draft-ietf-v6ops-3gpp-cases-03.txt   rfc3574.txt 
Internet Draft J. Soininen (ed.) Network Working Group J. Soininen, Ed.
Document: draft-ietf-v6ops-3gpp-cases-03.txt Nokia Request for Comments: 3574 Nokia
Expires: September 2003 March 2003 Category: Informational August 2003
Transition Scenarios for 3GPP Networks Transition Scenarios for 3GPP Networks
Status of this Memo Status of this Memo
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Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved. Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract Abstract
This document describes different scenarios in Third Generation This document describes different scenarios in Third Generation
Partnership Project (3GPP) defined packet network, i.e. General Partnership Project (3GPP) defined packet network, i.e., General
Packet Radio Service (GPRS) that would need IP version 6 and IP Packet Radio Service (GPRS) that would need IP version 6 and IP
version 4 transition. The focus of this document is on the scenarios version 4 transition. The focus of this document is on the scenarios
where the User Equipment (UE) connects to nodes in other networks, where the User Equipment (UE) connects to nodes in other networks,
e.g. in the Internet. GPRS network internal transition scenarios, e.g., in the Internet. GPRS network internal transition scenarios,
i.e. between different GPRS elements in the network, are out of i.e., between different GPRS elements in the network, are out of
scope. scope. The purpose of the document is to list the scenarios for
further discussion and study.
The purpose of the document is to list the scenarios for further
discussion and study.
Table of Contents Table of Contents
1. Introduction...................................................2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Scope of the Document..........................................2 2. Scope of the Document. . . . . . . . . . . . . . . . . . . . . 2
3. Brief Description of the 3GPP Network Environment..............3 3. Brief Description of the 3GPP Network Environment. . . . . . . 2
3.1 GPRS Architecture Basics...................................3 3.1 GPRS Architecture Basics . . . . . . . . . . . . . . . . . 3
3.2 IP Multimedia Core Network Subsystem (IMS).................4 3.2 IP Multimedia Core Network Subsystem (IMS) . . . . . . . . 3
4. Transition Scenarios...........................................5 4. Transition Scenarios . . . . . . . . . . . . . . . . . . . . . 5
4.1 GPRS Scenarios.............................................5 4.1 GPRS Scenarios . . . . . . . . . . . . . . . . . . . . . . 5
4.2 IMS Scenarios..............................................8 4.2 IMS Scenarios . . . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations........................................9 5. Security Considerations. . . . . . . . . . . . . . . . . . . . 9
Authors..........................................................10 6. Contributing Authors . . . . . . . . . . . . . . . . . . . . . 10
Normative References.............................................11 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
Informative references...........................................11 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Editor's Address.................................................11 8.1. Normative References . . . . . . . . . . . . . . . . . . 10
8.2. Informative References . . . . . . . . . . . . . . . . . 11
Copyright 9. Editor's Address . . . . . . . . . . . . . . . . . . . . . . . 11
10. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 12
(C) The Internet Society (2003). All Rights Reserved.
1. Introduction 1. Introduction
This document describes the transition scenarios in 3GPP packet data This document describes the transition scenarios in 3GPP packet data
networks that might come up in the deployment phase of IPv6. The networks that might come up in the deployment phase of IPv6. The
main purpose of this document is to identify and to document those main purpose of this document is to identify and to document those
scenarios for further discussion and study them in the v6ops working scenarios for further discussion and study them in the v6ops working
group. group.
Just a brief overview of the 3GPP packet data network, GPRS, is given Just a brief overview of the 3GPP packet data network, GPRS, is given
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2. Scope of the Document 2. Scope of the Document
The scope is to describe the possible transition scenarios in the The scope is to describe the possible transition scenarios in the
3GPP defined GPRS network where a UE connects to, or is contacted 3GPP defined GPRS network where a UE connects to, or is contacted
from, the Internet or another UE. The document describes scenarios from, the Internet or another UE. The document describes scenarios
with and without the usage of the SIP-based (Session Initiation with and without the usage of the SIP-based (Session Initiation
Protocol [5]) IP Multimedia Core Network Subsystem (IMS). The 3GPP Protocol [5]) IP Multimedia Core Network Subsystem (IMS). The 3GPP
releases 1999, 4, and 5 are considered as the basis. releases 1999, 4, and 5 are considered as the basis.
Out of scope are scenarios inside the GPRS network, i.e. on the Out of scope are scenarios inside the GPRS network, i.e., on the
different interfaces of the GPRS network. This document neither different interfaces of the GPRS network. This document neither
changes 3GPP specifications, nor proposes changes to the current changes 3GPP specifications, nor proposes changes to the current
specifications. specifications.
In addition, the possible transition scenarios are described. The In addition, the possible transition scenarios are described. The
solutions will be documented in a separate document. solutions will be documented in a separate document.
All the possible scenarios are listed here. Further analysis may show All the possible scenarios are listed here. Further analysis may
that some of the scenarios are not actually relevant in this context. show that some of the scenarios are not actually relevant in this
context.
3. Brief Description of the 3GPP Network Environment 3. Brief Description of the 3GPP Network Environment
This section describes the most important concepts of the 3GPP This section describes the most important concepts of the 3GPP
environment for understanding the transition scenarios. The first environment for understanding the transition scenarios. The first
part of the description gives a brief overview to the GPRS network as part of the description gives a brief overview to the GPRS network as
such. The second part concentrates on the IP Multimedia Core Network such. The second part concentrates on the IP Multimedia Core Network
Subsystem (IMS). Subsystem (IMS).
3.1 GPRS Architecture Basics 3.1. GPRS Architecture Basics
This section gives an overview to the most important concepts of the This section gives an overview to the most important concepts of the
3GPP packet architecture. For more detailed description, please see 3GPP packet architecture. For more detailed description, please see
[1]. [1].
From the point of view of this document, the most relevant 3GPP From the point of view of this document, the most relevant 3GPP
architectural elements are the User Equipment (UE), and the Gateway architectural elements are the User Equipment (UE), and the Gateway
GPRS Support Node (GGSN). A simplified picture of the architecture is GPRS Support Node (GGSN). A simplified picture of the architecture
shown in Figure 1. is shown in Figure 1.
The UE is the mobile phone. It can either be an integrated device 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 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. separate GPRS device, and separate equipment with the IP stack, e.g.,
a laptop. a laptop.
The GGSN serves as an anchor-point for the GPRS mobility management. The GGSN serves as an anchor-point for the GPRS mobility management.
It also serves as the default router for the UE. It also serves as the default router for the UE.
The Peer node mentioned in the picture refers to a node with which The Peer node mentioned in the picture refers to a node with which
the UE is communicating. the UE is communicating.
-- ---- ************ --------- -- ---- ************ ---------
|UE|- ... -|GGSN|--+--* IPv4/v6 NW *--+--|Peer node| |UE|- ... -|GGSN|--+--* IPv4/v6 NW *--+--|Peer node|
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The GGSN serves as an anchor-point for the GPRS mobility management. The GGSN serves as an anchor-point for the GPRS mobility management.
It also serves as the default router for the UE. It also serves as the default router for the UE.
The Peer node mentioned in the picture refers to a node with which The Peer node mentioned in the picture refers to a node with which
the UE is communicating. the UE is communicating.
-- ---- ************ --------- -- ---- ************ ---------
|UE|- ... -|GGSN|--+--* IPv4/v6 NW *--+--|Peer node| |UE|- ... -|GGSN|--+--* IPv4/v6 NW *--+--|Peer node|
-- ---- ************ --------- -- ---- ************ ---------
Figure 1: Simplified GPRS Architecture Figure 1: Simplified GPRS Architecture
There is a dedicated link between the UE and the GGSN called the There is a dedicated link between the UE and the GGSN called the
Packet Data Protocol (PDP) Context. This link is created through the Packet Data Protocol (PDP) Context. This link is created through the
PDP Context activation process. During the activation the UE is PDP Context activation process. During the activation the UE is
configured with its IP address and other information needed to configured with its IP address and other information needed to
maintain IP access, e.g. DNS server address. There are three maintain IP access, e.g., DNS server address. There are three
different types of PDP Contexts: IPv4, IPv6, and Point-to-Point different types of PDP Contexts: IPv4, IPv6, and Point-to-Point
Protocol (PPP). Protocol (PPP).
A UE can have one or more simultaneous PDP Contexts open to the same 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 or to different GGSNs. The PDP Context can be either of the same or
different types. different types.
3.2 IP Multimedia Core Network Subsystem (IMS) 3.2. IP Multimedia Core Network Subsystem (IMS)
IP Multimedia Core Network Subsystem (IMS) is an architecture for IP Multimedia Core Network Subsystem (IMS) is an architecture for
supporting multimedia services via a SIP infrastructure. It is supporting multimedia services via a SIP infrastructure. It is
specified in 3GPP Release 5. This section provides an overview of the specified in 3GPP Release 5. This section provides an overview of
3GPP IMS and is not intended to be comprehensive. A more detailed the 3GPP IMS and is not intended to be comprehensive. A more
description can be found in [2], [3] and [4]. detailed description can be found in [2], [3] and [4].
The IMS comprises a set of SIP proxies, servers, and registrars. In The IMS comprises a set of SIP proxies, servers, and registrars. In
addition, there are Media Gateways (MGWs) that offer connections to addition, there are Media Gateways (MGWs) that offer connections to
non-IP networks such as the Public Switched Telephony Network (PSTN). non-IP networks such as the Public Switched Telephony Network (PSTN).
A simplified overview of the IMS is depicted in figure 2. A simplified overview of the IMS is depicted in figure 2.
+-------------+ +-------------------------------------+ +-------------+ +-------------------------------------+
| | | +------+ | | | | +------+ |
| | | |S-CSCF|--- | | | |S-CSCF|---
| | | | +------+ | | | | | +------+ |
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- I-CSCF (Interrogating-CSCF) is the contact point within an - I-CSCF (Interrogating-CSCF) is the contact point within an
operator's network for all connections destined to a subscriber operator's network for all connections destined to a subscriber
of that network operator, or a roaming subscriber currently of that network operator, or a roaming subscriber currently
located within that network operator's service area. located within that network operator's service area.
- S-CSCF (Serving-CSCF) performs the session control services for - S-CSCF (Serving-CSCF) performs the session control services for
the subscriber. It also acts as a SIP Registrar. the subscriber. It also acts as a SIP Registrar.
IMS capable UEs utilize the GPRS network as an access network for 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 accessing the IMS. Thus, a UE has to have an activated PDP Context
the IMS before it can proceed to use the IMS services. The PDP to the IMS before it can proceed to use the IMS services. The PDP
Context activation is explained briefly in section 3.1. Context activation is explained briefly in section 3.1.
The IMS is exclusively IPv6. Thus, the activated PDP Context is of The IMS is exclusively IPv6. Thus, the activated PDP Context is of
PDP Type IPv6. This means that a 3GPP IP Multimedia terminal uses 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 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 support exclusively IPv6. Hence, all the traffic going to the IMS is
IPv6, even if the UE is dual stack capable - this comprises both IPv6, even if the UE is dual stack capable - this comprises both
signaling and user traffic. signaling and user traffic.
This, of course, does not prevent the usage of other unrelated This, of course, does not prevent the usage of other unrelated
services (e.g. corporate access) on IPv4. services (e.g., corporate access) on IPv4.
4. Transition Scenarios 4. Transition Scenarios
This section is divided into two main parts - GPRS scenarios, and This section is divided into two main parts - GPRS scenarios, and
scenarios with the IP Multimedia Subsystem (IMS). The first part - scenarios with the IP Multimedia Subsystem (IMS). The first part -
GPRS scenarios - concentrates on scenarios with a User Equipment (UE) GPRS scenarios - concentrates on scenarios with a User Equipment (UE)
connecting to services in the Internet, e.g. mail, web. The second connecting to services in the Internet, e.g., mail, web. The second
part - IMS scenarios - then describes how an IMS capable UE can part - IMS scenarios - then describes how an IMS capable UE can
connect to other SIP-capable nodes in the Internet using the IMS connect to other SIP-capable nodes in the Internet using the IMS
services. services.
4.1 GPRS Scenarios 4.1. GPRS Scenarios
This section describes the scenarios that might occur when a GPRS UE This section describes the scenarios that might occur when a GPRS UE
contacts services, or nodes outside the GPRS network, e.g. web-server contacts services, or nodes outside the GPRS network, e.g., web-
in the Internet. server in the Internet.
Transition scenarios of the GPRS internal interfaces are outside of Transition scenarios of the GPRS internal interfaces are outside of
the scope of this document. the scope of this document.
The following scenarios are described here. In all of the scenarios, 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 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 same IP version, i.e., GGSN, and it is connecting to a node in a
different network. different network.
The scenarios here apply also for PDP Context type Point-to-Point The scenarios here apply also for PDP Context type Point-to-Point
Protocol (PPP) where PPP is terminated at the GGSN. On the other 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 hand, where the PPP PDP Context is terminated e.g., at an external
ISP, the environment is the same as for general ISP cases. ISP, the environment is the same as for general ISP cases.
1) Dual Stack UE connecting to IPv4 and IPv6 nodes 1) Dual Stack UE connecting to IPv4 and IPv6 nodes
2) IPv6 UE connecting to an IPv6 node through an IPv4 network 2) IPv6 UE connecting to an IPv6 node through an IPv4 network
3) IPv4 UE connecting to an IPv4 node through an IPv6 network 3) IPv4 UE connecting to an IPv4 node through an IPv6 network
4) IPv6 UE connecting to an IPv4 node 4) IPv6 UE connecting to an IPv4 node
5) IPv4 UE connecting to an IPv6 node 5) IPv4 UE connecting to an IPv6 node
1) Dual Stack UE connecting to IPv4 and IPv6 nodes 1) Dual Stack UE connecting to IPv4 and IPv6 nodes
The GPRS system has been designed in a manner that there is the The GPRS system has been designed in a manner that there is the
possibility to have simultaneous IPv4, and IPv6 PDP Contexts open. possibility to have simultaneous IPv4, and IPv6 PDP Contexts open.
Thus, in cases where the UE is dual stack capable, and in the network Thus, in cases where the UE is dual stack capable, and in the
there is a GGSN (or separate GGSNs) that supports both connections to network there is a GGSN (or separate GGSNs) that supports both
IPv4 and IPv6 networks, it is possible to connect to both at the same connections to IPv4 and IPv6 networks, it is possible to connect
time. Figure 3 depicts this scenario. to both at the same time. Figure 3 depicts this scenario.
+-------------+ +-------------+
| | | |
| UE | +------+ | UE | +------+
| | | IPv4 | | | | IPv4 |
| | /| | | | /| |
|------|------+ / +------+ |------|------+ / +------+
| IPv6 | IPv4 | +--------+ / | IPv6 | IPv4 | +--------+ /
+-------------+ IPv4 | | / +-------------+ IPv4 | | /
| |------------------------| |/ | |------------------------| |/
| | | | | |
| IPv6 | GGSN |\ | IPv6 | GGSN |\
|-------------------------------| | \ |-------------------------------| | \
+-----------+ | | \ +------+ +-----------+ | | \ +------+
| GPRS Core | | | \ | IPv6 | | GPRS Core | | | \ | IPv6 |
+-----------+ +--------+ | | +-----------+ +--------+ \| |
+------+ +------+
Figure 3: Dual-Stack Case Figure 3: Dual-Stack Case
However, the IPv4 addresses may be a scarce resource for the mobile However, the IPv4 addresses may be a scarce resource for the
operator or an ISP. In that case, it might not be possible for the UE mobile operator or an ISP. In that case, it might not be possible
to have a globally unique IPv4 address allocated all the time. Hence, for the UE to have a globally unique IPv4 address allocated all
the UE could either activate the IPv4 PDP Context only when needed, the time. Hence, the UE could either activate the IPv4 PDP
or be allocated an IPv4 address from a private address space. Context only when needed, or be allocated an IPv4 address from a
private address space.
2) IPv6 UE connecting to an IPv6 node through an IPv4 network 2) IPv6 UE connecting to an IPv6 node through an IPv4 network
Especially in the initial stages of IPv6 deployment, there are cases Especially in the initial stages of IPv6 deployment, there are
where an IPv6 node would need to connect to the IPv6 Internet through cases where an IPv6 node would need to connect to the IPv6
a network that is IPv4. For instance, this can be seen in current Internet through a network that is IPv4. For instance, this can
fixed networks, where the access is provided via IPv4 only, but there be seen in current fixed networks, where the access is provided
is an IPv6 network deeper in the Internet. This scenario is shown in via IPv4 only, but there is an IPv6 network deeper in the
Figure 4. Internet. This scenario is shown in Figure 4.
+------+ +------+ +------+ +------+
| | | | +------+ | | | | +------+
| UE |------------------| |-----------------| | | UE |------------------| |-----------------| |
| | +-----------+ | GGSN | +---------+ | IPv6 | | | +-----------+ | GGSN | +---------+ | IPv6 |
| IPv6 | | GPRS Core | | | | IPv4 Net| | | | IPv6 | | GPRS Core | | | | IPv4 Net| | |
+------+ +-----------+ +------+ +---------+ +------+ +------+ +-----------+ +------+ +---------+ +------+
Figure 4: IPv6 nodes communicating over IPv4 Figure 4: IPv6 nodes communicating over IPv4
In this case, in the GPRS system, the UE would be IPv6 capable, and In this case, in the GPRS system, the UE would be IPv6 capable,
the GPRS network would provide an IPv6 capable GGSN in the network. and the GPRS network would provide an IPv6 capable GGSN in the
However, there is an IPv4 network between the GGSN, and the peer network. However, there is an IPv4 network between the GGSN, and
node. the peer node.
3) IPv4 UE connecting to an IPv4 node through an IPv6 network 3) IPv4 UE connecting to an IPv4 node through an IPv6 network
Further in the future, there are cases where the legacy UEs are still Further in the future, there are cases where the legacy UEs are
IPv4 only, capable of connecting only to the legacy IPv4 Internet. still IPv4 only, capable of connecting only to the legacy IPv4
However, the GPRS operator network has already been upgraded to IPv6. Internet. However, the GPRS operator network has already been
Figure 5 represents this scenario. upgraded to IPv6. Figure 5 represents this scenario.
+------+ +------+ +------+ +------+
| | | | +------+ | | | | +------+
| UE |------------------| |-----------------| | | UE |------------------| |-----------------| |
| | +-----------+ | GGSN | +---------+ | IPv4 | | | +-----------+ | GGSN | +---------+ | IPv4 |
| IPv4 | | GPRS Core | | | | IPv6 Net| | | | IPv4 | | GPRS Core | | | | IPv6 Net| | |
+------+ +-----------+ +------+ +---------+ +------+ +------+ +-----------+ +------+ +---------+ +------+
Figure 5: IPv4 nodes communicating over IPv6 Figure 5: IPv4 nodes communicating over IPv6
In this case, the operator would still provide an IPv4 capable GGSN, In this case, the operator would still provide an IPv4 capable
and a connection through the IPv6 network to the IPv4 Internet. GGSN, and a connection through the IPv6 network to the IPv4
Internet.
4) IPv6 UE connecting to an IPv4 node 4) IPv6 UE connecting to an IPv4 node
In this scenario, an IPv6 UE connects to an IPv4 node in the IPv4 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 Internet. As an example, an IPv6 UE connects to an IPv4 web
the legacy Internet. In the figure 6, this kind of possible server in the legacy Internet. In the figure 6, this kind of
installation is described. possible installation is described.
+------+ +------+ +------+ +------+
| | | | +---+ +------+ | | | | +---+ +------+
| UE |------------------| |-----| |----| | | UE |------------------| |-----| |----| |
| | +-----------+ | GGSN | | ? | | IPv4 | | | +-----------+ | GGSN | | ? | | IPv4 |
| IPv6 | | GPRS Core | | | | | | | | IPv6 | | GPRS Core | | | | | | |
+------+ +-----------+ +------+ +---+ +------+ +------+ +-----------+ +------+ +---+ +------+
Figure 6: IPv6 node communicating with IPv4 node Figure 6: IPv6 node communicating with IPv4 node
5) IPv4 UE connecting to an IPv6 node 5) IPv4 UE connecting to an IPv6 node
This is similar to the case above, but in the opposite direction. 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 Here an IPv4 UE connects to an IPv6 node in the IPv6 Internet. As
example, a legacy IPv4 UE is connected to an IPv6 server in the IPv6 an example, a legacy IPv4 UE is connected to an IPv6 server in the
Internet. Figure 7 depicts this configuration. IPv6 Internet. Figure 7 depicts this configuration.
+------+ +------+ +------+ +------+
| | | | +---+ +------+ | | | | +---+ +------+
| UE |------------------| |-----| |----| | | UE |------------------| |-----| |----| |
| | +-----------+ | GGSN | | ? | | IPv6 | | | +-----------+ | GGSN | | ? | | IPv6 |
| IPv4 | | GPRS Core | | | | | | | | IPv4 | | GPRS Core | | | | | | |
+------+ +-----------+ +------+ +---+ +------+ +------+ +-----------+ +------+ +---+ +------+
Figure 7: IPv4 node communicating with IPv6 node Figure 7: IPv4 node communicating with IPv6 node
4.2 IMS Scenarios 4.2. IMS Scenarios
As described in section 3.2, IMS is exclusively IPv6. Thus, the As described in section 3.2, IMS is exclusively IPv6. Thus, the
number of possible transition scenarios is reduced dramatically. In number of possible transition scenarios is reduced dramatically. In
the following, the possible transition scenarios are listed. the following, the possible transition scenarios are listed.
1) UE connecting to a node in an IPv4 network through IMS 1) UE connecting to a node in an IPv4 network through IMS
2) Two IPv6 IMS connected via an IPv4 network 2) Two IPv6 IMS connected via an IPv4 network
1) UE connecting to a node in an IPv4 network through IMS 1) UE connecting to a node in an IPv4 network through IMS
This scenario occurs when an IMS UE (IPv6) connects to a node in the This scenario occurs when an IMS UE (IPv6) connects to a node in
IPv4 Internet through the IMS, or vice versa. This happens when the the IPv4 Internet through the IMS, or vice versa. This happens
other node is a part of a different system than 3GPP, e.g. a fixed when the other node is a part of a different system than 3GPP,
PC, with only IPv4 capabilities. This scenario is shown in the Figure e.g., a fixed PC, with only IPv4 capabilities. This scenario is
8. shown in the Figure 8.
+------+ +------+ +-----+ +------+ +------+ +-----+
| | | | | | +---+ +------+ | | | | | | +---+ +------+
| UE |-...-| |-----| IMS |--| |--| | | UE |-...-| |-----| IMS |--| |--| |
| | | GGSN | | | | ? | | IPv4 | | | | GGSN | | | | ? | | IPv4 |
| IPv6 | | | | | | | | | | IPv6 | | | | | | | | |
+------+ +------+ +-----+ +---+ +------+ +------+ +------+ +-----+ +---+ +------+
Figure 8: IMS UE connecting to an IPv4 node Figure 8: IMS UE connecting to an IPv4 node
2) Two IPv6 IMS connected via an IPv4 network 2) Two IPv6 IMS connected via an IPv4 network
At the early stages of IMS deployment, there may be cases where two At the early stages of IMS deployment, there may be cases where
IMS islands are only connected via an IPv4 network such as the legacy two IMS islands are only connected via an IPv4 network such as the
Internet. See Figure 9 for illustration. legacy Internet. See Figure 9 for illustration.
+------+ +------+ +-----+ +-----+ +------+ +------+ +-----+ +-----+
| | | | | | | | | | | | | | | |
| UE |-...-| |-----| IMS |----------| | | UE |-...-| |-----| IMS |----------| |
| | | GGSN | | | +------+ | IMS | | | | GGSN | | | +------+ | IMS |
| IPv6 | | | | | | IPv4 | | | | IPv6 | | | | | | IPv4 | | |
+------+ +------+ +-----+ +------+ +-----+ +------+ +------+ +-----+ +------+ +-----+
Figure 9: Two IMS islands connected over IPv4 Figure 9: Two IMS islands connected over IPv4
5. Security Considerations 5. Security Considerations
This document describes possible transition scenarios for 3GPP This document describes possible transition scenarios for 3GPP
networks for future study. Solutions and mechanism are explored in networks for future study. Solutions and mechanism are explored in
other documents: The description of the 3GPP network scenarios does other documents. The description of the 3GPP network scenarios does
not have any security considerations. not have any security issues.
Authors 6. Contributing Authors
This document is a result of a joint effort of a design team. The This document is a result of a joint effort of a design team. The
members of the design team are listed in the following. members of the design team are listed in the following.
Alain Durand, Sun Microsystems Alain Durand, Sun Microsystems
<Alain.Durand@sun.com> <Alain.Durand@sun.com>
Karim El-Malki, Ericsson Radio Systems Karim El-Malki, Ericsson Radio Systems
<Karim.El-Malki@era.ericsson.se> <Karim.El-Malki@era.ericsson.se>
skipping to change at page 10, line 34 skipping to change at page 10, line 34
Hesham Soliman, Ericsson Radio Systems Hesham Soliman, Ericsson Radio Systems
<hesham.soliman@era.ericsson.se> <hesham.soliman@era.ericsson.se>
Margaret Wasserman, Wind River Margaret Wasserman, Wind River
<mrw@windriver.com> <mrw@windriver.com>
Juha Wiljakka, Nokia Juha Wiljakka, Nokia
<juha.wiljakka@nokia.com> <juha.wiljakka@nokia.com>
Acknowledgements 7. Acknowledgements
The authors would like to thank Basavaraj Patil, Tuomo Sipila, Fred The authors would like to thank Basavaraj Patil, Tuomo Sipila, Fred
Templin, Rod Van Meter, Pekka Savola, Francis Dupont, Christine Templin, Rod Van Meter, Pekka Savola, Francis Dupont, Christine
Fisher, Alain Baudot, Rod Walsh, and Jens Staack for good input, and Fisher, Alain Baudot, Rod Walsh, and Jens Staack for good input, and
comments that helped writing this document. comments that helped writing this document.
Normative References 8. References
8.1. Normative References
[1] 3GPP TS 23.060 v 5.2.0, "General Packet Radio Service (GPRS); [1] 3GPP TS 23.060 v 5.2.0, "General Packet Radio Service (GPRS);
Service description; Stage 2(Release 5)", June 2002. Service description; Stage 2(Release 5)", June 2002.
[2] 3GPP TS 23.228 v 5.3.0, " IP Multimedia Subsystem (IMS); Stage [2] 3GPP TS 23.228 v 5.3.0, " IP Multimedia Subsystem (IMS); Stage
2(Release 5)", January 2002. 2(Release 5)", January 2002.
[3] 3GPP TS 24.228 V5.0.0, "Signalling flows for the IP multimedia [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 call control based on SIP and SDP; Stage 3 (Release 5)", March
2002. 2002.
[4] 3GPP TS 24.229 V5.0.0, "IP Multimedia Call Control Protocol [4] 3GPP TS 24.229 V5.0.0, "IP Multimedia Call Control Protocol based
based on SIP and SDP; Stage 3 (Release 5)", March 2002. on SIP and SDP; Stage 3 (Release 5)", March 2002.
[5] Rosenberg J., Schulzrinne H., Camarillo G., Johnston A., [5] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
Peterson J., Sparks R., Handley M., Schooler E., " SIP: Session Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP:
Initiation Protocol", RFC3261, June 2002. Session Initiation Protocol", RFC 3261, June 2002.
Informative references 8.2. Informative References
[6] Wasserman, M., "Recommendations for IPv6 in Third Generation [6] Wasserman, M., "Recommendations for IPv6 in Third Generation
Partnership Project (3GPP) Standards", RFC3314, September 2002. Partnership Project (3GPP) Standards", RFC3314, September 2002.
Editor's Address 9. Editor's Address
Jonne Soininen Jonne Soininen
Nokia Nokia
313 Fairchild Dr. Phone: +1-650-864-6794 313 Fairchild Dr.
Mountain View, CA, USA Email: jonne.soininen@nokia.com Mountain View, CA, USA
Phone: +1-650-864-6794
EMail: jonne.soininen@nokia.com
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