System Enhancements for Accessing Broadcast Services in All-IP - PDF document

System Enhancements for Accessing Broadcast Services in All-IP Networks  Patrick Stupar Krishna Pandit and Wolfgang Granzow  Patrick Stupar, Krishna Pandit, and Wolfgang Granzow  Qualcomm CDMA Technologies GmbH Motivation 54.2 % 36 4 % 36.4 % 23.1 % 18.0 % Source: Internet Users Forecast by Countries, eTForecasts & Computer Industry Almanac, February 2008  Over 4 billion cellular subscriptions  Over 3 billion of these based on 3GPP standardized technology  Increase of IP based services accessed by users through 3GPP device  3GPP solution: definition of all-IP network P. Stupar, K. Pandit, and W. Granzow: 2 System Enhancements for Accessing Broadcast Services in All-IP Networks

All IP Network definition  “All IP Network” (AIPN) paradigm  The deployment relies on the usage of Internet Protocol (IP) on all the network nodes  Every base station implements IP functionalities (acts as an IP access router)  Inter orking bet een different mobile s stems is based on IP Interworking between different mobile systems is based on IP  Enables new technologies deployment with minimal extensions to the core network reducing CAPEX Public Internet P bli I t t PGW Trusted 3GPP GPRS 3GPP Enhanced non-3GPP Core Packet Core Access GERAN ePDG UTRAN Access Access E-UTRAN Access Untrusted non- 3GPP Access (E.g. WiFi) P. Stupar, K. Pandit, and W. Granzow: 3 System Enhancements for Accessing Broadcast Services in All-IP Networks Broadcast technology integration in an AIPN  Challenges for integration of broadcast technology/services in an AIPN  The broadcast services rely on a central entity acting as content provider  Solutions may require synchronized data packets delivery (see e.g. evolved Multimedia Broadcast Multicast Service - eMBMS)  Adopted approach: interworking between broadcast system and AIPN  Adopted approach: interworking between broadcast system and AIPN  Provisioning of broadcast services to the user over different access systems  Depending e.g. on the user scenario, network load conditions, and radio conditions, the access system can be dynamically changed • • Reference architectures: 3GPP Evolved Packet Core (EPC) and eMBMS Reference architectures: 3GPP Evolved Packet Core (EPC) and eMBMS Content Provider BM-SC Public Internet PGW MBMS-GW Trusted 3GPP GPRS non-3GPP 3GPP Enhanced Core Packet Core (EPC) Packet Core (EPC) Access Access GERAN ePDG UTRAN Access Access E-UTRAN Access Untrusted non- 3GPP Access (E.g. WiFi) (E.g. WiFi) P. Stupar, K. Pandit, and W. Granzow: 4 System Enhancements for Accessing Broadcast Services in All-IP Networks

EMBMS reference architecture model - Provides the eNodeB - Provides the eNodeB MBSFN A MBSFN Area with the multicast related (Multimedia Broadcast multicast information (defined by MBMS-GW) service Single Frequency Network) - Admission control - Allocation of radio Allocation of radio resources - Membership function - Session and Transmission function - Service Announcement function - Content synchronization - IP multicast distribution of MBMS user plane data (M1 reference point) E-UTRAN EPC Public Internet P. Stupar, K. Pandit, and W. Granzow: 5 System Enhancements for Accessing Broadcast Services in All-IP Networks Interworking scenarios and problem statement  Interworking scenarios  Resources optimization - counting – Number of users in a MBSFN area is low – Unicast channel can be used to deliver the broadcast service Unicast channel can be sed to deli er the broadcast ser ice  Retention priority – Network can not deliver through broadcast channel all the broadcast services – Broadcast services not delivered through broadcast channel are unicasted Broadcast services not delivered through broadcast channel are unicasted  Problem statement  In the above scenarios the service may stop being available over the broadcast channel  Interrupting the service would mean a bad user experience and is unacceptable for operators  WLAN interworking is one option to enable service continuity  An architecture and protocols to enable WLAN interworking with the MBMS bearer An architecture and protocols to enable WLAN interworking with the MBMS bearer service need to be designed P. Stupar, K. Pandit, and W. Granzow: 6 System Enhancements for Accessing Broadcast Services in All-IP Networks

Possible architectural approaches  Architecture 1  Re-usage of existing interfaces for EPC-WLAN interworking  Architecture 2  D fi i i Definition of an interface between ePDG/WLAN and MBMS-GW f i f b PDG/WLAN d MBMS GW  For each considered architectures there are 2 possible solutions based on the IP transmission mode transmission mode  Unicast vs. multicast P. Stupar, K. Pandit, and W. Granzow: 7 System Enhancements for Accessing Broadcast Services in All-IP Networks Architecture 1 – Re-use non-3GPP access architecture - IP Access Router for 3GPP access - Connects the 3GPP network to public Internet (through SGi) - Anchor mobility among 3GPP and Anchor mobility among 3GPP and non-3GPP accesses End point of data traffic encryption tunnel  Two possible flavors  Multicast routing in the network between PGW and ePDG/WLAN  Unicast tunneling between PGW and UE P. Stupar, K. Pandit, and W. Granzow: 8 System Enhancements for Accessing Broadcast Services in All-IP Networks

Architecture 1 – Considerations  IP Multicast based approach  The service packets are transmitted on IP multicast through the SGi interface  The PDN-GW forward the IP multicast packets to the UE  Impact on the e isting architect re Impact on the existing architecture – Multicast routing protocol capability is required in • PDN-GW • Network implementing the SGi interface Network implementing the SGi interface • Network between the ePDG and the PDN-GW – Multicast routing protocols usage must not taken as granted • Several networks do not implement it  IP Unicast based approach  The BM-SC transmits the packets in IP unicast using as IP destination the UE address  Impact on the existing architecture – The PDN-GW needs to be informed whether the packets need to be sent over Th PDN GW d t b i f d h th th k t d t b t WLAN or EPC P. Stupar, K. Pandit, and W. Granzow: 9 System Enhancements for Accessing Broadcast Services in All-IP Networks Architecture 2 – New interface WLAN and MBMS-GW  ePDG interface can be based on GTP   M1 interface between MBMS GW and eNodeB is GTP based M1 interface between MBMS-GW and eNodeB is GTP based P. Stupar, K. Pandit, and W. Granzow: 10 System Enhancements for Accessing Broadcast Services in All-IP Networks

Architecture 2 – Considerations  IP Multicast based approach  The service packets are transmitted on IP multicast through the M1 interface as when sent to the eNodeB   Impact on the existing architecture Impact on the existing architecture – M1 interface between MBMS-GW and ePDG – Control plane interface between ePDG and MME – If the usage of WLAN needs to be selective (e.g. streaming service requires E- g ( g g UTRAN only) BM-SC needs to be “technology” aware  IP Unicast based approach  IP unicast based M1 for E-UTRAN is not specified – No point-to-point bearer is created by the MBMS-GW in case of E-UTRAN N i t t i t b i t d b th MBMS GW i f E UTRAN  If M1 interface can be unicast for E-UTRAN, impact on the existing architecture are: – Control plane interface between ePDG and MME – If the usage of WLAN needs to be selective (e g streaming service requires E- If the usage of WLAN needs to be selective (e.g. streaming service requires E UTRAN only) BM-SC needs to be WLAN aware P. Stupar, K. Pandit, and W. Granzow: 11 System Enhancements for Accessing Broadcast Services in All-IP Networks Comparison of 2 architectures PROS CONS Re-use non-3GPP Requires no new Require multicast routing access access - multicast multicast interfaces interfaces protocol deployment protocol deployment •Requires no new Re-use non-3GPP interfaces Non-optimal delivery of traffic p y access - unicast access unicast •Minimal impact to existing •Minimal impact to existing architecture Extensions to existing Interface WLAN and Optimized integration architecture (control plane architecture (control plane MBMS-GW - (traffic not routed through MME-ePDG and user plane multicast the internet) ePDG-MBMS-GW) Same as m lticast based Same as multicast based Same as multicast based Same as m lticast based Interface WLAN and solution (M2 interface can solution (M2 interface can MBMS-GW - unicast implement unicast or implement unicast or multicast) ) multicast) ) P. Stupar, K. Pandit, and W. Granzow: 12 System Enhancements for Accessing Broadcast Services in All-IP Networks