1. 1 3GPP TSG CT Chairman 3GPP TSG CT Chairman Hannu Hietalahti Hannu Hietalahti 3GPP presentation Architecture evolution Moscow, October 2008

2. 2 Migration from GSM to multi-access IP multimedia From GSM to multi-access SIM/USIM/ISIM support Security evolution System Architecture Evolution (SAE) IMS Multi-mode terminals and networks –Service continuity –Multiple registration –Voice Call Continuity –CS Fallback –Network selection Contents

3. 3 Continuous improvement of access technologies Provision of services over any access network...and let’s make it IP all the way to the terminal ! Common Core network GSM 900 3GHSPA WLAN E-UTRAN EDGE GSM 1800 GPRS GSM 1900 GSM ph.1 R97 R98 R99 Rel-5/6 Rel-6/7 Rel-8 and onwards WiMAX? ? From GSM to multi-access Fixed Packet Cable

4. 4 SIM / USIM / ISIM support GSM Ph.2 – R98R99 – Rel-4Rel-5 – Rel-7Rel-8 -> GSM phoneUMTS 3G phoneIP MultimediaSAE GSM phase 2 Mandatory SIM No USIM support Optional GPRS (R97 ->) WCDMA or EDGE Mandatory SIM USIM support is: Mandatory for WCDMA Optional for GSM/EDGE IMS Mandatory USIM No SIM specs Optional support of legacy SIM ISIM support mandatory for IMS ME WLAN (Rel-6) SAE USIM mandatory for SAE access 3G AKA security SIM access not allowed any more No need to update legacy USIM IMC as alternative to ISIM for non- 3GPP access ???

5. 5 Security evolution Phase 2 SIM 2G AKA SIM SRES Kc RAND RES Ck Ik RES Ck Ik USIM Application 3G AKA ISIM Appl UICC Smartcard, R99 -> 2G AKA RAND SRES Kc 2G AKA SIM Appl SRES Kc RAND 3G AKA Authentication Request (RAND ) SIP 401 Unauthorise d, AUTN GSM security SIM application in UICC 3G AKA in UICC IMS 3G AKA in ISIM +AUTN SIM security in USIM RAND+ AUTN

6. 6 LTE = E-UTRAN = evolved radio network –Megabit class data rates –Short delays –Short transition from idle to active SAE = System Architecture evolution –Evolved IP oriented multi access architecture E-UTRAN integrates only to SAE, A/Gb or Iu not possible Strongly IP based PS only network SAE covers both 3GPP and non-3GPP access technologies Seamless roaming between E-UTRAN, 2G and 3G (tight interworking) Loose interworking with non-3GPP accesses Currently work is progressing on GTP for intra-3GPP mobility and IETF based mobility for non-3GPP mobility –The main Architecture specifications 23.401 and 23.402 frozen in June 2008 –Protocol work is ongoing with the goal to freeze it in December 2008 System Architecture Evolution (SAE)

7. 7 Deployments are expected to start with overlapping cellular coverage –E-UTRAN overlapping with legacy 3GPP GERAN / UTRAN coverage –E-UTRAN overlapping with legacy 3GPP2 coverage –Multi-mode networks and terminals E-UTRAN is a packet-only radio with no CS capacity Initially E-UTRAN is foreseen as “islands” in the sea of legacy cellular access –Mobility between E-UTRAN and legacy access is required –Mobility between PS and CS domains is required –Multi-mode terminals expect to use PS coverage where available –Desire to keep the connectivity and services SAE/LTE Deployment

8. 8 Internet IP Multimedia Subsystem (IMS) PS domain IP Multimedia service platform Based on open IETF standards –End to end IP (SIP) –Multi access GPRS, I-WLAN, fixed xDSL, Packet Cable defined More access technologies to follow... Circuit-switched network (2G or 3G) IP Multimedia Core PSTN IP connectivity (GPRS, 3G,...) Find & route to destination User data Any IP connectivity (3G, WLAN,...) End-to-End IP services

9. 9 3GPP members, 3GPP2, WiMAX forum, ETSI TISPAN and CableLabs contribute to 3GPP common IMS specifications –Different requirements are supported in common implementation All IMS specifications are harmonized to 3GPP specifications –Common parts are defined in 3GPP specifications only Core IMS entities (CSCFs, AS, UE IMS client,...) + agreed common functions –Other organisations either reference or re-use 3GPP specification as it stands –Any changes or additions in the Common IMS area are made in 3GPP All 3GPP members can contribute on their favourite work items Ongoing work initiated by 3GPP members, CableLabs, 3GPP2 and ETSI TISPAN –The scope and coverage of Common IMS have been agreed by the SDOs Common version of IMS specifications in Rel-8 –Business or architecture specific additions to 3GPP Common IMS are possible outside the agreed Common IMS area Common IMS

10. 10 Call control protocols –E-UTRAN is a PS only radio, speech and other services are IMS based –PS domain IMS uses SIP protocol for call control (3GPP TS 24.229) –CS domain uses Call Control defined in 3GPP TS 24.008 Voice Call Continuity –Domain transfer of ongoing call –Typically from E-UTRAN to 2G or 3G access CS fallback –Paging the mobile in E-UTRAN to start CS service in 2G or 3G access –Not an E-UTRAN service, but fallback to existing service via 2G/3G IMS service continuity –IMS service between E-UTRAN and other PS only, such as WLAN IMS Centralized Service Control (ICS) –Common telephony services between CS and PS domain Multi-mode, Service continuity

11. 11 Multi-mode, IMS registration in Rel-7 When S-CSCF detects that the same UE registers again, it considers this as an update and overwrites existing registration In some cases it may not be possible to de-register when changing from one access technology to another –UE might lose radio coverage before being able to de-register S-CSCF detects that the registration is from the same UE based on the same privateID, which is practically a device-ID UE (privateID-A) S-CSCF REGISTER 1 (privateID-A, IPaddress: 1.2.3.4) loss of radio UE registered with 1.2.3.4 REGISTER 2 (privateID-A, IPaddress: a.b.c.d) UE registered ONLY with a.b.c.d – REGISTER 1 got overwritten with REGISTER 2

12. 12 Multi-mode, IMS Multiple registration, Rel-8 A UE is able to register the same public user identity with multiple IP addresses at the same time Used e.g. for IMS Service Continuity (e.g. handing over from I-WLAN to GPRS) No gap in reachability of the mobile S-CSCF P-CSCF 1 P-CSCF 2 GPRS IP: 1.2.3.4 UE-A HSS I-WLAN IP: a.b.c.d user1 / 1.2.3.4 / UE-A user1 / a.b.c.d / UE-A

13. 13 Multi-mode, Single Radio Voice Call Continuity Transfer from E-UTRAN to GERAN with active call (not all entities shown) PLMN serving remote user MSC server IMS MSC E-UTRAN 2G or 3G measurements HO required MME relocation request prepare HO relocation response session transfer HO command HO complete

14. 14 Multi-mode, CS fallback Directing the UE from E-UTRAN to 2G/3G for CS service PLMN serving remote user MSC E-UTRAN 2G or 3G MME SETUP call setup paging paging resp. SETUP

15. 15 Multi-mode, Network selection Network selection comprises two parts –Network operator selection (the goal, based on commercial agreement) Home operator determines which visited operators are preferred –Access technology selection (the means, based on technical criteria) Serving visited operator determines access technology, frequency band and cell Multi-mode phones supporting many access technologies are a new challenge Network selection within each technology is defined for 3GPP and non-3GPP accesses The combination of multiple technologies is undefined Two approaches are foreseen in Rel-8 –3GPP network selection procedures are extended to cover any non-3GPP system that supports ITU-T defined concepts of MCC and MNC –For others the ANDSF can (optionally) download network selection policy Access technology preference, policy for changing access technology, etc. MCC = Mobile Country Code MNC = Mobile Network Code ANDSF = Access Network Discovery and Selection Function

16. 16 PLMN Selector (USIM): VPLMN5 VPLMN2 VPLMN1 Multi-mode network selection, Outbound roaming example HPLMN VPLMN1 VPLMN2 VPLMN1 CDMA VPLMN2 GERAN VPLMN1 E-UTRAN ? HPLMN has not configured RAT priority for this VPLMN HPLMN is not available Prioritized VPLMNs are listed with no associated RAT in PLMN selector with access technology: –VPLMN5 is not available –VPLMN1 is available –VPLMN2 is available VPLMN2 is selected via 2G, 3G or E-UTRAN –USIM configured RAT preference possible After PLMN selection normal idle mode is resumed –Cell & RAT may change within the selected PLMN –Background scan for higher priority network RAT = Radio Access Technology, PLMN = Public Land Mobile Network VPLMN2 UTRAN VPLMN2 E-UTRAN

17. 17 Thanks for your attention ! More information at www.3gpp.org

18. 18 Architecture Annex: 3GPP and non-3GPP access architecture

19. 19 Mobility anchor Packet routing Idle mode packet buffering & DL initiation Legal interception UE IP address allocation Packet screening & filtering Policy enforcement Charging support Legal interception NAS signaling+sign. security Mobility between 3GPP ANs Idle mode UE reachability P-GW and S-GW selection SGSN selection at HO Authentication Bearer establishment SAE architecture (23.401) User plane security (UMTS AKA) Signaling security (UMTS AKA)

20. 20 S2 for connectivity via non- 3GPP acces Trusted IP access directly to P-GW Untrusted IP access via ePDG SAE non-3GPP access (23.402)