GARUDA: Achieving Effective Reliability for Downstream Communication in Wireless Sensor Networks Seung-Jong Park, Member, ...
<ul><li>Data delivery can be critical </li></ul><ul><li>Guaranteed sink-to-sensors </li></ul><ul><li>Reliable downstream d...
Outline http://wshlab2.ee.kuas.edu.tw
Introduction <ul><li>Energy-aware protocols isn’t enough </li></ul><ul><ul><li>Wireless Channel Errors </li></ul></ul><ul>...
<ul><li>Delivered reliably  </li></ul><ul><ul><li>Control code </li></ul></ul><ul><ul><li>Query-data </li></ul></ul><ul><u...
<ul><li>Assumptions </li></ul><ul><ul><li>Downstream reliability </li></ul></ul><ul><ul><li>Communication and node failure...
<ul><li>Single-/First-Packet Delivery </li></ul><ul><ul><li>Benefits </li></ul></ul><ul><ul><ul><li>Robust fading effects ...
Framework <ul><ul><li>Wait for first package(WFP) Pulse Transmission </li></ul></ul>http://wshlab2.ee.kuas.edu.tw CS: carr...
<ul><li>Loss Recovery Servers: Core </li></ul><ul><ul><li>Goal </li></ul></ul><ul><ul><ul><li>Minimize the retransmission ...
Framework <ul><ul><li>Instantaneous Core Construction </li></ul></ul><ul><ul><ul><li>Sink </li></ul></ul></ul><ul><ul><ul>...
Framework <ul><ul><li>Loss Recovery for Core Nodes </li></ul></ul><ul><ul><ul><li>Upstream core nodes </li></ul></ul></ul>...
Framework <ul><ul><li>Loss Recovery for Noncore Nodes </li></ul></ul><ul><ul><ul><li>Snoops all (re)transmissions from its...
Performance evaluation <ul><li>Evaluation of Single-Packet Delivery </li></ul>http://wshlab2.ee.kuas.edu.tw  
Performance evaluation <ul><li>Evaluation of Multiple-Packet Delivery </li></ul>http://wshlab2.ee.kuas.edu.tw (100 * 3.14 ...
Performance evaluation <ul><li>Microscopic Analysis </li></ul><ul><ul><li>Optimality of the core </li></ul></ul><ul><ul><l...
Performance evaluation <ul><li>Evaluation of Variants </li></ul><ul><ul><li>Reliable Delivery within a Subregion </li></ul...
Performance evaluation <ul><ul><li>Minimal Set of Sensors </li></ul></ul>http://wshlab2.ee.kuas.edu.tw
Conclusions <ul><li>Future work </li></ul><ul><ul><li>With mobility and in the presence of multiple sinks. </li></ul></ul>...
Q & A Thank for your attention
Framework  –D? <ul><li>Two-Phase Loss Recovery </li></ul><ul><ul><li>A-Map(Availability Map) </li></ul></ul><ul><ul><li>Fu...
Performance evaluation <ul><li>Simulation Environment </li></ul><ul><ul><li>網路地形 </li></ul></ul><ul><ul><ul><li>100 node,6...
Other reliability semantics <ul><li>Reliable Delivery within a Subregion </li></ul><ul><ul><ul><li>Without loss (100%) </l...
<ul><ul><li>Environment considerations </li></ul></ul><ul><ul><ul><li>Scarcity of bandwidth and energy. </li></ul></ul></u...
Related work  -D <ul><li>Before </li></ul><ul><ul><li>Efficient flooding </li></ul></ul><ul><ul><ul><li>Classify: probabil...
<ul><li>Challenges </li></ul><ul><li>Environment Constraints </li></ul><ul><ul><li>Not relying on statically constructed m...
Problem definition  -D <ul><li>Acknowledgment (ACK)/NACK Paradox </li></ul><ul><ul><li>NACK </li></ul></ul><ul><ul><ul><li...
Problem definition  -D <ul><li>Reliability Semantics </li></ul>http://wshlab2.ee.kuas.edu.tw
GARUDA Design Element  -D <ul><ul><ul><li>前言 </li></ul></ul></ul><ul><ul><ul><ul><li>機制 Two-phase loss recovery strategy t...
GARUDA Design Element  -D <ul><ul><li>Instantaneous Core Construction </li></ul></ul><ul><ul><ul><li>First packet delivery...
GARUDA Design Element  -D <ul><li>Multiple Reliability Semantics  </li></ul><ul><ul><li>SPT(short path tree) can shortly d...
<ul><li>Loss Recovery Servers: Core </li></ul><ul><ul><li>Goal </li></ul></ul><ul><ul><ul><li>Minimize the retransmission ...
Design Element -D <ul><ul><li>A=PAPX(MDS) </li></ul></ul><ul><ul><li>B=OPT(MSC) </li></ul></ul><ul><ul><li>Cost = A/B </li...
Design Element <ul><li>Loss Recovery Process </li></ul><ul><ul><li>Out-of-Sequence Packet Forwarding with  </li></ul></ul>...
Design Element <ul><li>Reliable Single-/First-Packet Delivery  ? No relation </li></ul><ul><ul><li>Predict ,  重傳  when the...
Implicit ACK http://wshlab2.ee.kuas.edu.tw 802.11 Implicit ACK Gain
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  • GARUDA

    1. 1. GARUDA: Achieving Effective Reliability for Downstream Communication in Wireless Sensor Networks Seung-Jong Park, Member, IEEE, Ramanuja Vedantham, Member, IEEE, Raghupathy Sivakumar, Senior Member, IEEE, and Ian F. Akyildiz, Fellow, IEEE Report : Hsiung Chun Kuei IEEE TRANSACTIONS ON MOBILE COMPUTING, VOL. 7, NO. 2, FEBRUARY 2008
    2. 2. <ul><li>Data delivery can be critical </li></ul><ul><li>Guaranteed sink-to-sensors </li></ul><ul><li>Reliable downstream data </li></ul>Abstract http://wshlab2.ee.kuas.edu.tw
    3. 3. Outline http://wshlab2.ee.kuas.edu.tw
    4. 4. Introduction <ul><li>Energy-aware protocols isn’t enough </li></ul><ul><ul><li>Wireless Channel Errors </li></ul></ul><ul><ul><li>Congestion and Contention </li></ul></ul><ul><ul><li>Broadcast Storm </li></ul></ul>http://wshlab2.ee.kuas.edu.tw
    5. 5. <ul><li>Delivered reliably </li></ul><ul><ul><li>Control code </li></ul></ul><ul><ul><li>Query-data </li></ul></ul><ul><ul><li>Response result about sensor match data </li></ul></ul><ul><li>Cornerstones of design </li></ul><ul><ul><li>Reliable short-message. </li></ul></ul><ul><ul><li>V irtual infrastructure – core </li></ul></ul><ul><ul><li>Two-stage negative acknowledgment (NACK) </li></ul></ul>Introduction http://wshlab2.ee.kuas.edu.tw
    6. 6. <ul><li>Assumptions </li></ul><ul><ul><li>Downstream reliability </li></ul></ul><ul><ul><li>Communication and node failures </li></ul></ul><ul><ul><li>100 % reliable message delivery </li></ul></ul><ul><ul><li>Message size less then one packet </li></ul></ul><ul><ul><li>Network model is static </li></ul></ul>Framework http://wshlab2.ee.kuas.edu.tw
    7. 7. <ul><li>Single-/First-Packet Delivery </li></ul><ul><ul><li>Benefits </li></ul></ul><ul><ul><ul><li>Robust fading effects and collision. </li></ul></ul></ul><ul><ul><ul><li>Implicit NACK fit in short package. </li></ul></ul></ul><ul><ul><ul><li>Result in low energy. </li></ul></ul></ul>Framework http://wshlab2.ee.kuas.edu.tw
    8. 8. Framework <ul><ul><li>Wait for first package(WFP) Pulse Transmission </li></ul></ul>http://wshlab2.ee.kuas.edu.tw CS: carrier sensin
    9. 9. <ul><li>Loss Recovery Servers: Core </li></ul><ul><ul><li>Goal </li></ul></ul><ul><ul><ul><li>Minimize the retransmission overheads. </li></ul></ul></ul><ul><ul><ul><li>Constructed in a manage dynamic topology </li></ul></ul></ul><ul><ul><li>Rationale of Core </li></ul></ul><ul><ul><ul><li>MDS(Minimum Domination Set) </li></ul></ul></ul><ul><ul><ul><li>MSC(Minimum Set Cover) </li></ul></ul></ul>Design Element http://wshlab2.ee.kuas.edu.tw
    10. 10. Framework <ul><ul><li>Instantaneous Core Construction </li></ul></ul><ul><ul><ul><li>Sink </li></ul></ul></ul><ul><ul><ul><ul><li>band-ID(bId) = 0 </li></ul></ul></ul></ul><ul><ul><ul><li>In 3i bands </li></ul></ul></ul><ul><ul><ul><ul><li>Radom wait, and no invite message from the same band. It will be candidate. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Maintain upstream core’s information </li></ul></ul></ul></ul><ul><ul><ul><li>In 3i+1 </li></ul></ul></ul><ul><ul><ul><ul><li>S 0 is S 1 ’s core ,when the new S 0 ’ core invite again, S 1 will trade off each other by delay time. </li></ul></ul></ul></ul><ul><ul><ul><li>In 3i+2 </li></ul></ul></ul><ul><ul><ul><ul><li>When time out, the node will sends an anycast “core solicitation message” to 3(i+1) nodes. And then respond after a random waiting delay. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Boundary condition : not invite form core. Such condition can be detected. </li></ul></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    11. 11. Framework <ul><ul><li>Loss Recovery for Core Nodes </li></ul></ul><ul><ul><ul><li>Upstream core nodes </li></ul></ul></ul><ul><ul><ul><li>Downstream core nodes </li></ul></ul></ul><ul><ul><ul><ul><li>A-map:myBM (successfully received packet),totBM(received and requested packets) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>If A-map is from a valid source. Updating to totBM. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Send request , and set expire time. If receive the feedback to update to myBM </li></ul></ul></ul></ul><ul><ul><ul><ul><li>If no response from upstream core, requiring to default upstream core. </li></ul></ul></ul></ul><ul><ul><ul><li>Intermediate noncore nodes </li></ul></ul></ul><ul><ul><ul><ul><li>Set the vFlag to NULL when identifier is equal 3 </li></ul></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    12. 12. Framework <ul><ul><li>Loss Recovery for Noncore Nodes </li></ul></ul><ul><ul><ul><li>Snoops all (re)transmissions from its core node. </li></ul></ul></ul><ul><ul><ul><li>After Period core presence timer, sends an explicit request to core node that response with A-map </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    13. 13. Performance evaluation <ul><li>Evaluation of Single-Packet Delivery </li></ul>http://wshlab2.ee.kuas.edu.tw  
    14. 14. Performance evaluation <ul><li>Evaluation of Multiple-Packet Delivery </li></ul>http://wshlab2.ee.kuas.edu.tw (100 * 3.14 * 67 * 67) / (650 * 650) = 3.33620355 (800 * 3.14 * 67 * 67) / (650 * 650) = 26.6896284
    15. 15. Performance evaluation <ul><li>Microscopic Analysis </li></ul><ul><ul><li>Optimality of the core </li></ul></ul><ul><ul><li>A-map overhead </li></ul></ul><ul><ul><li>Number of recovery events </li></ul></ul><ul><ul><li>Effect of random wireless errors </li></ul></ul>http://wshlab2.ee.kuas.edu.tw
    16. 16. Performance evaluation <ul><li>Evaluation of Variants </li></ul><ul><ul><li>Reliable Delivery within a Subregion </li></ul></ul>http://wshlab2.ee.kuas.edu.tw
    17. 17. Performance evaluation <ul><ul><li>Minimal Set of Sensors </li></ul></ul>http://wshlab2.ee.kuas.edu.tw
    18. 18. Conclusions <ul><li>Future work </li></ul><ul><ul><li>With mobility and in the presence of multiple sinks. </li></ul></ul><ul><li>We can do .. </li></ul><ul><ul><li>Take care of core ’s energy. </li></ul></ul><ul><ul><ul><li>By reelection </li></ul></ul></ul><ul><ul><li>Expand into multimedia </li></ul></ul><ul><ul><ul><li>Addition to multi processes. </li></ul></ul></ul><ul><ul><ul><li>How many duplicate does the environment have? </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    19. 19. Q & A Thank for your attention
    20. 20. Framework –D? <ul><li>Two-Phase Loss Recovery </li></ul><ul><ul><li>A-Map(Availability Map) </li></ul></ul><ul><ul><li>Function </li></ul></ul><ul><ul><ul><li>Loss detection </li></ul></ul></ul><ul><ul><ul><li>Loss recovery </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    21. 21. Performance evaluation <ul><li>Simulation Environment </li></ul><ul><ul><li>網路地形 </li></ul></ul><ul><ul><ul><li>100 node,650mx650m,randomly deployed </li></ul></ul></ul><ul><ul><ul><li>Sink in center </li></ul></ul></ul><ul><ul><ul><li>Range 67m </li></ul></ul></ul><ul><ul><ul><li>1Mbps </li></ul></ul></ul><ul><ul><ul><li>Message = 100 packets and 25 packets/per second (except for the single-packet-delivery part) </li></ul></ul></ul><ul><ul><ul><li>1 packet = 1Kbyte </li></ul></ul></ul><ul><ul><li>協定參數 </li></ul></ul><ul><ul><ul><li>MAC protocol : CSMA/CA </li></ul></ul></ul><ul><ul><ul><li>Routing : flooding </li></ul></ul></ul><ul><ul><ul><li>Simple : 20 randomly topologies </li></ul></ul></ul><ul><ul><ul><li>So 95% confidence intervals </li></ul></ul></ul><ul><ul><ul><li>Error model : 5% fixed packet loss rate </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    22. 22. Other reliability semantics <ul><li>Reliable Delivery within a Subregion </li></ul><ul><ul><ul><li>Without loss (100%) </li></ul></ul></ul><ul><ul><ul><li>First package decide the core. </li></ul></ul></ul><ul><ul><ul><li>Not choose itself? </li></ul></ul></ul><ul><ul><ul><ul><li>要怎麼決定成為 core? 透過什麼權值來證明它是好機器 ? </li></ul></ul></ul></ul><ul><li>Cover the Sensing Field </li></ul><ul><ul><ul><li>2R away from the nearest core node </li></ul></ul></ul><ul><ul><ul><ul><li>Ownership (defined by its transmission range) </li></ul></ul></ul></ul><ul><ul><ul><li>Core node can choose itself as a candidate </li></ul></ul></ul><ul><ul><ul><ul><li>結點少 , 自己判斷成為 core? </li></ul></ul></ul></ul><ul><li>Probabilistic Subset </li></ul><ul><ul><li>Scope sensing(ex:25%) </li></ul></ul><ul><ul><li>Triggers detected during the preliminary sensing </li></ul></ul><ul><ul><li>p% be candidate be core </li></ul></ul>http://wshlab2.ee.kuas.edu.tw <ul><ul><ul><li><- 是否使用在對某些興趣點做訂閱時使用 ? </li></ul></ul></ul>
    23. 23. <ul><ul><li>Environment considerations </li></ul></ul><ul><ul><ul><li>Scarcity of bandwidth and energy. </li></ul></ul></ul><ul><ul><li>Message considerations. </li></ul></ul><ul><ul><ul><li>The protocol to consider large-sized messages only before. but WSN need small-sized queries. </li></ul></ul></ul><ul><ul><ul><li>So issues on what kind of loss recovery. </li></ul></ul></ul><ul><ul><li>Reliability considerations </li></ul></ul><ul><ul><ul><li>100 percent reliable delivery to only a subregion. </li></ul></ul></ul>Introduction -D http://wshlab2.ee.kuas.edu.tw
    24. 24. Related work -D <ul><li>Before </li></ul><ul><ul><li>Efficient flooding </li></ul></ul><ul><ul><ul><li>Classify: probability-based, area-based and neighbor-knowledge-based </li></ul></ul></ul><ul><ul><ul><li>Can’t guarantee the reliability. </li></ul></ul></ul><ul><ul><li>“ Minimizing Broadcast Latency and Redundancy in Ad Hoc Networks” </li></ul></ul><ul><ul><ul><li>Broadcast tree and schedules transmissions. </li></ul></ul></ul><ul><ul><ul><li>Greedy strategy to minimize the latency and the number of retransmissions </li></ul></ul></ul><ul><ul><ul><li>Not suit large-scale networks </li></ul></ul></ul><ul><ul><li>Pump Slowly, Fetch Quickly (PSFQ) </li></ul></ul><ul><ul><ul><li>Relatively slow speed, using in-sequence forwarding. </li></ul></ul></ul><ul><ul><ul><li>Recover missing data packets from immediate neighbors. </li></ul></ul></ul><ul><ul><ul><li>Single-packet isn’t concider. </li></ul></ul></ul><ul><ul><li>TinyDB : Query processor </li></ul></ul><ul><ul><ul><li>Minimize power consumption </li></ul></ul></ul><ul><ul><ul><li>accuracy of query </li></ul></ul></ul><ul><ul><ul><li>No different services </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    25. 25. <ul><li>Challenges </li></ul><ul><li>Environment Constraints </li></ul><ul><ul><li>Not relying on statically constructed mechanism </li></ul></ul><ul><ul><ul><li>dynamics of the network </li></ul></ul></ul><ul><ul><li>Tremendous amount of spatial reuse. </li></ul></ul>Problem definition -D http://wshlab2.ee.kuas.edu.tw
    26. 26. Problem definition -D <ul><li>Acknowledgment (ACK)/NACK Paradox </li></ul><ul><ul><li>NACK </li></ul></ul><ul><ul><ul><li>Effective loss advertisement mechanism. </li></ul></ul></ul><ul><ul><ul><li>Low loss probabilities are not inordinately high.(The package is small) </li></ul></ul></ul><ul><ul><ul><li>Can‘t handle the unique case. When lost message at a part of node.(The middle node die) </li></ul></ul></ul><ul><ul><ul><li>Not aware, it cannot advertise a NACK to request retransmissions.(The aware message disappear.) </li></ul></ul></ul><ul><ul><li>ACK-based recovery </li></ul></ul><ul><ul><ul><li>Focus on all-packet-lost problem. </li></ul></ul></ul><ul><ul><ul><li>只能復原一個封包 ? 所以 WSN 會傳不到一個封包 ? 為了節省網路使用率 ? 還是能自救就自救 ? 這樣比較節省頻寬 </li></ul></ul></ul><ul><ul><ul><li>Deficiencies of ACK implosion (big overhead). ( 過度確認問題 ) </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    27. 27. Problem definition -D <ul><li>Reliability Semantics </li></ul>http://wshlab2.ee.kuas.edu.tw
    28. 28. GARUDA Design Element -D <ul><ul><ul><li>前言 </li></ul></ul></ul><ul><ul><ul><ul><li>機制 Two-phase loss recovery strategy that uses out-of-sequence forwarding </li></ul></ul></ul></ul><ul><ul><ul><ul><li>選舉系統 Simple candidacy-based approach for the core construction </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Improve NACK-based. </li></ul></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    29. 29. GARUDA Design Element -D <ul><ul><li>Instantaneous Core Construction </li></ul></ul><ul><ul><ul><li>First packet delivery to determine the hop_count </li></ul></ul></ul><ul><ul><ul><li>3i hop distance </li></ul></ul></ul><ul><ul><ul><li>Core lies </li></ul></ul></ul><ul><ul><ul><ul><li>Constructed using a single-packet flood </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Leveraged for more efficient and fair core construction. </li></ul></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    30. 30. GARUDA Design Element -D <ul><li>Multiple Reliability Semantics </li></ul><ul><ul><li>SPT(short path tree) can shortly delay. </li></ul></ul>http://wshlab2.ee.kuas.edu.tw 因為我沒探討其他信賴的題目
    31. 31. <ul><li>Loss Recovery Servers: Core </li></ul><ul><ul><li>Goal </li></ul></ul><ul><ul><ul><li>Minimize the retransmission overheads. </li></ul></ul></ul><ul><ul><ul><li>Constructed in a manner (the dynamic topology) </li></ul></ul></ul><ul><ul><li>Rationale of Core </li></ul></ul><ul><ul><ul><li>MDS(Minimum Domination Set) </li></ul></ul></ul><ul><ul><ul><li>MSC(Minimum Set Cover) </li></ul></ul></ul>Design Element http://wshlab2.ee.kuas.edu.tw <ul><ul><ul><ul><li>定義 MDS 以及 MSC 的問題 , 指出他們在這個模型中的腳色及相關性 </li></ul></ul></ul></ul>MDS
    32. 32. Design Element -D <ul><ul><li>A=PAPX(MDS) </li></ul></ul><ul><ul><li>B=OPT(MSC) </li></ul></ul><ul><ul><li>Cost = A/B </li></ul></ul><ul><ul><li>Classification </li></ul></ul><ul><ul><ul><li>Case 1 = optimal </li></ul></ul></ul><ul><ul><ul><li>Case 2 = worst case </li></ul></ul></ul><ul><ul><ul><li>Case 3 = half good or worst </li></ul></ul></ul><ul><ul><li>Sum up </li></ul></ul><ul><ul><ul><li>Replacing by approximation ratio </li></ul></ul></ul><ul><ul><ul><li>Using Approximation MDS </li></ul></ul></ul><ul><ul><ul><li>is what? </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw 重點 !! 詳細了解每個為什麼 建構的 cost G d :upper bound of the ratio
    33. 33. Design Element <ul><li>Loss Recovery Process </li></ul><ul><ul><li>Out-of-Sequence Packet Forwarding with </li></ul></ul><ul><ul><li>A-Map(Availability Map) </li></ul></ul><ul><ul><li>Two-Stage Loss Recovery </li></ul></ul><ul><ul><ul><li>Why does two-stage need? </li></ul></ul></ul><ul><ul><ul><ul><li>Avoid collide </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Single require </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Second recovery short than two hops </li></ul></ul></ul></ul><ul><ul><ul><li>Step </li></ul></ul></ul><ul><ul><ul><ul><li>Loss recovery for core nodes </li></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Uni-cast from upstream core </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><li>Loss recovery for noncore nodes </li></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Use the overhead – A-MAP, it’s basic flooding. </li></ul></ul></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    34. 34. Design Element <ul><li>Reliable Single-/First-Packet Delivery ? No relation </li></ul><ul><ul><li>Predict , 重傳 when the first-packet missed. ? </li></ul></ul><ul><ul><li>Benefits </li></ul></ul><ul><ul><ul><li>Robust fading effects ( 因為主動 ) </li></ul></ul></ul><ul><ul><ul><li>Robust to collision ( 沒人在聽的時候還是會尋找 ?) </li></ul></ul></ul><ul><ul><ul><li>Implicit NACK (suit in short package ) </li></ul></ul></ul><ul><ul><ul><li>Result in low energy </li></ul></ul></ul>http://wshlab2.ee.kuas.edu.tw
    35. 35. Implicit ACK http://wshlab2.ee.kuas.edu.tw 802.11 Implicit ACK Gain
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