This document discusses the need for and drivers towards IPv6 adoption. It notes that new mobile applications and services require more bandwidth than IPv4 allows. IPv6 provides a much larger address space and allows for always-on services without network address translation. The document outlines a phased approach to introducing IPv6 in mobile networks beginning with IPv6 in the user layer and terminal, followed by internal network upgrades. Initial IPv6 deployment is expected in 2003-2007 with a transition period before IPv6 is used mainly from 2014 onwards.

1. End-to-End and IPv6
John Loughney
john.loughney@nokia.com
IETF AAA WG Chair
IETF NSIS WG Chair
1 © NOKIA End-to-end and IPv6 / John Loughney

2. Technology Evolution from Circuits to
Packets Mobile
Multimedia
Personalised
Services Rich call
Mobile
Internet Location
Streaming Services
mCommerce
Wireless
Voice Browsing
Messaging
Handsets
GSM GPRS EDGE/WCDMA Network
13kbps 2mbps Bandwidth
Time
WLAN 53Mbps
2 © NOKIA End-to-end and IPv6 / John Loughney

3. New Applications and Services Need IPv6
• Messaging is important - text messages is a good starting point.
• 100 billion text messages (SMS) sent per month by the end of 2002
• Use of Multimedia messaging (MMS) is taking off.
• Instant Messaging, presence, Java applications, browsing, peer-
to-peer applications …
• Streaming with several media components, like audio & video.
• Location Based Services
• These all point for the need for IPv6.
3 © NOKIA End-to-end and IPv6 / John Loughney

4. Scalability of IPv4
• The current IP version, IPv4, was not designed for as large number
of Internet hosts as the Internet is experiencing today - the main
problem with IPv4 is its limited address space.
• IPv4 address space is being used with increasing speed and the
exhaustion of the IPv4 address space is unavoidable - it is difficult
to exactly predict when the IPv4 addresses run out
• The IPv4 address is 32 bits long and the theoretical maximum
for the number of addresses is 4.3 billion
• Currently, ~57% of the total address space is allocated
• Big portion of the allocated address space is used by the US
• Approximately 28% of the total IPv4 address space is advertised
(visible in the routing tables of Internet)
4 © NOKIA End-to-end and IPv6 / John Loughney

5. Drivers for IPv6
• Enough IP-addresses for everyone!
• 128 bit vs 32 bit addresses
• New always-on, push and person-to-person services
•No need for private network address space.
•No NATs.
• Easier management for users and network managers
•IPv6 autoconfiguration capabilites
• Enables true end-to-end security.
• Optimized mobility between various access networks
2E3D:34A1::129F...
1B3F:34E1::269B...
1F3F:34A1::879R...
1E3F:34D1::7890..
1E3F:34A1::629B...
1B3F:34B1::639A...
1E3F:34A1::6228...
4E3F:34A1::926F...
6E3C:34C1::639D...
1B3F:34C1::256F...
5 © NOKIA IPv6 & Multiaccess / John Loughney

6. Drivers for China
• IPv4 Addresses Currently Allocated (as of March 2003)
• China ~29.4 Million
• India ~ 2.6 Million
• Thailand ~ 1.7 Million
• Other Legacy Allocations (minimum)
• MIT ~17 Million
• IBM ~33 Million
• US Government ~168 Million
• UK Government ~33 Million
• Number of Chinese mobile subscribers
• 240 million (CDMA & GSM)
6 © NOKIA End-to-end and IPv6 / John Loughney

7. IPv6 in Mobile Networks
UMS
GGSN IMS
CSCF
• Phase 1: • IPv6 based User layer. This is visible to the services
and end-users. It is the biggest IPv6 driver by the
operators as this phase solves the end-user terminal
IP-address problems.
HLR MGW
BSC MSC
SGSN Server
• Phase 2:
RNC
GGSN IPv6
This is not visible to end-users, more just an operator internal
network implementation/arrangement issue
7 © NOKIA End-to-end and IPv6 / John Loughney

8. Introduction of IPv6 in a Nutshell
UMS
GGSN IMS
CSCF
• IPv6/IPv4 dual-stack as well as multiple PDP-context support in terminals
• IPv6 capable APNs + tunneling mechanisms in the GGSN (including provisioning)
• IPv6 support in the IMS as mandated in the 3GPP R5 standards as well as optionally in other
application servers (Web, email, streaming, etc.)
• Tunneling from GGSN to IMS possible with all types of IP-backbone architectures (IPoverSDH,
IPoverATM, with/without MPLS)
All the other IPv6 changes in the network are optional and related to phase 2
8 © NOKIA End-to-end and IPv6 / John Loughney

9. When can we expect 1st phase IPv6 ?
UMS
GGSN IMS
CSCF
Application
Servers
• Symbian 7.0 operating system supports IPv6
• Nokia packet core supporting 1st phase IPv6 already today
• Nokia IMS supports IPv6 already today in the pilot systems
• IPv6-stack support coming for services such as SIP,
browsing, streaming, email, etc.
9 © NOKIA End-to-end and IPv6 / John Loughney

10. Where IPv6 is deployed today ?
• Carriers, several commercial IPv6 networks exists today (NTT, Yusen, JCN…)
• Major initiative announced by US Department of Defense.
• Operating systems: Symbian, Microsoft XP, Linux, AIX, SUN, HP, MAC, Java
• Wireless: Nokia, Ericsson, J-Phone, Sharp, DoCoMo
• Games: Playstation, Xbox
• Europe, China, major investments in test networks (6NET, Euro6IX, and RITT)
See: http://www.ipv6forum.com/
10 © NOKIA IPv6 & Multiaccess / John Loughney

11. IPv6 Deployment Policy
Phase II
Phase Phase II
Phase II Phase III
Phase III Phase IV
Phase IV
(~2001)
(~2001) (2003~2007)
(2003~2007) (2008~2013)
(2008~2013) (2014~)
(2014~)
IPv4 Only IPv4 Ocean IPv4 Island
IPv6 Mainly
IPv4/IPv6 Transition Required
Experimental
IPv6 Network IPv6 Ocean
IPv6 Island
• Validation Commercial
• IMT2000 Service
• Operation IPv6 Service Complete native IPv6
• Translation Service
• Promotion (fixed/wireless)
11 © NOKIA IPv6 & Multiaccess / John Loughney

12. Private IPv4 addresses, NATs & related problems
• In an attempt to get more IPv4 addresses, private address space schemes have
been deployed
• Increasing the effective usage and life of the IPv4 address space
• Transport layer identifiers (TCP port numbers) are used to extend the address space
• In a private network, hosts may have only occasionally use of global addresses =>
public address is shared between multiple nodes
• NAT limitations and problems include:
• NATs break the end-to-end model of IP
• Nodes behind a NAT are not reachable from the global Internet
• NATs don’t fix everything, Application Level Gateways are needed.
• Not good for always on services such as instant messaging.
• Private address space and NATs force the use of a client-server model; peer-to-
peer applications are not feasible.
• NATs also increase the cost of customer service and add complexity
• deploying NATs can be costly, and harmful for operators' business
12 © NOKIA End-to-end and IPv6 / John Loughney

13. IPv6 Specifications
• IPv6 is specified by the IETF IPv6 (used to be IPng) Working Group
• IPv6 consists of numerous IETF RFCs and the basic specification is RFC 2460
• RFC 3316 "IPv6 for Some Second and Third Generation Cellular Hosts" defines
the minimum requirements for the 3GPP User Equipment (UE) IPv6 stack.
• 3GPP Release 99 is the first release where the IPv6 type of PDP context is
completely defined
• IP Multimedia Core Network Subsystem (IMS) is specified in the 3GPP Release
5
• 3GPP decided to have IPv6 as the only IP version in the IMS to avoid IPv4-IPv6
transition and interworking problems inside the IMS.
13 © NOKIA End-to-end and IPv6 / John Loughney

14. IPv6 in Standardization
• IPv6 Forum takes the lead in bringing the IPv6 message
to businesses and industry.
• 3GPP specifies use of IPv6 in 3rd Generation Networks.
3GPP Release 5 IMS is:
• based on IPv6 and SIP, with work being done in the IETF.
• “Cellular Hosts” use IPv6 for services provided by IMS.
• IPv4/IPv6 interworking principles is under study.
• Support for IPv6 since Release 99 (GPRS)
• 3GPP2 also supports IPv6.
• 3GPP, 3GPP2 both have official liasons with the IETF.
They both take IETF standards and reference them.
14 © NOKIA End-to-end and IPv6 / John Loughney

15. 3GPP transition scenarios
• Cellular networks have different requirements and scenarios of
transition than general Internet nodes would have
• 3GPP cellular networks IPv6 transition / interoperability has been
analyzed in the IETF v6ops Working Group
• Transition Scenarios for 3GPP Networks - RFC 3574
• 3GPP Analysis - draft-ietf-v6ops-3gpp-analysis-06.txt
• Main GPRS transition scenarios
1. Dual Stack UE connecting to IPv4 and IPv6 nodes
2. IPv6 UE connecting to an IPv6 node through an IPv4 network
• IMS transition scenarios:
1. UE connecting to a node in an IPv4 network through IMS
2. Two IPv6 IMS connected via an IPv4 network
15 © NOKIA End-to-end and IPv6 / John Loughney

16. Scenarios 1 and 2
1. Dual stack UE connecting to •Dual stack UE
IPv4 and IPv6 nodes •IPv4 PDP context to
(Peer) communicate with IPv4
IPv4 Node peers
network •IPv6 PDP context to
communicate with IPv6
GGSN
IP peers
(Peer) •(Configured) IPv6-in-IPv4
2G / 3G Edge IPv6 Node
mobile network Router network tunneling in the network
UE
•IPv6-in-IPv4 tunneling
from the UE in the case the
nw does not support IPv6
2. IPv6 UE connecting to IPv6 node
through an IPv4 network (Peer)
Node •(Configured) IPv6-in-
IPv6
IPv4 tunneling in the
IPv4 network network
GGSN IP network
IPv6 2G / 3G Edge
PDP mobile network Router
UE context
16 © NOKIA End-to-end and IPv6 / John Loughney

17. IMS Scenarios 1 and 2
1. UE connecting to a node in an
•"Interworking unit"
IPv4 network through IMS (Peer)
consisting of SIP ALG
Node
S-CSCF IPv4 for signaling traffic
SIP-ALG
network and a protocol
IPv6 PDP
context
P-CSCF IMS translator for the user
(IPv6-only) Translator data
GGSN •Solution is for limited
2G / 3G cases
mobile network
UE
2. Two IMS islands connected via an IPv4 network
(Peer) •(Configured) IPv6-in-
Node
IPv4 IPv4 tunneling in the
IMS
IMS
(IPv6- network to connect
(IPv6-
network
only) the IMS islands
GGSN
only)
IPv6 2G / 3G
PDP mobile network
UE context
17 © NOKIA End-to-end and IPv6 / John Loughney

18. From client-server to peer-to-peer
services
• Most Internet services today rely on the client-server model
• Peer-to-peer services are of end-to-end in nature
• There is no server between two end-hosts.
• Direct communication between two end nodes.
• More robust and flexible than client-server based services.
• Important requirement: the nodes involved in the peer-to-peer
communication have to be visible for the other nodes
• Examples of peer-to-peer services
• Content sharing applications & conferencing tools
• Voice over IP applications
• Peer-to-peer gaming
18 © NOKIA End-to-end and IPv6 / John Loughney

19. IPv6 enabling IMS and other peer-to-peer
services
• IPv6 with large enough address space assures a future-proof
environment to build peer-to-peer communication systems
• The 3GPP IMS is such a peer-to-peer application that requires
persistent, long-lived addressing
• IMS also relies on other protocols, such as SIP and Diameter
• SIP imposes an end-to-end architecture making the case for IPv6 even
stronger
• For having peer-to-peer connectivity the end-nodes of the
communication have to share the same IP version
• By selecting IPv6 from the beginning, misalignments caused by
the IP version are avoided
• This also facilitates interoperability in inter-operator cases
• IPv6 in 3GPP IMS simplifies the interworking between 3GPP IMS operators
19 © NOKIA End-to-end and IPv6 / John Loughney

20. Global SMS Growth
USA
(AWS, Cingular, T-Mobile,
Verizon)
1Q2002: 820 Million SMS’s
2Q2002: 1,600 Million SMS's
The main reason behind the
numbers is interoperability.
20 © NOKIA End-to-end and IPv6 / John Loughney

21. Conclusions
• IPv4 has acute address shortage problems, especially in
the cellular networks
• IPv4 NATs are a temporary relief to the IPv4 address exhaustion
- not the final solution
• NAT deployment is costly and harmful for operator business
• IPv6 with its large IP address space is a feasible solution
to the IP address exhaustion problem
• Peer-to-peer applications need to have global identifiers
to enable routing to the other peer
• In phone networks, this is the phone number, in IP networks it
is the IP address
• The IPv6 address space assures a future-proof platform
to build peer-to-peer communication systems - such as
the 3GPP specified IMS.
21 © NOKIA End-to-end and IPv6 / John Loughney