . . . . . . . . . . . . 3
3.2 IP Multimedia Core Network Subsystem (IMS) . . . . . . . . 3
4. Transition Scenarios . . . . . . . . . . . . . . . . . . . . . 5
4.1 GPRS Scenarios . . . . . . . . . . . . . . . . . . . . . . 5
4.2 IMS Scenarios . . . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations. . . . . . . . . . . . . . . . . . . . 9
6. Contributing Authors . . . . . . . . . . . . . . . . . . . . . 10
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.1. Normative References . . . . . . . . . . . . . . . . . . 10
8.2. Informative References . . . . . . . . . . . . . . . . . 11
9. Editor's Address . . . . . . . . . . . . . . . . . . . . . . . 11
10. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 12
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Scope of the Document. . . . . . . . . . . . . . . . . . . . . 2
3. Brief Description of the 3GPP Network Environment. . . . . . . 2
3.1 GPRS Architecture Basics . . . . . . . . . . . . . . . . . 3
3.2 IP Multimedia Core Network Subsystem (IMS) . . . . . . . . 3
4. Transition Scenarios . . . . . . . . . . . . . . . . . . . . . 5
4.1 GPRS Scenarios . . . . . . . . . . . . . . . . . . . . . . 5
4.2 IMS Scenarios . . . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations. . . . . . . . . . . . . . . . . . . . 9
6. Contributing Authors . . . . . . . . . . . . . . . . . . . . . 10
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.1. Normative References . . . . . . . . . . . . . . . . . . 10
8.2. Informative References . . . . . . . . . . . . . . . . . 11
9. Editor's Address . . . . . . . . . . . . . . . . . . . . . . . 11
10. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 12
This document describes the transition scenarios in 3GPP packet data networks that might come up in the deployment phase of IPv6. The main purpose of this document is to identify and to document those scenarios for further discussion and study them in the v6ops working group.
本文档描述了在IPv6部署阶段可能出现的3GPP分组数据网络中的过渡场景。本文件的主要目的是确定和记录这些场景，供v6ops工作组进一步讨论和研究。
Just a brief overview of the 3GPP packet data network, GPRS, is given to help the reader to better understand the transition scenarios. A better overview of the 3GPP specified GPRS can be found for example from [6]. The GPRS architecture is defined in [1].
本文仅对3GPP分组数据网络GPRS进行简要概述，以帮助读者更好地理解过渡场景。例如，可以从[6]中找到有关3GPP指定GPRS的更好概述。[1]中定义了GPRS体系结构。
The scope is to describe the possible transition scenarios in the 3GPP defined GPRS network where a UE connects to, or is contacted from, the Internet or another UE. The document describes scenarios with and without the usage of the SIP-based (Session Initiation Protocol [5]) IP Multimedia Core Network Subsystem (IMS). The 3GPP releases 1999, 4, and 5 are considered as the basis.
范围是描述3GPP定义的GPRS网络中可能的过渡场景，其中UE连接到互联网或另一UE，或者从互联网或另一UE联系。本文档描述了使用和不使用基于SIP（会话启动协议[5]）的IP多媒体核心网络子系统（IMS）的场景。3GPP版本1999、4和5被视为基础。
Out of scope are scenarios inside the GPRS network, i.e., on the different interfaces of the GPRS network. This document neither changes 3GPP specifications, nor proposes changes to the current specifications.
超出范围的是GPRS网络内部的场景，即GPRS网络的不同接口。本文档既不更改3GPP规范，也不建议更改当前规范。
In addition, the possible transition scenarios are described. The solutions will be documented in a separate document.
此外，还描述了可能的过渡场景。解决方案将记录在单独的文件中。
All the possible scenarios are listed here. Further analysis may show that some of the scenarios are not actually relevant in this context.
这里列出了所有可能的场景。进一步的分析可能表明，某些场景在这种情况下实际上并不相关。
This section describes the most important concepts of the 3GPP environment for understanding the transition scenarios. The first part of the description gives a brief overview to the GPRS network as such. The second part concentrates on the IP Multimedia Core Network Subsystem (IMS).
本节描述了3GPP环境中用于理解过渡场景的最重要概念。描述的第一部分简要概述了GPRS网络。第二部分是IP多媒体核心网络子系统（IMS）。
This section gives an overview to the most important concepts of the 3GPP packet architecture. For more detailed description, please see [1].
本节概述3GPP分组体系结构的最重要概念。有关详细说明，请参见[1]。
From the point of view of this document, the most relevant 3GPP architectural elements are the User Equipment (UE), and the Gateway GPRS Support Node (GGSN). A simplified picture of the architecture is shown in Figure 1.
从本文档的角度来看，最相关的3GPP架构元素是用户设备（UE）和网关GPRS支持节点（GGSN）。架构的简化图如图1所示。
The UE is the mobile phone. It can either be an integrated device comprising a combined GPRS part, and the IP stack, or it might be a separate GPRS device, and separate equipment with the IP stack, e.g., a laptop.
UE是移动电话。它可以是包含组合GPRS部分和IP堆栈的集成设备，也可以是单独的GPRS设备和带有IP堆栈的单独设备，例如笔记本电脑。
The GGSN serves as an anchor-point for the GPRS mobility management. It also serves as the default router for the UE.
GGSN作为GPRS移动性管理的定位点。它还充当UE的默认路由器。
The Peer node mentioned in the picture refers to a node with which the UE is communicating.
图中提到的对等节点是指UE正在与之通信的节点。
-- ---- ************ ---------
|UE|- ... -|GGSN|--+--* IPv4/v6 NW *--+--|Peer node|
-- ---- ************ ---------
-- ---- ************ ---------
|UE|- ... -|GGSN|--+--* IPv4/v6 NW *--+--|Peer node|
-- ---- ************ ---------
Figure 1: Simplified GPRS Architecture
图1：简化的GPRS架构
There is a dedicated link between the UE and the GGSN called the Packet Data Protocol (PDP) Context. This link is created through the PDP Context activation process. During the activation the UE is configured with its IP address and other information needed to maintain IP access, e.g., DNS server address. There are three different types of PDP Contexts: IPv4, IPv6, and Point-to-Point Protocol (PPP).
在UE和GGSN之间有一个专用链路，称为分组数据协议（PDP）上下文。此链接通过PDP上下文激活过程创建。在激活期间，UE被配置有其IP地址和维持IP访问所需的其他信息，例如DNS服务器地址。PDP上下文有三种不同类型：IPv4、IPv6和点对点协议（PPP）。
A UE can have one or more simultaneous PDP Contexts open to the same or to different GGSNs. The PDP Context can be either of the same or different types.
UE可以具有对相同或不同ggsn开放的一个或多个同时的PDP上下文。PDP上下文可以是相同的或不同的类型。
IP Multimedia Core Network Subsystem (IMS) is an architecture for supporting multimedia services via a SIP infrastructure. It is specified in 3GPP Release 5. This section provides an overview of the 3GPP IMS and is not intended to be comprehensive. A more detailed description can be found in [2], [3] and [4].
IP多媒体核心网络子系统（IMS）是一种通过SIP基础设施支持多媒体服务的体系结构。它在3GPP版本5中指定。本节概述了3GPP IMS，并不打算全面。更详细的说明见[2]、[3]和[4]。
The IMS comprises a set of SIP proxies, servers, and registrars. In addition, there are Media Gateways (MGWs) that offer connections to non-IP networks such as the Public Switched Telephony Network (PSTN). A simplified overview of the IMS is depicted in figure 2.
IMS包括一组SIP代理、服务器和注册器。此外，还有媒体网关（MGW），提供到非IP网络（如公共交换电话网（PSTN））的连接。图2中描述了IMS的简化概述。
+-------------+ +-------------------------------------+
| | | +------+ |
| | | |S-CSCF|---
| | | | +------+ |
+-|+ | | | / |
| | | SIP Sig. | | +------+ +------+ |
| |----|------+------|--|----|P-CSCF|----------|I-CSCF| |
| | | | | +------+ +------+ |
| |-----------+------------------------------------------------
+--+ | User traf. | | |
UE | | | |
| GPRS access | | IP Multimedia CN Subsystem |
+-------------+ +-------------------------------------+
+-------------+ +-------------------------------------+
| | | +------+ |
| | | |S-CSCF|---
| | | | +------+ |
+-|+ | | | / |
| | | SIP Sig. | | +------+ +------+ |
| |----|------+------|--|----|P-CSCF|----------|I-CSCF| |
| | | | | +------+ +------+ |
| |-----------+------------------------------------------------
+--+ | User traf. | | |
UE | | | |
| GPRS access | | IP Multimedia CN Subsystem |
+-------------+ +-------------------------------------+
Figure 2: Overview of the 3GPP IMS architecture
图2:3GPP IMS体系结构概述
The SIP proxies, servers, and registrars shown in Figure 2 are as follows.
图2中所示的SIP代理、服务器和注册器如下所示。
- P-CSCF (Proxy-Call Session Control Function) is the first contact point within the IMS for the subscriber.
- P-CSCF（代理呼叫会话控制功能）是IMS中用户的第一个接触点。
- I-CSCF (Interrogating-CSCF) is the contact point within an operator's network for all connections destined to a subscriber of that network operator, or a roaming subscriber currently located within that network operator's service area.
- I-CSCF（询问CSCF）是运营商网络内所有连接的联络点，目的地为该网络运营商的用户或当前位于该网络运营商服务区内的漫游用户。
- S-CSCF (Serving-CSCF) performs the session control services for the subscriber. It also acts as a SIP Registrar.
- S-CSCF（服务CSCF）为订户执行会话控制服务。它还充当SIP注册器。
IMS capable UEs utilize the GPRS network as an access network for accessing the IMS. Thus, a UE has to have an activated PDP Context to the IMS before it can proceed to use the IMS services. The PDP Context activation is explained briefly in section 3.1.
支持IMS的UE将GPRS网络用作接入IMS的接入网络。因此，UE在能够继续使用IMS服务之前，必须具有IMS的激活PDP上下文。第3.1节简要说明了PDP上下文激活。
The IMS is exclusively IPv6. Thus, the activated PDP Context is of PDP Type IPv6. This means that a 3GPP IP Multimedia terminal uses exclusively IPv6 to access the IMS, and the IMS SIP server and proxy support exclusively IPv6. Hence, all the traffic going to the IMS is IPv6, even if the UE is dual stack capable - this comprises both signaling and user traffic.
IMS专用于IPv6。因此，激活的PDP上下文是PDP类型IPv6。这意味着3GPP IP多媒体终端专门使用IPv6来访问IMS，并且IMS SIP服务器和代理专门支持IPv6。因此，到IMS的所有通信量都是IPv6，即使UE具有双栈能力——这包括信令和用户通信量。
This, of course, does not prevent the usage of other unrelated services (e.g., corporate access) on IPv4.
当然，这并不妨碍在IPv4上使用其他不相关的服务（例如，公司访问）。
This section is divided into two main parts - GPRS scenarios, and scenarios with the IP Multimedia Subsystem (IMS). The first part - GPRS scenarios - concentrates on scenarios with a User Equipment (UE) connecting to services in the Internet, e.g., mail, web. The second part - IMS scenarios - then describes how an IMS capable UE can connect to other SIP-capable nodes in the Internet using the IMS services.
本节分为两个主要部分-GPRS场景和IP多媒体子系统（IMS）场景。第一部分-GPRS场景-集中于用户设备（UE）连接到互联网服务（如邮件、网络）的场景。第二部分-IMS场景-然后描述支持IMS的UE如何使用IMS服务连接到Internet中支持SIP的其他节点。
This section describes the scenarios that might occur when a GPRS UE contacts services, or nodes outside the GPRS network, e.g., web-server in the Internet.
本节描述了GPRS UE联系GPRS网络以外的服务或节点（例如，Internet中的web服务器）时可能发生的情况。
Transition scenarios of the GPRS internal interfaces are outside of the scope of this document.
GPRS内部接口的过渡方案不在本文档范围内。
The following scenarios are described here. In all of the scenarios, the UE is part of a network where there is at least one router of the same IP version, i.e., GGSN, and it is connecting to a node in a different network.
这里描述了以下场景。在所有场景中，UE是网络的一部分，其中存在相同IP版本（即GGSN）的至少一个路由器，并且它连接到不同网络中的节点。
The scenarios here apply also for PDP Context type Point-to-Point Protocol (PPP) where PPP is terminated at the GGSN. On the other hand, where the PPP PDP Context is terminated e.g., at an external ISP, the environment is the same as for general ISP cases.
此处的场景也适用于PDP上下文类型的点对点协议（PPP），其中PPP在GGSN处终止。另一方面，当PPP PDP上下文在外部ISP处终止时，环境与一般ISP情况相同。
1) Dual Stack UE connecting to IPv4 and IPv6 nodes 2) IPv6 UE connecting to an IPv6 node through an IPv4 network 3) IPv4 UE connecting to an IPv4 node through an IPv6 network 4) IPv6 UE connecting to an IPv4 node 5) IPv4 UE connecting to an IPv6 node
1) 连接到IPv4和IPv6节点的双堆栈UE 2）通过IPv4网络连接到IPv6节点的IPv6 UE 3）通过IPv6网络连接到IPv4节点的IPv4 UE 4）连接到IPv4节点的IPv6 UE 5）连接到IPv6节点的IPv4 UE
1) Dual Stack UE connecting to IPv4 and IPv6 nodes
1) 连接到IPv4和IPv6节点的双栈UE
The GPRS system has been designed in a manner that there is the possibility to have simultaneous IPv4, and IPv6 PDP Contexts open. Thus, in cases where the UE is dual stack capable, and in the network there is a GGSN (or separate GGSNs) that supports both connections to IPv4 and IPv6 networks, it is possible to connect to both at the same time. Figure 3 depicts this scenario.
GPRS系统的设计允许同时打开IPv4和IPv6 PDP上下文。因此，在UE具有双栈能力，并且在网络中存在同时支持到IPv4和IPv6网络的连接的GGSN（或单独的GGSN）的情况下，可以同时连接到这两者。图3描述了这个场景。
+-------------+
| |
| UE | +------+
| | | IPv4 |
| | /| |
|------|------+ / +------+
| IPv6 | IPv4 | +--------+ /
+-------------+ IPv4 | | /
| |------------------------| |/
| | |
| IPv6 | GGSN |\
|-------------------------------| | \
+-----------+ | | \ +------+
| GPRS Core | | | \ | IPv6 |
+-----------+ +--------+ \| |
+------+
+-------------+
| |
| UE | +------+
| | | IPv4 |
| | /| |
|------|------+ / +------+
| IPv6 | IPv4 | +--------+ /
+-------------+ IPv4 | | /
| |------------------------| |/
| | |
| IPv6 | GGSN |\
|-------------------------------| | \
+-----------+ | | \ +------+
| GPRS Core | | | \ | IPv6 |
+-----------+ +--------+ \| |
+------+
Figure 3: Dual-Stack Case
图3：双堆栈情况
However, the IPv4 addresses may be a scarce resource for the mobile operator or an ISP. In that case, it might not be possible for the UE to have a globally unique IPv4 address allocated all the time. Hence, the UE could either activate the IPv4 PDP Context only when needed, or be allocated an IPv4 address from a private address space.
然而，对于移动运营商或ISP来说，IPv4地址可能是一种稀缺资源。在这种情况下，UE可能不可能始终分配全局唯一的IPv4地址。因此，UE可以仅在需要时激活IPv4 PDP上下文，或者从专用地址空间分配IPv4地址。
2) IPv6 UE connecting to an IPv6 node through an IPv4 network
2) IPv6 UE通过IPv4网络连接到IPv6节点
Especially in the initial stages of IPv6 deployment, there are cases where an IPv6 node would need to connect to the IPv6 Internet through a network that is IPv4. For instance, this can be seen in current fixed networks, where the access is provided via IPv4 only, but there is an IPv6 network deeper in the Internet. This scenario is shown in Figure 4.
特别是在IPv6部署的初始阶段，有时IPv6节点需要通过IPv4网络连接到IPv6 Internet。例如，这可以在当前的固定网络中看到，在固定网络中，访问仅通过IPv4提供，但在Internet的更深处有一个IPv6网络。此场景如图4所示。
+------+ +------+
| | | | +------+
| UE |------------------| |-----------------| |
| | +-----------+ | GGSN | +---------+ | IPv6 |
| IPv6 | | GPRS Core | | | | IPv4 Net| | |
+------+ +-----------+ +------+ +---------+ +------+
+------+ +------+
| | | | +------+
| UE |------------------| |-----------------| |
| | +-----------+ | GGSN | +---------+ | IPv6 |
| IPv6 | | GPRS Core | | | | IPv4 Net| | |
+------+ +-----------+ +------+ +---------+ +------+
Figure 4: IPv6 nodes communicating over IPv4
图4：通过IPv4进行通信的IPv6节点
In this case, in the GPRS system, the UE would be IPv6 capable, and the GPRS network would provide an IPv6 capable GGSN in the network. However, there is an IPv4 network between the GGSN, and the peer node.
在这种情况下，在GPRS系统中，UE将支持IPv6，并且GPRS网络将在网络中提供支持IPv6的GGSN。但是，GGSN和对等节点之间存在IPv4网络。
3) IPv4 UE connecting to an IPv4 node through an IPv6 network
3) IPv4 UE通过IPv6网络连接到IPv4节点
Further in the future, there are cases where the legacy UEs are still IPv4 only, capable of connecting only to the legacy IPv4 Internet. However, the GPRS operator network has already been upgraded to IPv6. Figure 5 represents this scenario.
进一步在未来，存在遗留ue仍然仅为IPv4的情况，仅能够连接到遗留IPv4因特网。然而，GPRS运营商网络已经升级到IPv6。图5展示了这个场景。
+------+ +------+
| | | | +------+
| UE |------------------| |-----------------| |
| | +-----------+ | GGSN | +---------+ | IPv4 |
| IPv4 | | GPRS Core | | | | IPv6 Net| | |
+------+ +-----------+ +------+ +---------+ +------+
+------+ +------+
| | | | +------+
| UE |------------------| |-----------------| |
| | +-----------+ | GGSN | +---------+ | IPv4 |
| IPv4 | | GPRS Core | | | | IPv6 Net| | |
+------+ +-----------+ +------+ +---------+ +------+
Figure 5: IPv4 nodes communicating over IPv6
图5：通过IPv6进行通信的IPv4节点
In this case, the operator would still provide an IPv4 capable GGSN, and a connection through the IPv6 network to the IPv4 Internet.
在这种情况下，运营商仍将提供支持IPv4的GGSN，以及通过IPv6网络到IPv4互联网的连接。
4) IPv6 UE connecting to an IPv4 node
4) 连接到IPv4节点的IPv6 UE
In this scenario, an IPv6 UE connects to an IPv4 node in the IPv4 Internet. As an example, an IPv6 UE connects to an IPv4 web server in the legacy Internet. In the figure 6, this kind of possible installation is described.
在此场景中，IPv6 UE连接到IPv4 Internet中的IPv4节点。例如，IPv6 UE连接到传统Internet中的IPv4 web服务器。在图6中，描述了这种可能的安装。
+------+ +------+
| | | | +---+ +------+
| UE |------------------| |-----| |----| |
| | +-----------+ | GGSN | | ? | | IPv4 |
| IPv6 | | GPRS Core | | | | | | |
+------+ +-----------+ +------+ +---+ +------+
+------+ +------+
| | | | +---+ +------+
| UE |------------------| |-----| |----| |
| | +-----------+ | GGSN | | ? | | IPv4 |
| IPv6 | | GPRS Core | | | | | | |
+------+ +-----------+ +------+ +---+ +------+
Figure 6: IPv6 node communicating with IPv4 node
图6:IPv6节点与IPv4节点通信
5) IPv4 UE connecting to an IPv6 node
5) 连接到IPv6节点的IPv4 UE
This is similar to the case above, but in the opposite direction. Here an IPv4 UE connects to an IPv6 node in the IPv6 Internet. As an example, a legacy IPv4 UE is connected to an IPv6 server in the IPv6 Internet. Figure 7 depicts this configuration.
这与上述情况类似，但方向相反。此处，IPv4 UE连接到IPv6 Internet中的IPv6节点。例如，传统IPv4 UE连接到IPv6 Internet中的IPv6服务器。图7描述了这种配置。
+------+ +------+
| | | | +---+ +------+
| UE |------------------| |-----| |----| |
| | +-----------+ | GGSN | | ? | | IPv6 |
| IPv4 | | GPRS Core | | | | | | |
+------+ +-----------+ +------+ +---+ +------+
+------+ +------+
| | | | +---+ +------+
| UE |------------------| |-----| |----| |
| | +-----------+ | GGSN | | ? | | IPv6 |
| IPv4 | | GPRS Core | | | | | | |
+------+ +-----------+ +------+ +---+ +------+
Figure 7: IPv4 node communicating with IPv6 node
图7:IPv4节点与IPv6节点通信
As described in section 3.2, IMS is exclusively IPv6. Thus, the number of possible transition scenarios is reduced dramatically. In the following, the possible transition scenarios are listed.
如第3.2节所述，IMS仅为IPv6。因此，可能的过渡场景数量大大减少。下面列出了可能的过渡场景。
1) UE connecting to a node in an IPv4 network through IMS 2) Two IPv6 IMS connected via an IPv4 network
1) UE通过IMS连接到IPv4网络中的节点2）通过IPv4网络连接的两个IPv6 IMS
1) UE connecting to a node in an IPv4 network through IMS
1) UE通过IMS连接到IPv4网络中的节点
This scenario occurs when an IMS UE (IPv6) connects to a node in the IPv4 Internet through the IMS, or vice versa. This happens when the other node is a part of a different system than 3GPP, e.g., a fixed PC, with only IPv4 capabilities. This scenario is shown in the Figure 8.
当IMS UE（IPv6）通过IMS连接到IPv4 Internet中的节点时，就会出现这种情况，反之亦然。当另一个节点是与3GPP不同的系统的一部分（例如，只有IPv4功能的固定PC）时，就会发生这种情况。此场景如图8所示。
+------+ +------+ +-----+
| | | | | | +---+ +------+
| UE |-...-| |-----| IMS |--| |--| |
| | | GGSN | | | | ? | | IPv4 |
| IPv6 | | | | | | | | |
+------+ +------+ +-----+ +---+ +------+
+------+ +------+ +-----+
| | | | | | +---+ +------+
| UE |-...-| |-----| IMS |--| |--| |
| | | GGSN | | | | ? | | IPv4 |
| IPv6 | | | | | | | | |
+------+ +------+ +-----+ +---+ +------+
Figure 8: IMS UE connecting to an IPv4 node
图8：连接到IPv4节点的IMS UE
2) Two IPv6 IMS connected via an IPv4 network
2) 通过IPv4网络连接的两个IPv6 IMS
At the early stages of IMS deployment, there may be cases where two IMS islands are only connected via an IPv4 network such as the legacy Internet. See Figure 9 for illustration.
在IMS部署的早期阶段，可能存在两个IMS孤岛仅通过IPv4网络（如传统互联网）连接的情况。请参见图9以获取说明。
+------+ +------+ +-----+ +-----+
| | | | | | | |
| UE |-...-| |-----| IMS |----------| |
| | | GGSN | | | +------+ | IMS |
| IPv6 | | | | | | IPv4 | | |
+------+ +------+ +-----+ +------+ +-----+
+------+ +------+ +-----+ +-----+
| | | | | | | |
| UE |-...-| |-----| IMS |----------| |
| | | GGSN | | | +------+ | IMS |
| IPv6 | | | | | | IPv4 | | |
+------+ +------+ +-----+ +------+ +-----+
Figure 9: Two IMS islands connected over IPv4
图9：通过IPv4连接的两个IMS孤岛
This document describes possible transition scenarios for 3GPP networks for future study. Solutions and mechanism are explored in other documents. The description of the 3GPP network scenarios does not have any security issues.
本文档描述了3GPP网络的可能过渡场景，以供将来研究。其他文件探讨了解决方案和机制。3GPP网络场景的描述没有任何安全问题。
This document is a result of a joint effort of a design team. The members of the design team are listed in the following.
本文件是设计团队共同努力的结果。下面列出了设计团队的成员。
Alain Durand, Sun Microsystems <Alain.Durand@sun.com>
阿兰·杜兰德，太阳微系统公司<阿兰。Durand@sun.com>
Karim El-Malki, Ericsson Radio Systems <Karim.El-Malki@era.ericsson.se>
卡里姆·马尔基，爱立信无线电系统<Karim.El-Malki@era.ericsson.se>
Niall Richard Murphy, Enigma Consulting Limited <niallm@enigma.ie>
尼尔·理查德·墨菲，英格玛咨询有限公司<niallm@enigma.ie>
Hugh Shieh, AT&T Wireless <hugh.shieh@attws.com>
谢休，AT&T无线<谢休。shieh@attws.com>
Jonne Soininen, Nokia <jonne.soininen@nokia.com>
Jonne Soininen，诺基亚<Jonne。soininen@nokia.com>
Hesham Soliman, Ericsson Radio Systems <hesham.soliman@era.ericsson.se>
赫瑟姆·索利曼，爱立信无线电系统<赫瑟姆。soliman@era.ericsson.se>
Margaret Wasserman, Wind River <mrw@windriver.com>
玛格丽特·沃瑟曼，风之河<mrw@windriver.com>
Juha Wiljakka, Nokia <juha.wiljakka@nokia.com>
诺基亚Juha Wiljakka<Juha。wiljakka@nokia.com>
The authors would like to thank Basavaraj Patil, Tuomo Sipila, Fred Templin, Rod Van Meter, Pekka Savola, Francis Dupont, Christine Fisher, Alain Baudot, Rod Walsh, and Jens Staack for good input, and comments that helped writing this document.
作者要感谢Basavaraj Patil、Tuomo Sipila、Fred Templin、Rod Van Meter、Pekka Savola、Francis Dupont、Christine Fisher、Alain Baudot、Rod Walsh和Jens Staack的良好投入和评论，这些都有助于编写本文件。
[1] 3GPP TS 23.060 v 5.2.0, "General Packet Radio Service (GPRS); Service description; Stage 2(Release 5)", June 2002.
[1] 3GPP TS 23.060 v 5.2.0，“通用分组无线业务（GPRS）；业务描述；第2阶段（第5版）”，2002年6月。
[2] 3GPP TS 23.228 v 5.3.0, " IP Multimedia Subsystem (IMS); Stage 2(Release 5)", January 2002.
[2] 3GPP TS 23.228 v 5.3.0，“IP多媒体子系统（IMS）；第2阶段（第5版）”，2002年1月。
[3] 3GPP TS 24.228 V5.0.0, "Signalling flows for the IP multimedia call control based on SIP and SDP; Stage 3 (Release 5)", March 2002.
[3] 3GPP TS 24.228 V5.0.0，“基于SIP和SDP的IP多媒体呼叫控制信令流；第3阶段（版本5）”，2002年3月。
[4] 3GPP TS 24.229 V5.0.0, "IP Multimedia Call Control Protocol based on SIP and SDP; Stage 3 (Release 5)", March 2002.
[4] 3GPP TS 24.229 V5.0.0，“基于SIP和SDP的IP多媒体呼叫控制协议；第3阶段（版本5）”，2002年3月。
[5] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, June 2002.
[5] Rosenberg，J.，Schulzrinne，H.，Camarillo，G.，Johnston，A.，Peterson，J.，Sparks，R.，Handley，M.和E.Schooler，“SIP：会话启动协议”，RFC 3261，2002年6月。
[6] Wasserman, M., "Recommendations for IPv6 in Third Generation Partnership Project (3GPP) Standards", RFC 3314, September 2002.
[6] Wasserman，M.，“第三代合作伙伴项目（3GPP）标准中IPv6的建议”，RFC 3314，2002年9月。
Jonne Soininen Nokia 313 Fairchild Dr. Mountain View, CA, USA
Jonne Soininen诺基亚313飞兆儿童美国加利福尼亚州山景城博士
Phone: +1-650-864-6794
EMail: jonne.soininen@nokia.com
Phone: +1-650-864-6794
EMail: jonne.soininen@nokia.com
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Acknowledgement
确认
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