IEEE 802.21 MEDIA INDEPENDENT HANDOVER Title: Multi-Radio Power Conservation Management (MRPM) Date Submitted: March 3 2009 Presented at IEEE 802 plenary in Vancouver Authors or Sources: Dennis Edwards, Behcet Sarikaya, James Han, Junghoon Jee, Anthony Chan Abstract: 802.21 MRPM Tutorial 21-09-0030-02-mrpm 1

Contents Overview Existing power management in individual radio technology Power Management Problems Basic MIH capabilities MRPM Principle MRPM Use cases 21-09-0030-02-mrpm 2

Contents Overview Existing power management in individual radio technology Power Management Problems Basic MIH capabilities MRPM Principle MRPM Use cases 21-09-0030-02-mrpm 3

Multi-Radio Activities in IEEE 802.21 Optimized Handover between different technologies IEEE 802.21, Published in Jan-2009 Security Signaling during Handovers IEEE 802.21a, PAR Approved in Dec-2008 Handovers to Broadcast Technologies IEEE 802.21b, PAR Approved in Jan-2009 Battery Power Conservation in Multi-Radio devices MRPM (IEEE 802.21c) IEEE 802.21 : to support handover optimization (using L2 trigger, neighboring network map and MIH handover procedure) IEEE 802.21a : to reduce the latency during authentication and key establishment for handovers, and to provide secure MIH protocol exchange and enable authorization for MIH services IEEE 802.21b : 21-09-0030-02-mrpm 4

Contents Overview Existing power management in individual radio technology Power Management Problems Basic MIH capabilities MRPM Principle MRPM Use cases 21-09-0030-02-mrpm 5

Broad category of power saving modes (varies in specific network technology) Service Actively running a network application Standby Always ready to communicate Sleep Wake at scheduled times to check whether to communicate Off Power Power Power wake Sleep interval Battery life Battery life Battery life sleep 21-09-0030-02-mrpm 6

Power management in individual technology Multi-radio device is becoming more popular. Each technology has own power management features, which may include paging and wake, location update, sleep mode protocol, and other power saving operations. Multi-radio managers used in devices are proprietary. Each radio power is currently managed independently from other radios and networks 802.16 3GPP; 3GPP2 Other Nets 802.11 Multi-radio device 21-09-0030-02-mrpm 7

Power Management in 802.11/16: optimized within its own technology Mode/state Tx Rx Registration Control signaling Bearer traffic Time to wake-up 802.11 Active Full Yes N/A Power save (PS) No DTIMs DTIMs only Long Extended PS (Sleep) Some DTIMs > PS Off Power-up 802.16 Sleep Class 1 Partial Quick Class 2 Class 3 Idle Wake-up paging only 21-09-0030-02-mrpm 8

Power Management in 3GPP/3GPP2: optimized within its own technology Mode/state Tx Rx Registration Control signaling Bearer traffic Time to wake-up 3GPP2 Active Full Yes N/A Control hold Partial Quick Suspended > Control hold Dormant Little V. Limited Burst Long Off No Power-up 3GPP Connected Idle (camped) I (not camped) Long (scan/camp) 21-09-0030-02-mrpm 9

Battery life depends on many things Different modes of operation in different technologies + – - Fast call set up PTT (interactive) Active - Play back-start 802.16 Sleep? 802.11 Sleep? + – - Record-start Power consumption Response time 802.11 Idle? CDMA Sleep? + – - Webpage-start - Streaming-start + – - Background-start Off Battery life also depends on data rate, discharge rate, temperature, charge count, etc. Power consumption and response time are the emphases here. 21-09-0030-02-mrpm 10

Power saving modes in 802.11 and their response times In sleep mode (extended PS mode), may adjust sleep interval, but no Group Transient Key update. In power-saving (PS) mode, response time is several beacon intervals: fraction of a second. Automatic PS delivery (APSD) mode: Use algorithm to adjust PS time to finer granularity or when there are packets to transmit In active mode, response time depends on traffic and QoS class. Location and BSS change: during wake at the designated DTIM 10s Sleep interval 1s PS mode DTIM interval 100ms Beacon interval APSD time granularity CSMA/CA (Active mode) 10ms Response Time 1ms 21-09-0030-02-mrpm 11

Power saving modes in 802.16m and their response times Location determination >10s Idle mode (not registered): periodically listens to paging broadcast over a large area, performs location update, Sleep mode (registered): variable sleep interval (2-1024 frames, frame duration =2-20 ms), with variable connections: Type I: for NRT-VR, BE Type II: for RT-VR, UGS Type III: management operations, periodic ranging (for HO) Deep sleep 10s Sleep interval Multicast channel reselection 1s Idle to active (802.16e) 100ms Handover delay Idle to active (802.16m) 10ms Response Time 1ms 21-09-0030-02-mrpm 12

Contents Overview Existing power management in individual radio technology Power Management Problems Rapid Power Consumption by Multiple Radios Power Consumption during Non-Active Application Service Negative Performance Impact Basic MIH capabilities MRPM Principle MRPM Use cases 21-09-0030-02-mrpm 13

1. Rapid Power Consumption by Multiple Radios 802.16 3GPP; 3GPP2 802.16 3GPP; 3GPP2 Power 802.11 802.11 + – + – + – + – Battery life Drains battery fast if power consumption is optimized only within each individual technology Different technologies have different modes of operation each with different power consumption Battery life Service Standby Sleep Battery life (approx. # only for cellular ) 1 radio A1 2 hrs (talk time) 2 radios 3 radios 24 hrs (customer expectation) A1,A2 12 hrs A1,A2,A3 8 hrs 6 days (customer expectation) 3 days 2 days 21-09-0030-02-mrpm 14

2. Power consumption during Non-Active Application Service Power required for scanning is about 60% of the power required for receiving data rate of 1Mb/s Source: D21-C.3: Multi-Access Evaluation and Assessment, Ambient Networks Phase 2, Dec. 2007 21-09-0030-02-mrpm 15

3. Negative Performance Impact Power management can extend battery lifetime, however, it can negatively impact performance Typing “ls” on HP iPAQ 3870 handheld with Cisco 350 card Source: Self-tuning wireless network power management, MobiCom’03 21-09-0030-02-mrpm 16

Contents Overview Existing power management in individual radio technology Power Management Problems Basic MIH capabilities MRPM Principle MRPM Use cases 21-09-0030-02-mrpm 17

802.21 media independent handover (MIH) services Layer 3 and Above Layers SIP MIH Function Information Service MIH_SAP Event Service MIP HMIP Command Service LLC_SAP LLC_SAP Network 1 (e.g., 802.16) Network 2 (e.g., 3GPP) Information Service MIH_LINK_SAP MIH_LINK_SAP Event Service Command Service Handover 21-09-0030-02-mrpm 18

802.21 MIH at devices and at networks enables collaboration between them Higher Layer Higher ayer MIHF MIHF IP IP Logical Connection between peer nodes MIH_NET_SAP MIH_NET_SAP MAC MAC PHY PHY 802.11u 802.16g 21-09-0030-02-mrpm 19

Contents Overview Existing power management in individual radio technology Power Management Problems Basic MIH capabilities MRPM Principle MRPM Use cases 21-09-0030-02-mrpm 20

Multi-Radio Power Management (1) Purpose: Enhance the user experience by extending the battery operating life of multi-radio mobile devices. Scope: Define mechanisms to reduce power consumption of multi-radio mobile devices on heterogeneous IEEE 802.21 compliant networks. Not in Scope: Enhancements to the MAC/PHY of individual access technologies for making them more power efficient are outside the scope of this project. 21-09-0030-02-mrpm 21

Multi-Radio Power Management (2) Enables to put inaccessible or unused radios into lower power states (Off or Deep-sleep) Enables to activate the deactivated radios when required Within coverage area, application requirement, network capacity Enables to select best radio and its corresponding power state for an application service Enables to minimize the time in accessing the network when activating a radio Acquiring configuration parameters to access the network in advance 21-09-0030-02-mrpm 22

Multi-Radio Power Management (3) Single radio Multiple radios Multiple radios with MRPM Power Power Power negligible Battery life negligible Battery life Battery life 21-09-0030-02-mrpm 23

Multi-Radio Power Management (4) QoS Operator Policy Network Selection Policy Control Multi Interface Control Resource Management operates in a power efficient way! MIH (Neighboring Network MAP) MIH MRPM - Device power characteristics - Each I/F status (power state) MRPM Location Network Accessibility Power States Power States Control WiFi WiMAX 3GPP Radio (WiFi, WiMAX, 3GPP) Mobile Node Network Node 21-09-0030-02-mrpm

Contents Overview Existing power management in individual radio technology Power Management Problems Basic MIH capabilities MRPM Principle MRPM Use cases Minimizing Power Consumption Network Selection Lowest power configuration Use of deep sleep state 21-09-0030-02-mrpm 25

Use case 1: Minimizing Power Consumption Paging Area B Paging Controller Location update to WiMAX paging controller. Cell 4 Paging Area A AP 4 WiFi is turned-off still WiFi is turned-off. Cell 3 AP 5 Cell 5 AP 3 Cell 2 AP 1 Cell 1 AP 6 AP 2 Cell 6 App. is terminated Active Cell 7 AP 7 Paging Area C 21-09-0030-02-mrpm

Use Case 2: Network Selection Incoming Traffic WiFi is selected MRPM User Request to activate WiFi CT Paging Area B Which interface? Paging Controller Cell 4 Paging Area A AP 4 AP 5 Cell 3 Cell 5 AP 3 Cell 2 Cell 1 AP 6 AP 1 AP 2 Cell 6 Cell 7 WiFi is activated. AP 7 Paging Area C 21-09-0030-02-mrpm

Turning off radio David has a multi-radio mobile terminal with WiFi and Cellular interfaces. He is working at his office where the WiFi network is available. He starts an application session through the WiFi interface. The application session is terminated. As the terminal moves out of the WiFi coverage area, the WiFi interface is turned off to save the power consumption. Wi-Fi 21-09-0030-02-mrpm 28

Power Management based on User Preference David is on trip and he has a GSM roaming phone with WiFi. He prefers VoIP call over WiFi to calling over GSM due to the high roaming fee. WiFi interface is usually deactivated for its power conservation while GSM interface maintains its connectivity to the network. GSM Wi-Fi GSM Wi-Fi Kim makes a VoIP call to David. MIH PoS on the network checks whether David can access the WiFi network at his current location. If WiFi is accessible, MIH PoS on network requests to wake up WiFi interface via GSM interface. The WiFi interface is activated and conversation begins. 21-09-0030-02-mrpm 29

Network Selection based on up Network Resource Here comes a multimedia call toward David. The multimedia call requires higher bandwidth that cannot be provided by the current cellular network resource. David’s WiFi accessibility is checked. If David is within the WiFi coverage area, the multimedia call is processed through the WiFi interface. GSM Wi-Fi 21-09-0030-02-mrpm 30

Power Management based on Application Features David has a smart phone. (802.11/802/16/3GPP). He usually prefers to use a stock ticker program whenever his phone is attached to 802.11 network. Stock Ticker requires a low data rate (≈ 10pkt/sec). The delay of 802.11 PSM can be tolerated by the stock ticker application. So, the stock ticker application can present stock information during PSM. MIH User (Stock Ticker) MIH Function (MRPM) 802.11 802.16 3GPP Purpose: Conclusion First UseCase 21-09-0030-02-mrpm 31

Lowest power configuration? There are tradeoffs between power-saving and operational capabilities. The operations involved include: Handover Response to paging Location update, etc. The capability to perform each operation while optimizing power saving depends on Application requirements 21-09-0030-02-mrpm 32

Lowest power configuration Lowest power configuration? Need to meet application response time requirements >10s Background-start Mean Web think time 10s Streaming-start Webpage-start Record-start (interactive) 1s Play back-start (interactive) PTT (interactive) Sleep  on Delay (conversational) Fast call set up Hold  on 100ms Lip synchronization (IEEE C802.20-03/13r1) 10ms Jitter in voice and video 1ms 21-09-0030-02-mrpm 33

Lowest power configuration? MRPM may involve network to Network (MIH) can be informed of the response time requirements of the applications Knowing the response times of the different modes for different interfaces is useful to figure out the multiple interface power saving strategy to trade-off between response time and power saving and to determine the appropriate sleep interval. Network can be informed of the actual multiple-interface power saving states of the MN to determine how to reach the MN (whether to wake, and wake which interface) 21-09-0030-02-mrpm 34

Use of deep sleep state with MRPM Normal sleep (for an “on” radio) Shorter response time to paging Power Short sleep interval Battery Life Deep sleep (for an “off-available” radio) Long response time is sufficient for location update Power Long sleep interval Battery Life 21-09-0030-02-mrpm 35

Use of deep sleep (no service) Single radio Power Power wake sleep Each radio controlled independently Sleep interval Battery life sleep Battery life Power Deep sleep Potential MRPM solution Deep sleep or off sleep Battery life 21-09-0030-02-mrpm 36

Use of deep sleep state with MRPM Battery life for multiple interfaces Service Standby Normal sleep Deep sleep Off Battery life (approx. numbers only for cellular ) A 24 hrs 2 radios A,B 12 hrs MRPM B 24 – 3.5 hrs 24 hrs almost Sleep 6  24 hrs (customer expectation) 3  24 hrs 6  24 hrs almost 6  24 hrs 1 radio >> 6  24 hours (assumptions) 21-09-0030-02-mrpm 37

anthonychan@huawei.com; jhjee@etri.re.kr; PAR/5C is at: https://mentor.ieee.org/802.21/file/08/21-09-0021-00-mrpm-revised-par-and-5c.doc Feedback: anthonychan@huawei.com; jhjee@etri.re.kr; STDS-802-21@LISTSERV.IEEE.ORG 21-09-0030-02-mrpm 38

Thank you 21-09-0030-02-mrpm 39

Backup Difference with 802.21 baseline Information Service Baseline 802.21 is mainly for optimizing handover, so we focused on the information delivery toward MN when there’s an active radio. Static heterogeneous coverage information is maintained in the Information Server Delivers the heterogeneous coverage information usually when MN requests using the current active radio MN’s request contains the current location of MN Information Server can identify the MN’s location when MN sends a query to Information Server MRPM enables to track heterogeneous network coverage information with lowest multi-radio power states Keep minimal idle state interface(s) for location tracking Put unused or inaccessible radio interfaces into lower power states Activate the deactivated radio interfaces only when required 21-09-0030-02-mrpm