1. IEEE 802.21 MEDIA INDEPENDENT HANDOVER
Title: Multi-Radio Power Conservation Management (MRPM)
Date Submitted: March
Presented at IEEE 802 plenary in Vancouver
Authors or Sources: Dennis Edwards, Behcet Sarikaya, James Han, Junghoon Jee, Anthony Chan
Abstract: MRPM Tutorial
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2. Contents
Overview
Existing power management in individual radio technology
Power Management Problems
Basic MIH capabilities
MRPM Principle
MRPM Use cases
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3. Contents
Overview
Existing power management in individual radio technology
Power Management Problems
Basic MIH capabilities
MRPM Principle
MRPM Use cases
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4. Multi-Radio Activities in IEEE 802.21
Optimized Handover between different technologies
IEEE , Published in Jan-2009
Security Signaling during Handovers
IEEE a, PAR Approved in Dec-2008
Handovers to Broadcast Technologies
IEEE b, PAR Approved in Jan-2009
Battery Power Conservation in Multi-Radio devices
MRPM (IEEE c)
IEEE : to support handover optimization (using L2 trigger, neighboring network map and MIH handover procedure)
IEEE a : 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 b :
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5. Contents
Overview
Existing power management in individual radio technology
Power Management Problems
Basic MIH capabilities
MRPM Principle
MRPM Use cases
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6. 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
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7. 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
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8. 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
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9. 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)
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10. 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.
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11. 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
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12. 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 ( 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
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13. 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
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14. 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
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15. 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
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16. 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
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17. Contents
Overview
Existing power management in individual radio technology
Power Management Problems
Basic MIH capabilities
MRPM Principle
MRPM Use cases
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18. 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., )
Network 2
(e.g., 3GPP)
Information
Service
MIH_LINK_SAP
MIH_LINK_SAP
Event
Service
Command
Service
Handover
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19. 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
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20. Contents
Overview
Existing power management in individual radio technology
Power Management Problems
Basic MIH capabilities
MRPM Principle
MRPM Use cases
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21. 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 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.
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22. 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
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23. Multi-Radio Power Management (3)
Single radio
Multiple radios
Multiple radios with MRPM
Power
Power
Power
negligible
Battery life
negligible
Battery life
Battery life
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24. 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
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25. 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
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26. 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
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27. 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
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28. 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
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29. 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.
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30. 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
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31. 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 network.
Stock Ticker requires a low data rate (≈ 10pkt/sec).
The delay of 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
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32. 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
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33. 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 C /13r1)
10ms
Jitter in voice and video
1ms
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34. 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)
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35. 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
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36. 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
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37. 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)
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38. anthonychan@huawei.com; jhjee@etri.re.kr;
PAR/5C is at:
Feedback:
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39. Thank you
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40. Backup Difference with 802.21 baseline Information Service
Baseline 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
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