Presented by: Dr. Khaled A. Ali Urgency-based MAC Protocol for WSBANs WiSense Seminar Series

Introduction Wireless Personal Area Networks WSBAN Application Examples IEEE MAC Protocol Urgency-based MAC Protocol for WSBANs U-MAC Performance Evaluation and Results Concluding Remarks Outline

Massive deployment of Sensor Networks –Stimulated by numerous industry segments, and government organizations –Sensors and RFID tags will begin to inhabit every object –Emergence of smart sensors with local intelligence Traffic volume increases dramatically –Significant architectural changes to global IT infrastructure is expected –Process moves to network edge to aggregate and filter traffic –Directional shift in network traffic Introduction

Integration of WSNs into 4G Networks –Evolution of current ITU and IEEE standards –Connect sensor world with back-end computing environments –Enable end-to-end solutions –Mixed Network Traffic of different priority levels and different bandwidth requirements Introduction IP Network 4G network Sensor Net 2G network 3G network Phone network Other networks Cellular Net

WPAN (General Description): –Low-rate: (250 kb/s, 40 kb/s and 20 kb/s data rates) –Range: meters –Low power consumption –Addresses: short 16-bit or long 64-bit –Channels: 16 channels (2450 MHz band), 10 channels (915 MHz band ) and 1 channel (868 MHz band) –Access mechanisms: CSMA/CA or Aloha –Reliability : Fully acknowledgement, error checking –Cost: Low cost of deployment –MAC& PHY: IEEE and IEEE a Wireless Personal Area Networks

WPAN (Network Topology): Wireless Personal Area Networks FFD (PAN)RFD star topology peer-to-peer topology

WPAN (Layered Architecture): Wireless Personal Area Networks Upper Layers MAC PHY Physical Medium SSCS LLC

Non-invasive WSBANs: –Monitoring and sensing signals from the human body for medical applications –Distributed communication over the human body Invasive (In-Body) WSBANs: –Connect implanted medical devices (MICS band) and on-body sensors (ISM band) –Miniature “Pill camera” Images and medical data are transmitted to a central WS View, edit, archive and the live video, images and date Physician can observe and detect exact location of suspected “in-body” disorder Patient data can be sent through the network to establish a diagnosis and trigger the required actions via actuators WSBAN Application Example Personal Health Care-mixed data rates

RFID tag integrated in the watch allows entrance in the conference room Presentation can be downloaded from nodes in the room Business cards are exchanged by handshake Additional information can be displayed by video glasses Using microphone/motion sensors the main processing unit becomes aware of the meeting and automatically blocks phone calls WSBAN Application Example Business Meeting-mixed data rates

MAC Sublayer –Generating Network beacons (PAN) –Synchronization –PAN association and disassociation –CSMA-CA –GTS IEEE MAC Protocol INACTIVE Beacon CFP(GTS)CAP CAP- Contention Access Period CFP- Contention Free Period GTS- Guaranteed Time Slots

Objectives: –Supporting QoS in WSBANs for medical applications –Increasing network throughput –Minimizing packet rejection rate –Minimizing power consumption Approach: –Star network topology –Controlling the number of packet retransmission High priority traffic contend more for the transmission medium than low priority traffic –Slotted Aloha access mechanism Urgency-based MAC Protocol for WSBANs

Traffic Classification –Critical Traffic –Non-Critical Traffic Arrival Rate –New Packet Arrival rate (λ) Critical packet arrival rate Non critical packet arrival rate –Retransmitted packet arrival rate (λ r ) Retransmission Queues Urgency-based MAC Protocol for WSBANs U-MAC Block diagram C1C1 C2C2 C3C3 CrCr λ λ + λ r Channel Success Collision

Packet Transmission Scenario: –Number of critical packet retransmission s; r c = 3 –Number of non critical packet retransmissions ;r nc = 2 Urgency-based MAC Protocol for WSBANs PcPc P nc 32 rcrc r nc 21 10

Beacon frame enabled Star network topology RFD nodes communicate with a single FFD RFD nodes composed of critical nodes and non critical nodes Critical nodes contend for the medium r c times Non critical nodes contend for the medium r nc times U-MAC Performance Evaluation and Results Maximum number of Critical Nodes Critical Nodes Packet Arrival Rate Network Throughput

Maximum Number of Critical Nodes N c –Aggrigate Packet Arrival rate G=1 –Number of Critical Nodes U-MAC Performance Evaluation and Results

Maximum Number of Critical Nodes N c (Cont.) –N total =20 G=1 –λ c =0.05, 0.06 –λ nc =0.015 –r nc = 0, 2, 5 –r c = 0- 5 U-MAC Performance Evaluation and Results

Critical Packet Arrival Rate –N total =20, N c =5 G=1 –λ nc =0.015 –r nc = 0, 2, 5 –r c = 0- 5 U-MAC Performance Evaluation and Results

Network Throughput –Critical Nodes Throughput –Non Critical Nodes Throughput U-MAC Performance Evaluation and Results

Network Throughput (Cont.) –N c =10 N nc =10 r nc = time slots each of 1 sec. U-MAC Performance Evaluation and Results λ c =λ nc =0.025 λ c =λ nc =0.03

An Urgency-Based MAC protocol for WSBAN is proposed U-MAC protocol differentiates nodal medium access based of the criticality of the reported traffic Critical traffic is allowed to retransmit collided packets more than non critical traffic U-MAC protocol performance is evaluated mathematically and through simulation The performance results show the ability of the proposed protocol to differentiate network traffic Concluding Remarks

Thank you