IPv6 and IPv4 Coexistence

1. IPv6 and IPv4 Coexistence Motorola’s Views for Migration and Co-existence of 3GPP2 Networks to Support Both IPv4 and IPv6

2. IPv6 Migration Goals • Minimize Service Disruptions During Transition • Use IPv6 Expanded Address Space • Each MS can be assigned permanent IP address • Solves basic address availability problem • Greatly simplifies Mobile Terminated Data Services • Greatly simplifies operation of MIPv6 • Utilize Standards in Migration • 3GPP2 is likely to adopt IPv6 for the “All-IP” Network • IETF has developed several standards for migration from IPv4 to IPv6 • Other Advantages • Efficient routing and auto configuration mechanisms • Mobile IPv6 – simplifies mobility support in PDSN (no FA for MIPv6)

3. IPv6 IPv4 External Network Transport Network Core Network RAN Networks Border Router Border Router Access Gateway IPv6 Migration Overview • In Future: IPv6 will be implemented in mobiles, Core Networks, RAN and Transport Network • Issues primarily related to Core Network: • Interoperation of IPv4 and IPv6 networks during migration • Interoperation of IPv4 and IPv6 mobiles with IPv4 and IPv6 networks during and after migration • Implementation of QoS mechanisms between IPv4 and IPv6 networks • Interoperation of Mobile IP in IPv4 and IPv6 • Application Level Gateway Requirements

4. IPv6 Migration Fundamentals • Introduction of IPv6 Requires Coexistence of IPv4 and IPv6 • Both IPv4 and IP6 mobiles assumed to reside in network • External networks assumed to include both IPv4 and IPv6 • Timing of RAN and Transport Conversion Independent of use of IPv6 in Mobiles • RAN encapsulates PPP sessions between MS and PDSN • RAN does not examine contents of PPP packets • BR at Transport Network Interface can perform either encapsulation or translation • No mapping from MS QoS labeling and RAN QoS mechanisms • RAN QoS labeling determined during service negotiation • Migration Begins at the Core Networks • Core Network must migrate to support IPv6 mobiles when introduced • IPv6 mobiles Utilize existing IPv4 Applications

5. Core Network IPv6 Access Gateway IPv6 at Core Network Internal Services (IPv6/IPv4) IPv6 • Migration at the Core Network • Enables IPv6 address space for mobiles • Minimizes changes in the existing network • IPv4 encapsulation of MS bearer across RAN Network • PDSN and AAA must support IPv4, IPv6, MIPv4 and MIPv6 • Protocol Translation in servers provides interworking between IPv6 mobiles and IPv4 services • PPP Tunneling over IPv4 • IPv4/IPv6 over ATM/FR • Dual Stack Servers IPv4 Border Router IPv6/IPv4) External Network IPv4 Transport Network (ATM/FR) RAN Network IPv4 Border Router • Dual Stack Routers or • Protocol Translation at BR

6. IPv6 at Core Network • RAN will use IPv4 • PPP Encapsulation makes RAN independent of MS IP version • Dual Stack (IPv4 & IPv6) in Shared Devices • PDSN (upgraded from current PDSN) • Terminates PPP for both IPv4 and IPv6 mobiles • Supports MIPv6 address allocation for MIPv6 • Performs BR functionality between RAN and Transport Network • Encapsulation or dual stack transport across Core Network • Maps QoS marking between RAN and Transport Network • Shared network devices (Core Network.) • Common set of applications for IPv4 and IPv6 mobiles • Dual Stack IPv4/IPv6 • Encapsulation across Transport Network

7. IPv4/IPv6 over MPLS • PPP Tunneling over IPv6 • Dual Stack Servers Internal Services (IPv6/IPv4) IPv6 IPv4 External Network IPv6 Core Network IPv6 Border Router (IPv6/IPv4) AccessGateway RAN Network IPv6 Transport Network (MPLS) Border Router External Network IPv4 • Dual Stack Routers or • Protocol Translation at BR IPv6 at Transport and RAN • Migration of Transport and RAN Networks • Continues to Support IPv4 and IPv6 mobiles • Complete IPv6 transport network (RAN, Core Network) • Dual stack or IPv6 Encapsulation of IPv4 across Core Networks • Transport Network may migrate to support MPLS • MPLS mapping required at ingress nodes • Includes PDSN and BRs

8. IPv6 at Transport and RAN • RAN will use IPv6 • PPP Encapsulation makes RAN independent of MS IP version • Dual stack (IPv4 & IPv6) in shared devices • PDSN (upgraded from current PDSN) • All previous functionality plus • MPLS Ingress node functionality • PPP/IPv6 • Shared core network devices • No Change • Encapsulation across Transport Network • IPv4 and IPv6 over I.e. MPLS • Mapping at PDSN and BRs

9. PPP Tunneling External Network IPv4 Transport Network IPv6 Core Network IPv4 RAN Network IPv6 Border Router Border Router Access Gateway • IPv6 Encapsulation • IPv4 Edge Independent Core IPv6 Migration • Decision on IPv6 Migration of the RAN and Transport Networks can be independent of the Core Network Migration Decision • Driven by business strategy and performance issues • Transport and RAN could migrate before the Core Network but does not enable IPv6 mobiles

10. Summary • IPv6 Solves Limited Address Space Problem • Core Networks Support IPv6 when IPv6 Mobiles introduced and Continue to Support IPv4 Mobiles • Dual stack IPv6/IPv4 introduced in Shared Network Devices • Core Network Servers upgraded to support IPv6 in addition to IPv4 • Upgrade PDSN to support IPv6, MIPv6 in addition to IPv4 and MIPv4 • Core Network Routers IPv6 or IPv4 or Dual Stack • Transport and RAN Networks Migrate Based on Business Case • Independent of IPv6 support in mobile • PDSN remains dual stack and MIPv4 as long as IPv4 mobiles are present • Choice of dual stack routers or IPv6 encapsulation for migration • Decision based on performance and availability of IPv6

11. References • RFC 2893 Transition Mechanisms for IPv6 Hosts and Routers • RFC 2766 Network Address Translation - Protocol Translation (NAT-PT) • RFC 2765 Stateless IP/ICMP Translation Algorithm (SIIT) • RFC 2529 Transmission of IPv6 over IPv4 Domains without Explicit Tunnels • RFC 2473 Generic Packet Tunneling in IPv6 • RFC 2185 Routing Aspects Of IPv6 Transition • Draft RFC On overview of the introduction of IPv6 in the Internet • Draft RFC Overview of Transition Techniques for IPv6-only to Talk to IPv4-only Communication