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PhD. Thesis defence Slides

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PhD. Thesis defence Slides

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PhD. Thesis defence Slides

  1. 1. 104th PhD thesis defense at PPGEE/UFPA Cross-layer Optimizations for Multimedia Distribution over WMSNs and FANETs with QoE Support Denis Lima do Rosário Advisors: Eduardo Coelho Cerqueira Torsten Braun
  2. 2. Outline ´ Introduction ´ Multi-hop and multi-path hierarchical routing protocol for Efficient VIdeo transmission (MEVI) ´ Cross-layer Link quality and Geographical-aware beaconless Opportunistic routing protocol (XLinGO) ´ Conclusion and Future Work 2
  3. 3. Introduction – Wireless Multimedia Sensor Network (WMSN) Scenario 3
  4. 4. Introduction – Flying Ad-hoc Network (FANET) Scenario Systems Mobile UsersBase Station Control Center 4
  5. 5. Requirements for a Real-time Multimedia Distribution I ´ Scalability ´ Routing protocols must provide an efficient multi-hop communication between any pair of source and destination nodes, in order to deliver the collected data from any part of the monitored area. ´ The multi-hop communication must be scalable without requiring user intervention, and also independently of the number of nodes or field size ´ Efficient Buffer Control ´ Multimedia dissemination usually involves a set of nodes transmitting multiple video flows simultaneously. ´ Leading to a higher degree of network congestion, buffer overflow, and packet loss ratio, which reduces the quality level of the delivered video flows. ´ The routing protocol must prevent the selection of forwarding nodes with heavy traffic load. 5
  6. 6. Requirements for a Real-time Multimedia Distribution II ´ Robustness ´ The network nodes must cope with dynamic topologies caused by node failure or mobility, and wireless channel changes ´ The multimedia dissemination continue reliable and robust despite dynamic topologies. ´ Energy-efficiency ´ Energy consumption is also prime concern in WMSNs and FANETs ´ Both networks consist of battery-powered nodes with limited energy resources. ´ The development of energy-efficient communication protocols is one of the main goals to increase network lifetime. 6
  7. 7. Requirements for a Real-time Multimedia Distribution III ´ Quality of Experience (QoE) Requirements ´ Solutions involving multimedia transmissions must evaluate the video content from the user’s perspective and not only from the network’s perspective. ´ Over the last decade the focus has shifted away from pure network point-of-view assessment (QoS metrics) to a more human-centric approach (QoE metrics) and user-awareness. ´ QoS schemes alone are not enough to assess the quality level of multimedia applications, because they fail to capture subjective aspects of video content related to human experience and subjectivity 7
  8. 8. Requirements for a Real-time Multimedia Distribution IV ´ Unreliable Nature of Wireless Channels ´ Link quality estimation is a fundamental building block in the design of routing protocols for WMSN and multimedia FANET scenarios ´ A reliable routing protocol must consider the link quality as a metric to select reliable quality routes for multimedia dissemination. 8
  9. 9. Main Research Question and Contributions ´  The main research contributions of this thesis addresses by the research question of how to provide real-time multimedia distribution with high energy-efficiency, reliability, robustness, scalability, and QoE support over wireless ad-hoc networks. ´  Multi-hop and multi-path hierarchical routing protocol for Efficient VIdeo transmission for static WMSN scenarios (MEVI) ´  Cross-layer Link quality and Geographical-aware beaconless OR protocol for multimedia FANET scenarios (XLinGO) ´  QoE-aware Packet-Level Redundancy Mechanism (QoE-aware redundancy) ´  Mobile MultiMedia Wireless Sensor Network (M3WSN) OMNeT++ framework 9
  10. 10. Thesis Contributions Source Node Destination NodeIntermediate Node Physical Application Transport MAC Routing Wireless ad-hoc network Physical MAC Routing Physical Application Transport MAC RoutingXLinGO or MEVIXLinGO or MEVI QoE-aware redundancy 10
  11. 11. Related Work ´ The existing hierarchical routing protocols have the following drawbacks: ´ Include a higher overhead to create cluster. ´ Lack of efficient multi-hop and multi-path communication. ´ Lack of reliable cross-layer approach to select routes based on information about. ´ End-to-end link quality estimation; ´ Energy; ´ Number of Hops. ´ The existing beaconless OR protocols have the following drawbacks: ´ Do not consider multiple metrics for forwarding decisions. ´ Do not quickly detecting and responding to topology changes. 11
  12. 12. Outline ´ Introduction ´ MEVI ´ Design and Operation Principles ´ Simulation Environment and Metrics ´ Evaluation ´ XLinGO ´ Conclusion and Future Work 12
  13. 13. Multi-hop and multi-path hierarchical routing protocol for Efficient VIdeo transmission (MEVI) ´ MEVI is designed to work in a WMSN application with a fixed network infrastructure to accurately monitor physical scalar measurements, and also collect multimedia data in the case of an event occurrence. ´ MEVI relies on: ´ Hierarchical architecture; ´ Heterogeneous nodes; ´ MEVI considers two phases for data transmission: ´ Intra-cluster communication; ´ Inter-cluster communication. 13
  14. 14. MEVI: Intra-Cluster Communication ´ Network nodes create clusters. ´ Cluster members sending the sensed value in a specific slot to their Cluster Head (CH). ´ Clusters are created with low signaling overhead, since nodes only send: ´ Beacons; ´ Data. 14
  15. 15. MEVI: Inter-Cluster Communication MEVI exploits a reactive scheme to find on-demand multiple paths. •  Route request; and •  Route reply messages. Each possible path has a Path Quality (PQ) associated. •  E n d - t o - e n d l i n k q u a l i t y estimation; •  Energy; •  Number of Hops. 15
  16. 16. MEVI: Inter-Cluster Communication CHs must send the aggregate packet to the DN. 16
  17. 17. MEVI: Inter-Cluster Communication DN must analyze the received data by means of existing models or methods. It requests a video sequence from a given CH, as soon as it detects an event occurrence. 17
  18. 18. MEVI: Inter-Cluster Communication M E V I s c h e d u l e s p a c k e t transmissions via multiple paths to provide robustness and load balancing. MEVI schedules the transmission of priority frames via the best path •  I-frame; and •  first P-frames. 18
  19. 19. Outline ´ Introduction ´ MEVI ´ Design and Operation Principles ´ Simulation Environment and Metrics ´ Evaluation ´ XLinGO ´ Conclusion and Future Work 19
  20. 20. Mobile MultiMedia Wireless Sensor Network OMNeT++ framework (M3WSN) ´ M3WSN framework relies on Castalia architecture to provide new functionalities. ´ It implements full support to: ´ deliver, control, and evaluating real video sequences. ´ scenarios composed of fixed and mobile nodes, as well as moving object. 20
  21. 21. Evaluation Metrics ´ Energy-Efficiency Evaluation ´ Network lifetime ´ time spent until 10% of the network nodes remain alive; or ´ the moment of the first node run out of energy resources. ´ Objective and Subjective QoE Evaluation ´ Structural SIMilarity (SSIM) measures the structural distortion of the video, and attempts to obtain a better correlation with the user’s subjective impression. ´ Transmitted frame 21
  22. 22. Outline ´ Introduction ´ MEVI ´ Design and Operation Principles ´ Simulation Environment and Metrics ´ Evaluation ´ XLinGO ´ Conclusion and Future Work 22
  23. 23. Evaluation Goal ´ Simulation experiments aim to show the scalability, reliability, and energy-efficiency of MEVI for transmitting multimedia content compared to existing hierarchical routing protocols for a static WMSN scenarios. 23
  24. 24. Hierarchical Routing Protocols under Evaluation ´  MEVI ´  Nodes create clusters with low overhead. ´  Nodes classify routes based on multiple metrics. ´  It considers a multi-path video transmission ´  LEACH ´  Nodes have homogeneous capabilities and transmit beacon, join, and schedule messages for cluster formation. ´  LEACH fixed CHs ´  Nodes have heterogeneous capabilities, i.e., it considers fixed CHs. ´  It follows the traditional LEACH implementation for cluster formation. ´  PEMuR: ´  nodes periodically create clusters in a centralized way by transmitting beacon, schedule, advertisement, identifier, and also join messages. ´  Nodes classify routes based only on remaining energy. 24
  25. 25. Network Lifetime LEACH fixed CHs 25
  26. 26. Video Quality MEVIPEMuR LEACH LEACH fixed CHs 26
  27. 27. Original MEVI LEACH PEMuR 27 Frame of transmitted video27
  28. 28. MEVI in Summary ´ It considers a cluster formation with low overhead. ´ provides efficient and reliable intra-cluster communication. ´ It triggers the multimedia transmission according to the sensed value. ´ avoids the transmission of unnecessary video content and saving scarce network resources, such as energy and bandwidth. ´ It finds a subset of reliable CHs to establish multiple paths. ´ the subset of optimal CHs must provide high packet delivery rate. ´ It schedules multimedia transmission via multi-paths according to the frame relevance ´ provides load balancing, robustness, and QoE-awareness. 28
  29. 29. Outline ´ Introduction ´ MEVI ´ XLinGO ´ Design and Operation Principles ´ Evaluation ´ Conclusion and Future Work 29
  30. 30. Cross-layer Link quality and Geographical- aware beaconless OR protocol (XLinGO) ´  XLinGO is designed to work in multimedia FANET application to explore, sense, and also send multimedia data from the hazardous area as soon as the fixed network infrastructure is not available. ´  The main goal is to deliver multimedia content with a minimum video quality level from user’s perspective. ´  XlinGO relies on a beaconless OR approach ´  Takes into account multiple metrics for forwarding decision. ´  Considers a recovery mechanism for route reconstruction. ´  Includes two operational modes: ´  Contention-based forwarding mode; ´  Persistent route mode. 30
  31. 31. Opportunistic Routing - coordination method ´ Beacon-based OR ´ Selects and prioritizes a set of candidate nodes by transmitting beacon messages before packet transmission. ´ Creates and orders a relay candidate list prior to packet transmission according to a certain criteria, such as expected transmission count. ´ Determines the candidate list before sending packets, and may not reflect the real situation at the moment of packet transmission. ´ Beaconless OR ´ Forwarding decisions are performed by the receiver of a packet. ´ Adds a small Dynamic Forwarding Delay (DFD) value before packet transmission. ´ Candidate node with best conditions compute the shortest DFD value, and thus such node transmits the packet faster. 31
  32. 32. XLinGO: Contention-based forwarding mode 32
  33. 33. XLinGO: Contention-based forwarding mode 1.  Source broadcasts the video packet 33
  34. 34. XLinGO: Contention-based forwarding mode 1.  Source broadcasts the video packet 2.  Nodes analyze the forwarding area 34
  35. 35. XLinGO: Contention-based forwarding mode 1.  Source broadcasts the video packet 2.  Nodes analyze the forwarding area 3.  Nodes inside PPA compute the DFD based on geographical information, queue size, energy, and link quality. 35
  36. 36. XLinGO: Contention-based forwarding mode 1.  Source broadcasts the video packet 2.  Nodes analyze the forwarding area 3.  Nodes inside PPA compute the DFD based on geographical information, queue size, energy, and link quality 4.  Node that generates the smallest DFD forwards the packet faster 36
  37. 37. XLinGO: Contention-based forwarding mode 37
  38. 38. XLinGO: Persistent forwarding mode SN Fi Data packets … 1.  SN sends n video packet to Fi 2.  Fi computes the average of link quality and PDR for the last n received packets 3.  Fi sends a reply message to SN and piggyback link quality and PDR 4.  SN evaluates if it continues transmitting packets to Fi or if it returns to the Contention-based forwarding mode 38
  39. 39. Outline ´ Introduction ´ MEVI ´ XLinGO ´ Design and Operation Principles ´ Evaluation ´ Conclusion and Future Work 39
  40. 40. Evaluation Metrics and Goal ´ Simulation experiments aim ´ to show the performance of the recovery mechanism to quickly detect and react to topology changes. ´ to evaluate different beaconless OR protocol in a scenario with node mobility and simultaneous multiple video flows dissemination. ´ Objective and Subjective QoE Evaluation ´ Structural SIMilarity (SSIM) measures the structural distortion of the video, and attempts to obtain a better correlation with the user’s subjective impression. ´ Transmitted video. 40
  41. 41. Beaconless OR Protocols under Evaluation ´ Original video ´ represents an errorless video transmission. ´ XLinGO ´ does not have node failures and recovery mechanism;. ´ XLinGO – Failure ´ relies on periodic route reconstruction. ´ experiences node failures. ´ XLinGO – Recovery ´ considers the recovery mechanism and experiences node failures. 41
  42. 42. Impact of the mechanism to recover from route failures Interval for route reconstruction Timeout to detect route failure 42
  43. 43. Beaconless OR Protocols under Evaluation ´  XLinGO ´  combines queue length, link quality, geographical location, and residual energy to compute the DFD. ´  relies on a recovery mechanism to react faster to route failure situations. ´  LinGO ´  combines link quality, geographical information, and energy to compute the DFD. ´  relies on periodic route reconstruction. ´  BLR ´  considers only geographical information to compute the DFD. ´  relies on periodic route reconstruction. ´  BOSS ´  relies only on geographical information to compute the DFD. ´  consider a tree-way handshake. ´  relies on periodic route reconstruction. ´  MRR ´  compute the DFD function based on geographical information, RSSI, and energy. ´  relies on a periodic route reconstruction. 43
  44. 44. Simulation Description ´ Field size of 100x100 ´ Deployed 40 nodes ´ 1 – Destination node (static) ´ 2 – Mobile source nodes ´ 38 – Mobile possible forwarder nodes ´ Transmitted videos ´ Container, Hall, and Highway (YUV library) ´ UAV1 and UAV2 (downloaded from Youtube) 44
  45. 45. Impact of Node Mobility45
  46. 46. Transmitted video Video Transmitted via XLinGO Video Transmitted via BLR More videos at: https://plus.google.com/b/102508553201652207043/102508553201652207043/posts 46
  47. 47. XLinGO in Summary ´ It finds a subset of reliable forwarders to establish a persistent route ´ the subset of optimal forwarders provides high packet delivery rate, enabling video delivery with high video quality level from the user’s experience. ´ It prevents the selection of a forwarders with heavy traffic load or low residual energy. ´ providing load balancing and energy-efficiency, as well as reduce queue congestions, packet loss, delay, and jitter. ´ It determines whether one of the forwarders from a given persistent route might be no longer available or still reliable to forward packets. ´ enabling a smoother operation in mobile networks. ´ providing robust and reliable multimedia transmission. 47
  48. 48. Outline ´ Introduction ´ MEVI ´ XLinGO ´ Conclusion and Future Work 48
  49. 49. Conclusion ´  We addressed the main research question of this thesis ´  how to provide real-time multimedia distribution with high energy-efficiency, reliability, robustness, scalability, and QoE support over wireless ad-hoc networks. ´  We developed: ´  Multi-hop and multi-path hierarchical routing protocol for Efficient VIdeo transmission for static WMSN scenarios (MEVI) ´  Cross-layer Link quality and Geographical-aware beaconless OR protocol for multimedia FANET scenarios (XLinGO) ´  QoE-aware Packet-Level Redundancy Mechanism (QoE-aware redundancy) ´  Mobile MultiMedia Wireless Sensor Network (M3WSN) OMNeT++ framework ´  We consider two classes of applications. ´  WMSN application that relies on fixed network infrastructure to accurately monitor physical scalar measurements, and also collect multimedia data in the case of an event occurrence. ´  Multimedia FANET application to explore, sense, and also send multimedia data from the hazardous area as soon as the fixed network infrastructure is not available. 49
  50. 50. Conclusion Source Node Destination NodeIntermediate Node Physical Application Transport MAC Routing Wireless ad-hoc network Physical MAC Routing Physical Application Transport MAC Routing MEVI and XLinGO MEVI and XLinGO QoE-aware redundancy ´ We address several problem domains with contributions on different layers of the communication stack. 50
  51. 51. Conclusion ´ The performance and behavior of our contribution for multimedia distribution was evaluated by means of simulation experiments. ´ Based on simulation results, we conclude that our cross-layer optimizations for multimedia distribution over WMSN and multimedia FANETs achieved results that filled the goal of our initial research question. *All developed modules will be available at http://cds.unibe.ch/research/M3WSN/ 51
  52. 52. Future works ´ Perform Testbed experiments and long-term real- world deployment to confirm the simulation results. ´ TARWIS ´ XLinGO must consider the link expiration time estimation, position prediction, and moving direction in a 3D plane for routing decision. ´ avoiding the selection of a forwarder node that is moving in opposite direction in a 3D plane than its previous hop, which avoids loops and prevents suboptimal routing. 52
  53. 53. Future works ´ Several issues need to be studied and understood in order to extend MEVI and XLinGO by taking into consideration, such as human-centric schemes, video characteristics, and context- awareness for decision making. ´ online QoE assessment and user experience can be measured and integrated into MEVI and XLinGO protocols, in order to support routing decisions to improve the user satisfaction on watching real-time video flows. 53
  54. 54. List of Publications in Summary ´ 20 publications in national or international refereed journals, conferences, or workshops ´ 2 - Qualis A1 (2 journals) ´ 2 - Qualis A2 (1 journal and 1 conference) ´ 1 - Qualis B1 (1 conference) ´ 1 - Qualis B2 (1 conference) ´ 2 - Qualis B3 (2 conferences) ´ 2 - Qualis B4 (2 conferences) ´ 1 - Qualis B5 (1 journal) ´ 2 - Book Chapters ´ 7 - Qualis not Available *Following the ENG IV Qualis for journals papers, and CC Qualis for conference papers 54

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