1 / 18

Real-Time Communication Architecture for Wireless Sensor Networks

Explore RAP, a real-time communication architecture for large wireless sensor networks, optimizing packet deadlines, scalability, and efficiency. Learn about query/event services, location-based addressing, geographic forwarding, scheduling strategies, and MAC layer prioritization.

lzarate
Download Presentation

Real-Time Communication Architecture for Wireless Sensor Networks

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A Real-Time Communication Architecturefor Wireless Sensor Networks Neil Tang4/22/2009 CS541 Advanced Networking

  2. Please complete the online course survey at: www.cs.montana.edu/survey 2 CS541 Advanced Networking CS541 Advanced Networking

  3. Outline Reference System Model Design Goals RAP Simulation Results 3 CS541 Advanced Networking CS541 Advanced Networking

  4. Reference • C. Lu, B. Blum, T. F. Abdelzaher, J. A Stankovic and T. He, RAP: a real-time communication architecture for large size wireless sensor networks IEEE RTAS’2002, pp. 55-66. CS541 Advanced Networking

  5. System Model • Large scale and high density network • Very limited energy • Queries are usually associated with timing requirements • Data aggregation • Multihop communication • Addressing based on locations • Congestion in “hot regions” CS541 Advanced Networking

  6. Design Goals • Provide general service APIs. • Maximize the number of packets meeting their end-to-end deadlines. • Scale well with a large number of nodes and hops. • Introduce minimum communication and processing overhead. CS541 Advanced Networking

  7. RAP Architecture CS541 Advanced Networking

  8. Query/Event Service API • query(attribute_list, area, timing_constraints, querier_loc) • register_event(event, area, query) CS541 Advanced Networking

  9. Location-Addressed Protocol • Similar to UDP except that messages are addressed by location instead of IP address. • Support three kinds of communications: unicast, area multicast and area anycast. CS541 Advanced Networking

  10. Geographic Forwarding (GF) • GF makes a greedy decision to forward a packet to a neighbor if 1) it has the shortest geographic distance to the packet’s destination among all immediate neighbors; and 2) it is closer to the destination than the forwarding node. • When such nodes do not exist, the GPSR protocol [16] can be used to route packets around the perimeter of the void region. CS541 Advanced Networking

  11. Velocity Monotonic Scheduling • Deadline-aware • Distance-aware CS541 Advanced Networking

  12. Velocity Monotonic Scheduling • Static Velocity Monotonic: • Dynamic Velocity Monotonic: • No synchronization is needed to determine the elapsed time. CS541 Advanced Networking

  13. Priority Queue • Single FCFS Queue: Packets need to be inserted in the order of their priorities. • Multiple FIFO Queues: Each queue corresponds to a fixed priority level. Each priority level corresponds to a range of requested velocities. • Time complexities? CS541 Advanced Networking

  14. MAC Layer Prioritization • Enhanced 802.11 DCF (EDCF) • DIFS: DIFS = BASE_DIFS * PRIORITY • Backoff increase function: CW=CW*(2+(PRIORITY-1)/MAX_PRIORITY) CS541 Advanced Networking

  15. Summary • RAP provides general query and event service APIs. • RAP increases the number of packets meeting their end-to-end deadlines by prioritizing the transmission of contending packets based on their requested velocities. • RAP scales well in large-scale sensor networks since every algorithm/protocol only needs local information. CS541 Advanced Networking

  16. Simulation Settings • Radio transmission range: 30.5m • Packet size: 32-160B • Link bandwidth: 200kbps CS541 Advanced Networking

  17. Simulation Results CS541 Advanced Networking

  18. Simulation Results CS541 Advanced Networking

More Related