North American IPv6 Summit, June 17, 2004.

1. IPv6 in 2G and 3G Networks
John Loughney
North American IPv6 Forum 2004

2. • Introduction
• Relevant IPv6 Status in the IETF
• Relevant IPv6 Status in 3GPP
• Relevant IPv6 Status in 3GPP2
• Conclusion

3. What IPv6 Brings
• Resolves the address space limitation of IPv4
• Enables global peer-to-peer services across different networks
• What is possible with IPv4 in limited scale, is globally possible with IPv6
• Less complexity in network maintenance
• No private address spaces
• No NATs (savings both in equipment and maintenance costs)
• End-to-end security features are easier to deploy with global addresses
EN D- EN D PHON E CALL
TO-
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EN D- EN D I M ULTI EDI CON N ECTI
TO- P M A ON
1080:1: 2:
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4. IPv6 Products…Gaining Momentum
• Symbian 7.0 supports IPv6.
• Microsoft WinXP and Windows server 2003 supports IPv6.
• Linux, HP-UX, AIX, VMS, & Solaris 8 shipping IPv6.
• Most infrastructure vendors support IPv6
• Nokia shipping IPv6 in IPSO 3.3
• Cisco announced IPv6 support from IOS 12.2(1)T.
• Applications
• Sendmail, Apache Web server and Squid webcache are IPv6 enabled.
• New breed of applications such as 3Degrees are IPv6 only.
• For a current list see:
• http://www.ipv6forum.com/navbar/links/v6apps.htm
• http://www.ipv6.org/v6-apps.html

5. Dual Stack Handsets
• One common misconception is that IPv6 stack,
especially dual stack, is heavy on terminals.
• IPv6 TCP/IP stack size is comparable to IPv4 TCP/IP
stack.
• Dual stack (IPv4 and IPv6) size is NOT multiple times the
size of IPV4 stack.
• Dual stack (v4/v6) is comparable (only about 15% bigger than)
IPv4 TCP/IP stack.
• Direct correspondence between IPv4 socket
library and IPv6 socket library – porting does not
require major changes in applications.

6. Applications Benefiting
from IPv6
• Peer-to-peer type of applications.
• Push-to-Talk
• SIP based multimedia and VoIP
• Peer-to-peer games
• IPsec VPNs

7. IPv6 in

8. IPv6 in 3GPP Specifications
• Support for IPv6 (for user traffic) was fully introduced in
3GPP Release 99.
• IPv6 address allocation mechanism was updated in 2002
to allocate a globally unique (/64) prefix (instead of a
single address) for every primary PDP context.
• IP Multimedia Subsystem (IMS) - multimedia service
infrastructure introduced in Release 5 specifies IPv6 as
the only IP version in the IMS to avoid IPv4-IPv6
transition and interworking problems.

9. Transition to IPv6 in 3GPP networks
• 3GPP networks have specific requirements and
scenarios for transition.
• Analyzed in the IETF v6ops Working Group
• Transition Scenarios for 3GPP Networks - RFC 3574
• 3GPP Analysis - draft-ietf-v6ops-3gpp-analysis-10.txt
• 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
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
• IMS transition scenarios:
1. UE connecting to a node in an IPv4 network through IMS
2. Two IPv6 IMS connected via an IPv4 network

10. PoC and NATs
The UDP inactivity timer in NAT can cause the public
Ther can be NO NATs
e UDP port 6538 to be assigned to a different mobile, if
bet een t PoC
w he the mobile does not send any data within a certain
Clent Prvat I addr s 1
i , i e Pv4 es t m i and PoC
er nal amount of time, e.g. in 40 seconds …
Ser !
ver PoC Ser ,Publc I addr s 3
ver i Pv4 es
N UDP por = 6538
t
A
Clent Prvat I addr s 2
i , i e Pv4 es T
• Even though PoC connections use a PoC server in the network, private addresses
cause problems similar to other SIP signaling cases.
• UDP inactivity timers are used with NATs and cause some problems:
The mobile would need to send keep-alive packets to every used public UDP
socket in about 30 seconds. This generates unnecessary “overhead” traffic and
would be very bad for the battery life.
The mobiles could easily use up all of the operators public IPv4-addresses due
to the refreshments, the public UDP ports can’t be assigned to new mobiles.
Thus, for performance reasons, NATs should not be used for PoC !!

11. Inter-Operator PoC Connectivity
with IPv4
Oper or 1
at Oper or 5
at
Prvat I
i e Pv4 Publc I
i Pv4 Publc I
i Pv4 Prvat I
i e Pv4
”NAT” ”NAT”
Oper or 2
at Oper or 6
at
Prvat I
i e Pv4 Publc I
i Pv4 Publc I
i Pv4 Prvat I
i e Pv4
”NAT” ”NAT”
Oper or 3
at Oper or 7
at
Publc I
i Pv4 Publc I
i Pv4
Prvat I
i e Pv4 Prvat I
i e Pv4
”NAT” ”NAT”
Oper or 4 Publc I
at Publc I
i Pv4
Oper or 8
at
Prvat I
i e Pv4 i Pv4 Prvat I
i e Pv4
”NAT” ”NAT”
• Lots of PoC users require port reservations that can use much of the
operator’s public IPv4 address space.
• Current GPRS networks use private addresses almost exclusively.

12. IMS - IP Multimedia Subsystem
Fixed
GGSN net or
w k
I S
M
( Pv6)
I
W LAN
• IP Multimedia Subsystem (IMS) is an architecture for mobile multimedia
services.
• IMS is an application that needs IPv6 to be successful and widely deployed.
• For roaming and inter-operator cases.
• IMS uses Session Initiation Protocol (SIP)
• IMS enables peer-to-peer applications

13. IMS with IPv6
M ul i
t -count y/
r oper or SI
at P-connectviy net k
it wor
SI Si
P gnalng:
i
CSCF CSCF
A’ addr =
s ess
Publc I
i Pv6 Addr 1
ess
Publc
i
I outng dom ai
P-r i n
(nt -oper or
i er at
connectons
i )
M edi f om B t A:
a r o
Sentt Publc I
o i Pv6 Client, Public IPv6 address 2
Client, Public IPv6 address 1
Addr 1
ess
• Peer o-peer connect ons can be expanded t i er
-t i o nt -oper or and
at
i er
nt -count y whenever t oper or want t do s …
r he at s o o

14. Turning IPv6 on
is quite simple
IPv6 basics (for IMS services) • GGSN & SGSN
supporting IPv6
HLR needs to support provisioning of DNS supporting IPv6 APNs & • HLR, DNS and Firewall
PDP-contexts with type = IPv6 IPv6 address records (AAAA sw update
records) • HLR, DNS and GGSN
configurations
• IPv6 server site has an
IPv6-capable router
APNs supporting IPv6 and IPv6 capable • IPv6-capable terminals
DNS IPv6 over IPv4 tunneling. servers (e.g. IMS)
DNS
HLR
HLR
CPS site router
with IPv6 over IPv4
CSCF tunneling
(may not be needed)
SGSN
I S APN
M I S APN
M SGSN
Nat ve I or
i Pv6
I
Pv6-i Pv4
n-I
tunnels GGSN
GGSN
Support for IPv6 PDP IPv6 capable Firewalls
context signaling in SGSN. IPv6 capable terminals

15. IPv6 in

16. IPv6 in 3GPP2
• 3GPP2 IS-835C specifies Simple IPv6
• /64 addresses through PPP.
• no duplicate address detection.
• Mobile IP
• MIPv6 is now RFC 3775!
• 3GPP2 will incorporate this now that MIPv6 has after RFC status in
the IETF.
• 3GPP2 standardization plan for MIPv6 is to be part of IS-835 Rel D
(to be published mid-2004)
• 3GPP2 may also need some context transfers between PDSN’s
when MIPv6 is deployed.
• 3GPP2 and 3GPP are Co-operating on IMS
• 3GPP2 IMS supports both IPv4 and IPv6

17. Transition Scenarios for
3GPP2 Operators
• Many possible scenarios for network transition.
• Simple IPv4 -> Simple IPv6
• Mobile IPv4 -> Simple IPv6
• Mobile IPv4 -> Mobile IPv6
• Various choices for upgrading network
• Upgrade mobile terminals and PDSNs and some services to dual-
stack. Leave operator core network as IPv4.
• Upgrade only mobile terminals and some services to dual-stack.
Employ transition mechanism on mobile.

18. I and I Net k
Pv4 Pv6 wor
DST
IPv4/IPv6 Host IPv6 Host
Operator EDGE
PDSN Operator ROUTER
Network IPv6
IPv6
Network
Internet
Internet
ROUTER1
IPv4/IPv6 Host
ROUTER2
IPv4
IPv4
Operator Operator
Internet
Internet
IPv6 Services IPv4 Services
Operator Network IPv4 Host
IPv4/IPv6 Host

19. Dual-Stack
• Mobile Perspective
• Mobile can open an IPv4 only, IPv6 only or both IPv4 and IPv6
connection with the PDSN.
• Mobile can add or remove IP or IPv6 NCPs at any time.
• Mobile will use DNS to determine the address family of the end-host.
• Mobile will decide to use either IPv4 or IPv6 based on the address
family of the end-host.
• Network Perspective
• PDSN and Edge router must be upgraded to dual-stack.
• PDSN can tunnel IPv6 packets over IPv4 if the operator core
network is IPv4 only.
• PDSN IPv4 -> dual-stack upgrades are usually software upgrades.

20. Dual Stack Access
DST IPv6
packets IPv4/IPv6 Host IPv6 Host
Operator EDGE
PDSN Operator ROUTER
Network IPv6
IPv6
Network
Internet
Internet
I t
Pv6 unneled
over I
Pv4 ROUTER1
IPv4/IPv6 Host
ROUTER2
IPv4
IPv4
Operator Operator Internet
IPv4 Services Internet
IPv6 Services
Operator Network IPv4 Host
I packet
Pv6 s
I packet
Pv4 s IPv4/IPv6 Host

21. Advantages of Dual-Stack
• Does not require tunneling on the wireless link.
• Pricing issues on wireless usage.
• Bandwidth and latency issues on the wireless link
• Services can be upgraded to IPv6 in a phased manner.
• Use of DNS records (AAAA or A records) is the central
control point for transitioning services.
• Software upgrades required for network entities, for the most
part.

22. Summary
• IPv6 resolves IPv4 address space limitations and
enables peer-to-peer connectivity in global scale
• Co-existence of IPv4 and IPv6.
1.Enable IPv6 in end nodes and networks
2.Make applications use IPv6.
• Enabling IPv6 in mobile network is relatively straight-forward.
• IMS era is here
• Commercial IMS network elements & IMS services (file sharing, peer-
to-peer gaming, ...) piloting in 2004
• Wide-scale, commercial IMS deployment in from 2005 onwards
• IPv6 is an important enabler for IMS
However, IPv6 can be used for more than just IMS.
• Connecting People