1. MIPSHOP – November, 2005 Event Services and Command Services for Media Independent Handover Presentation prepared by: Srini Sreemanthula Presented by: Greg Daley, with some additions MIPSHOP IETF 64

2. MIPSHOP – November, 2005 IEEE 802.21 Introduction IEEE 802.21 WG defines media independent handover (MIH) services that enable handoffs from one link technology to another involving subnet changes MIH services aid in handoff based on existing mobility management protocols MIH services are classified as 3 types MIH Information Services MIH Command Services MIH Event Services

3. MIPSHOP – November, 2005 What MIH provides MIH service carry L2 information that is processed locally or carried to some other network node, remotely MIH Services enable two facets of inter- technology handover Inter-technology Network selection Handover control

4. MIPSHOP – November, 2005 ES/CS Introduction Event Services (ES) provide: indications from one layer or functionality to another about changes in the connectivity state. Remote ES convey information from one network node to another Command Services (CS) provide: mechanisms for controlling handovers or functions aiding handovers. mechanisms to establish, redirect, or remove state in either the network or mobile node, so that handovers occur smoothly. Remote CS convey information from one network node to another

5. MIPSHOP – November, 2005 Motivations 802.21 functional definitions are to enable two scenarios Terminal centric/controlled Network centric/controlled

6. MIPSHOP – November, 2005 Terminal Controlled Handover Terminal makes all the decisions of network selection and initiates HO control Can utilizes native L2 signaling or L2/L3 MIH ES/CS and L3 IS services Used in operator, enterprise or individual user scenarios

7. MIPSHOP – November, 2005 Network Controlled Handover Network makes decisions of network selection in coordination with the terminal and initiates HO control Assumption is that network selection is in core network (beyond L2) HO control resides where MME (common to both accesses) resides (beyond L2) This requires that L3 MIH IS, ES and CS services are available Important for operator models with multiple access technologies

8. MIPSHOP – November, 2005 Motivation Summary Higher layer MIH ES/CS services provide architectural flexibility for 802.21 deployment does not need 802.21 in certain link technologies ES/CS are utilized for both network selection and handover control Applicable to network entity common to both media types Not scalable to provision these functions within subnet Easier and faster 802.21 adoption in other SDO e.g. 3GPP Can coexist or share functions with MIH ES/CS at L2

9. MIPSHOP – November, 2005 ES/CS Service Model Other Sources MIHF (ES) MIH (ES) Other Sources Remote ES Other triggers Link Layer Link Layer Other triggers Link Indications Link Indications Network Node Network Node Other layers/ functions MIHF (CS) MIH (CS) Remote CS Commands MME Link Layer Link Commands Network Node Network Node Event Service model Command Service Model

10. MIPSHOP – November, 2005 Usage Models Direct and Proxy models Direct model Proxy model MIHF UE MIHF MME Remote ES/CS MIHF UE MIHF proxu MIHF Remote ES/CS

11. MIPSHOP – November, 2005 NW Initiated NW Selection MAC Layers Beacon 802.16-AN802.11-ANMIHF UE UE DL-Burst* Link-Detect 802.11-AN Beacon MMEMIHF NW (IS) MIH-Register-Event.Resp() Link-Event.Detect(link_info) Network Operator Link-Event.Detect(link_info) MIH-Register-Event.Req() MIH-Info.Resp MIH-Info.Req Unfavorable Network Favorable Network => Selection UE Discovery and Registration MIH-Info.Resp MIH-Info.Req

12. MIPSHOP – November, 2005 NW Controlled HO MIHF UE Mobile IP UE Operator Network HA 802.11 Network New-FA802.11-AN MIH-Remote-Link-Switch.Req(802.11 nwk) L2-Procedures (Security, Re-association, QoS Neg.) Link-Event-Up(802.11 nwk) MIH-Link-Event-Up FBU L3-switch.Ind 802.11 MAC MIH-Remote-Link-Switch.Resp Release Mobile-IP Signaling MIH signaling over new link Legend MME Network Selection Link-Associate Proxy Rtr Solicitation Proxy Rtr Advertisement Mobile IP update procedure over new link

13. MIPSHOP – November, 2005 Remote ES/CS Feasibility Discussion relevant due to: Adoba, B., "Architectural Implications of Link Indications draft-iab-link-indications-03.txt", June 2005. Explicit signaling required Intertechnology handover may not result in IP subnet change Mitigation of security issues Trust issues Mapping of identifiers Done at the UE

14. MIPSHOP – November, 2005 Explicit Signalling Command and event signalling Implicit signalling possible when path changes or link-aware routing metrics from access network Explicit signaling required Intertechnology handover may not result in IP subnet change May inform devices of mobility management issues which aren’t apparent in the current access net Needs safeguards to ensure damping/robustness

15. MIPSHOP – November, 2005 Identifier Mappings May be possible to make identifier mappings Appl/ Trans/ Netw MIHF ES/CS Link- Layers Mapping of Local Identifiers MME Discovery Registration Authentication Security Association Media independent host ID Mobile NodeNetwork

16. MIPSHOP – November, 2005 ES/CS Higher Layer Requirements Work is similar to IS higher layer MIIS for Identifying usage scenarios Provisioning models e.g. proxy and direct Finalizing ES/CS MIH functionality Message sequences, message types, data elements associated with each message Other higher layer requirement categories Transport Layer Discovery Registration and Deregistration Capability negotiation Security Reliability and failure recovery