draft-ietf-v6ops-3gpp-cases-02.txt		draft-ietf-v6ops-3gpp-cases-03.txt
	Internet Draft J. Soininen,		Internet Draft J. Soininen (ed.)
	Document: draft-ietf-v6ops-3gpp-cases-02.txt Editor		Document: draft-ietf-v6ops-3gpp-cases-03.txt Nokia
	Expires: July 2003 Nokia		Expires: September 2003 March 2003
	January 2003
	Transition Scenarios for 3GPP Networks		Transition Scenarios for 3GPP Networks
	Status of this Memo		Status of this Memo
	This document is an Internet-Draft and is in full conformance with		This document is an Internet-Draft and is in full conformance with
	all provisions of Section 10 of RFC2026.		all provisions of Section 10 of RFC2026.
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF), its areas, and its working groups. Note that		Task Force (IETF), its areas, and its working groups. Note that
	skipping to change at page 1, line 32		skipping to change at page 1, line 31
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	The list of current Internet-Drafts can be accessed at		The list of current Internet-Drafts can be accessed at
	http://www.ietf.org/ietf/1id-abstracts.txt		http://www.ietf.org/ietf/1id-abstracts.txt
	The list of Internet-Draft Shadow Directories can be accessed at		The list of Internet-Draft Shadow Directories can be accessed at
	http://www.ietf.org/shadow.html.		http://www.ietf.org/shadow.html.
	Copyright Notice		Copyright Notice
	Copyright (C) The Internet Society (2002). 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 scope		i.e. between different GPRS elements in the network, are out of
	of this document.		scope.
	The purpose of the document is to list the scenarios for further		The purpose of the document is to list the scenarios for further
	discussion and study.		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..............3
	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).................4
	4. Transition scenarios...........................................5		4. Transition Scenarios...........................................5
	4.1 GPRS Scenarios.............................................5		4.1 GPRS Scenarios.............................................5
	4.2 Transition scenarios with IMS..............................8		4.2 IMS Scenarios..............................................8
	5. Security Considerations........................................9		5. Security Considerations........................................9
	Authors...........................................................9		Authors..........................................................10
	Informative references...........................................10		Normative References.............................................11
	Normative References.............................................10		Informative references...........................................11
	Editor's Address.................................................10		Editor's Address.................................................11
	Copyright		Copyright
	(C) The Internet Society (2002). All Rights Reserved.		(C) The Internet Society (2003). All Rights Reserved.
	1. Introduction		1. Introduction
	This document will describe the transition scenarios in 3GPP packet		This document describes the transition scenarios in 3GPP packet data
	data networks that might come up in the deployment phase of IPv6.		networks that might come up in the deployment phase of IPv6. The
	The main purpose of this document is to identify, and document those		main purpose of this document is to identify and to document those
	scenarios for further discussion, and for study in the v6ops working		scenarios for further discussion and study them in the v6ops working
	group.		group.
	This document gives neither an overview, nor an explanation of 3GPP		Just a brief overview of the 3GPP packet data network, GPRS, is given
	or the 3GPP packet data network, GPRS. A good overview of the 3GPP		to help the reader to better understand the transition scenarios. A
	specified GPRS can be found from [1]. The GPRS architecture		better overview of the 3GPP specified GPRS can be found for example
	specification is defined in [2].		from [6]. The GPRS architecture is defined in [1].
	2. Scope of the document		2. Scope of the Document
	The scope of this document is to describe the possible transition		The scope is to describe the possible transition scenarios in the
	scenarios in the 3GPP defined GPRS network where a UE connects to, or		3GPP defined GPRS network where a UE connects to, or is contacted
	is contacted from, the Internet or another UE. The document describes		from, the Internet or another UE. The document describes scenarios
	scenarios with and without the usage of the SIP based IP Multimedia		with and without the usage of the SIP-based (Session Initiation
	Core Network Subsystem (IMS).		Protocol [5]) IP Multimedia Core Network Subsystem (IMS). The 3GPP
			releases 1999, 4, and 5 are considered as the basis.
	The scope of this document does not include scenarios inside the GPRS		Out of scope are scenarios inside the GPRS network, i.e. on the
	network, i.e. on the different interfaces of the GPRS network. This		different interfaces of the GPRS network. This document neither
	document neither changes 3GPP specifications, nor proposes changes to		changes 3GPP specifications, nor proposes changes to the current
	the current specifications.		specifications.
	In addition, this document describes the possible transition		In addition, the possible transition scenarios are described. The
	scenarios. The solutions will be documented in a separate document.		solutions will be documented in a separate document.
	These scenarios may or may not be found feasible, or even likely in		All the possible scenarios are listed here. Further analysis may show
	further study.		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
	[2].		[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 is
	shown in Figure 1.		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
	comprised of 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 a separate equipment with the IP stack,		separate GPRS device, and separate equipment with the IP stack, e.g.
	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|
	-- ---- ************ ---------		-- ---- ************ ---------
	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 a SIP based multimedia		IP Multimedia Core Network Subsystem (IMS) is an architecture for
	service architecture. It is specified in Release 5 of 3GPP. This		supporting multimedia services via a SIP infrastructure. It is
	section provides an overview of the 3GPP IMS and is not intended to		specified in 3GPP Release 5. This section provides an overview of the
	be comprehensive. A more detailed description can be found in [3],		3GPP IMS and is not intended to be comprehensive. A more detailed
	[4] and [5].		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|---
	| | | | +------+ |		| | | | +------+ |
	+-|+ | | | / |		+-|+ | | | / |
	| | | SIP Sig. | | +------+ +------+ |		| | | SIP Sig. | | +------+ +------+ |
	| |----|------+------|--|----|P-CSCF|----------|I-CSCF| |		| |----|------+------|--|----|P-CSCF|----------|I-CSCF| |
	| | | | | +------+ +------+ |		| | | | | +------+ +------+ |
	| |-----------+------------------------------------------------		| |-----------+------------------------------------------------
	+--+ | User traf. | | |		+--+ | User traf. | | |
	skipping to change at page 4, line 43		skipping to change at page 4, line 44
	+-------------+ +-------------------------------------+		+-------------+ +-------------------------------------+
	Figure 2: Overview of the 3GPP IMS architecture		Figure 2: Overview of the 3GPP IMS architecture
	The SIP proxies, servers, and registrars shown in Figure 2 are as		The SIP proxies, servers, and registrars shown in Figure 2 are as
	follows.		follows.
	- P-CSCF (Proxy-Call Session Control Function) is the first		- P-CSCF (Proxy-Call Session Control Function) is the first
	contact point within the IMS for the subscriber.		contact point within the IMS for the subscriber.
	- I-CSCF (Interrogating-CSCF) is the contact point within an		- I-CSCF (Interrogating-CSCF) is the contact point within an
	operatorÆs 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 operatorÆs 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 behaves as a SIP Registrar.		the subscriber. It also acts as a SIP Registrar.
	IMS UEs use the GPRS as an access network for the IMS. Thus, a UE has		IMS capable UEs utilize the GPRS network as an access network for
	to have an activated PDP Context to the IMS before it can proceed to		accessing the IMS. Thus, a UE has to have an activated PDP Context to
	use the IMS services. The PDP Context activation is explained briefly		the IMS before it can proceed to use the IMS services. The PDP
	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 an 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-server
	in the Internet.		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.
	skipping to change at page 6, line 9		skipping to change at page 6, line 9
	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 network
	there is a GGSN (or separate GGSNs) that supports both connection to		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		IPv4 and IPv6 networks, it is possible to connect to both at the same
	time. Figure 3 depicts this scenario.		time. Figure 3 depicts this scenario.
	+-------------+		+-------------+
	| |		| |
	| UE | +------+		| UE | +------+
	| | | IPv4 |		| | | IPv4 |
	| | /| |		| | /| |
	|------|------+ / +------+		|------|------+ / +------+
	| IPv6 | IPv4 | +--------+ /		| IPv6 | IPv4 | +--------+ /
	skipping to change at page 6, line 31		skipping to change at page 6, line 31
	| |------------------------| |/		| |------------------------| |/
	| | |		| | |
	| IPv6 | GGSN |\		| IPv6 | GGSN |\
	|-------------------------------| | \		|-------------------------------| | \
	+-----------+ | | \ +------+		+-----------+ | | \ +------+
	| GPRS Core | | | \ | IPv6 |		| GPRS Core | | | \ | IPv6 |
	+-----------+ +--------+ | |		+-----------+ +--------+ | |
	+------+		+------+
	Figure 3: Dual-Stack Case		Figure 3: Dual-Stack Case
	However, the IPv4 addresses might be a scarce resource for the mobile		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		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,		to have a globally unique IPv4 address allocated all the time. Hence,
	the UE should either activate the IPv4 PDP Context only when needed,		the UE could either activate the IPv4 PDP Context only when needed,
	or be allocated an IPv4 address from a private address space.		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 first stages of IPv6 deployment, there are cases		Especially in the initial stages of IPv6 deployment, there are cases
	where an IPv6 node would need to connect to the IPv6 Internet through		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		a network that is IPv4. For instance, this can be seen in current
	fixed networks, where the access is provided in IPv4 only, but there		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		is an IPv6 network deeper in the Internet. This scenario is shown in
	the Figure 4.		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, and
	skipping to change at page 7, line 38		skipping to change at page 7, line 38
	| | +-----------+ | 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 GGSN,
	and a connection through the IPv6 network to the IPv4 Internet.		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 server in
	the legacy Internet. In the figure 6, this kind of possible		the legacy Internet. In the figure 6, this kind of possible
	installation is described.		installation is described.
	+------+ +------+		+------+ +------+
	| | | | +---+ +------+		| | | | +---+ +------+
	| UE |------------------| |-----| |----| |		| UE |------------------| |-----| |----| |
	| | +-----------+ | GGSN | | ? | | IPv4 |		| | +-----------+ | GGSN | | ? | | IPv4 |
	| IPv6 | | GPRS Core | | | | | | |		| IPv6 | | GPRS Core | | | | | | |
	+------+ +-----------+ +------+ +---+ +------+		+------+ +-----------+ +------+ +---+ +------+
	skipping to change at page 8, line 19		skipping to change at page 8, line 19
	Internet. Figure 7 depicts this configuration.		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 Transition scenarios with IMS		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
	skipping to change at page 9, line 12		skipping to change at page 9, line 12
	+------+ +------+ +-----+ +---+ +------+		+------+ +------+ +-----+ +---+ +------+
	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 two
	IMS islands are only connected via an IPv4 network such as the legacy		IMS islands are only connected via an IPv4 network such as the legacy
	Internet. See Figure 9 for illustration.		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 does not generate any additional security		This document describes possible transition scenarios for 3GPP
	considerations.		networks for future study. Solutions and mechanism are explored in
			other documents: The description of the 3GPP network scenarios does
			not have any security considerations.
	Authors		Authors
	This is 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>
	Niall Richard Murphy, Enigma Consulting Limited		Niall Richard Murphy, Enigma Consulting Limited
	<niallm@enigma.ie>		<niallm@enigma.ie>
	skipping to change at page 10, line 7		skipping to change at page 10, line 36
	<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		Acknowledgements
	The authors would like to thank Basavaraj Patil, Tuomo Sipil„, Fred		The authors would like to thank Basavaraj Patil, Tuomo Sipila, Fred
	Templin, Rod Van Meter, and Jens Staack for good input, and comments		Templin, Rod Van Meter, Pekka Savola, Francis Dupont, Christine
	that helped writing this document.		Fisher, Alain Baudot, Rod Walsh, and Jens Staack for good input, and
			comments that helped writing this document.
	Informative references
	[1] Wasserman, M., "Recommendations for IPv6 in Third Generation
	Partnership Project (3GPP) Standards", September 2002, RFC3314.
	Normative References		Normative References
	[2] 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.
	[3] 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.
	[4] 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.
	[5] 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 on SIP and SDP; Stage 3 (Release 5)", March 2002.		based on SIP and SDP; Stage 3 (Release 5)", March 2002.
			[5] Rosenberg J., Schulzrinne H., Camarillo G., Johnston A.,
			Peterson J., Sparks R., Handley M., Schooler E., " SIP: Session
			Initiation Protocol", RFC3261, June 2002.
			Informative references
			[6] Wasserman, M., "Recommendations for IPv6 in Third Generation
			Partnership Project (3GPP) Standards", RFC3314, September 2002.
	Editor's Address		Editor's Address
	Jonne Soininen		Jonne Soininen
	Nokia		Nokia
	313 Fairchild Dr. Phone: +1-650-864-6794		313 Fairchild Dr. Phone: +1-650-864-6794
	Mountain View, CA, USA Email: jonne.Soininen@nokia.com		Mountain View, CA, USA Email: jonne.soininen@nokia.com
End of changes.
This html diff was produced by rfcdiff 1.25, available from http://www.levkowetz.com/ietf/tools/rfcdiff/