1. IEEE 802.21 MEDIA INDEPENDENT HANDOVER DCN: 21-13-0174-00-MISU Title: Interworking Service Architecture and Requirements Date Submitted: September 17, 2013 Presented at IEEE 802.21 session #58 in Nanjing Authors or Source(s): Yoshihiro Ohba (Toshiba), Ruben Salazar (Landis+Gyr), Randy Turner (Landis+Gyr), Subir Das (ACS) Abstract: This contribution describes an architecture and requirements on a new media-independent service 121-13-074-00-MISU

2. 2 IEEE 802.21 presentation release statements This document has been prepared to assist the IEEE 802.21 Working Group. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.21. The contributor is familiar with IEEE patent policy, as stated in Section 6 of the IEEE-SA Standards Board bylaws and in Understanding Patent Issues During IEEE Standards Development http://standards.ieee.org/board/pat/faq.pdf> Section 6 of the IEEE-SA Standards Board bylawshttp://standards.ieee.org/guides/bylaws/sect6-7.html#6http://standards.ieee.org/board/pat/faq.pdf

3. Use Case presented in March 2013 (DCN 21-13-0053) 21-13-074-00-MISU3

4. Heterogeneous Network Use Case It is becoming common that multiple different access technologies are available in the vicinity of end-devices However, each end-device may support only one access technology especially if it is a constrained device 21-13-074-00-MISU4 802.15.4 PLC3G/LTE Core Network Access Networks End Devices Overlapping coverage Gateway

5. Heterogeneous Network Use Case (cont’d) If the reachability to the core network from an end-device via its access technology is lost, then communication to the end-device is totally lost Expecting constrained end-devices to have multiple interfaces are not a viable solution Increasing gateway redundancy is also expensive Some sort of “interworking” among heterogeneous networks would be needed for increasing network availability for constrained end-devices with a minimum cost 21-13-074-00-MISU5 802.15.4 PLC3G/LTE Core Network Access Networks End Devices Overlapping coverage Gateway

6. Interworking Service Architecture and Requirements 21-13-074-00-MISU6

7. Functional Elements for Interworking Service Serving Network (SN): An access network to which Interworking Service is provided Interworking Network (IN): An access network existing in the vicinity of Serving Network to provide Interworking Service to the Serving Network End Device (ED): A node that is physically connected to Serving Network Interworking Relay (IWR): A node that is physically connected to both Serving Network and Interworking Network to exchange Serving Network MAC frames with Interworking Gateway using a Virtual Link. More than one Interworking Relay may be connected to the Serving Network Interworking Gateway (IWG): A node that is physically connected to Interworking Network to exchange Serving Network MAC frames with Interworking Relay through a Virtual Link. Interworking Gateway may also be connected to an external network 21-13-074-00-MISU7

8. Interworking Architecture 21-13-074-00-MISU8 ED IWR IWG SN (e.g., 802.15.4) Virtual Link IN (3G, etc.) SN: Serving Network IN: Interworking Network ED: End Device IWR: Interworking Relay IWG: Interworking Gateway Serving Network MAC frame Serving Network MAC entity

9. Interworking Service Requirements R1: Interworking Service MUST provide a mechanism to exchange SN MAC frames between IWR and IWG over a virtual link R2: Interworking Service MUST provide a mechanism to dynamically establish and terminate a virtual link between IWR and IWG R3: Interworking Service MUST provide a mechanism to enable and disable exchanging SN MAC frames over a virtual link established between IWR and IWG R4: Interworking Service MUST provide a mechanism for IWR to discover IWG R5: Interworking Service MUST provide a mechanism for IWR to register and deregister with IWG R6: Interworking Service MUST provide a mechanism to manage quality of service of a virtual link established between IWR and IWG R7: Interworking Service MUST be designed such that existence of IWR and IWG is transparent to EDs (New) R8: Interworking Service MUST provide multicast traffic exchange over a virtual link established between IWR and IWG (New) R9: Interworking Service MUST provide a mechanism to filter packets exchanged over a virtual link (New) R10: Interworking Service MUST provide a mechanism to secure packets exchanged over a virtual link and packets used for controlling a virtual link 21-13-074-00-MISU9

10. Protocol Stack 21-13-074-00-MISU10 Application Transport IPv6 6LoWPAN SN MAC SN PHY Application Transport IPv6 6LoWPAN SN MAC Interworking Layer (802.21.1) Transport IPv4 or IPv6 IW MAC IW PHY Protocol Stack for SN devices Protocol Stack of IWR and IWG over IW MAC/PHY interface (for Virtual Link control & data)

11. Call Flow (IWR-initiated Virtual Link Set-Up) 21-13-074-00-MISU11 IWR VL_Setup request VL Setup IWG VL_Setup response VL Setup

12. Call Flow (IWG-initiated Virtual Link Set-Up) 21-13-074-00-MISU12 IWR VL_Setup request VL Setup IWG VL_Setup response VL Setup

13. Call Flow (IWR-initiated Virtual Link Teardown) 21-13-074-00-MISU13 IWR VL_Teardown request VL Teardown IWG VL_teardown response VL Teardown

14. Call Flow (IWG-initiated Virtual Link Teardown) 21-13-074-00-MISU14 IWR VL_Teardown request VL Teardown IWG VL_Teardown response VL Teardown

15. Call Flow (Transmitting Data over Virtual Link) 21-13-074-00-MISU15 IWR VL_Data indication IWG

16. Attributes 21-13-074-00-MISU16 VL_Setup request VL Setup response VL_ Teardown request VL_Teardown response VL_Data indication IWG MAC Address X X XX SN MAC TypeX Virtual Link IDXXX X StatusXX SN MAC frame X

17. Summary and next step An architecture and requirements for interworking service have been proposed to realize the use case on high-availability M2M network Write-up specification 21-13-074-00-MISU17