DDMAC: Dynamic Delayed Medium Access Control (MAC) Protocol with Fuzzy Technique for Wireless Body Area Network By: Ido Polak Netanel Ring

Introduction Motivation Fuzzy Logic IEEE MAC Protocol MAC with fuzzy Summary Outline

Traffic of the WBAN is diverse due to different monitoring tasks carried on by sensor nodes. Difficulty in how to efficiently organize the access to the medium of the dynamic and various generated traffic. Introduction

Fuzzy logic system is used to make the backoff time produced in IEEE MAC protocol adaptive. Improving reliability in packet transmissions. Decrease in the latency. Introduction

Different Data rate ranges for different application. Data rate and number of nodes in the network cannot be considered tunable Motivation

Definition of fuzzy — “not clear, distinct, or precise; blurred” Definition of fuzzy logic —A form of knowledge representation suitable for notions that cannot be defined precisely, but which depend upon their contexts. What is Fuzzy Logic?

Definition of linguistic variable While variables in mathematics usually take numerical values, in fuzzy logic applications, the non-numeric are often used to facilitate the expression of rules and facts. What is Fuzzy Logic?

A linguistic variable such as speed may have a value such as fast or its antonym slow. What is Fuzzy Logic?

For every problem must represent in terms of fuzzy sets. Fuzzy set is a pair (U, m) where U is a set and m:U ->[0.1] What is Fuzzy Logic?

not included fully included fuzzy member What is Fuzzy Logic?

Rules are usually expressed in the form: IF temperature IS cold THEN turn down fan IF temperature IS hot THEN speed up fan NOT x = (1 - truth(x)) x AND y = minimum(truth(x), truth(y)) x OR y = maximum(truth(x), truth(y)) What is Fuzzy Logic?

Specifies physical and MAC for LR-WPAN. Low cost communication of near by devices. Important features: o Real-Time. o Collision Avoidance (CSMA/CA). o Security (optional). IEEE

Important for wireless networks. Carrier Sense. Collision Avoidance. o Request to send/Clear to send. o Transmission. CSMA/CA

Two clear channel assessments (CCA) before any packet transmission. if not o generate a backoff delay  random(0,2^BE -1) else o execute the transmission CSMA/CA

Maintain three variables: o NB (number backoffs). o BE (backoff exponent). o CW (contention window). CSMA/CA

Limit the randomly produced backoff time with FuzzyMaxDelay. The difference in the algorithms: o rnd(0,2^BE -1) o rnd(0,FuzzyMaxDelay) DDMAC Implementation

FuzzyMaxDelay is based on: o data rate. o channel clear rate. DDMAC Implementation

Fuzzy Inputs and Output

DDMAC Implementation Fuzzy Inputs and Output

DDMAC Implementation Fuzzy Inference System

Dynamic adaptive approach on top of IEEE MAC mechanism. Consider traffic characteristics: o node’s data rate. o history of successful channel access. Summary

Use these two inputs in a fuzzy inference system to generate a dynamic bound for the backoff window. Build a fair access among nodes of a WBAN to improve: o Overall latency. o reliability. Summary