Wireless Body Area Networks Overview

Wireless Body Area Networks (WBANs)

• Networks are essential for daily life, enabling communication between senders and receivers.
• WBANs are a significant advancement in network communication.
• Microelectromechanical systems (MEMS) and intelligent sensors allow for accurate body parameter predictions.
• WBANs are used in medical and non-medical applications.
• Real-time health monitoring is a core application, collecting physiological data in various environments.
• Low-power and energy-efficient design enables extended monitoring periods.
• Miniaturized sensors and wireless communication facilitate seamless data transfer to centralized systems.
• Artificial intelligence and machine learning enable personalized, context-aware health monitoring.

Introduction

• Current medical needs focus on physically challenged, elderly, and newborn populations.
• Chronic diseases like coronary heart, kidney, cerebrovascular diseases and several cancers are prevalent causes of death.
• Early detection can prevent mortality in the early stages.
• Advancements in healthcare demand innovative solutions for managing epidemics, endemics, pandemics, and financial crises.
• Real-time body data monitoring and storage in cloud-based medical records are crucial.
• Remote healthcare systems are becoming more common due to pandemics.

WBAN Architecture

• WBAN utilizes a three-tier architecture.
• Tier 1: Sensors embedded in the human body to collect data.
• Tier 2: Patient system transmits data to a central server.
• Tier 3: Medical server stores and processes data for medical professionals' use.

WBAN Topology

• WBAN primarily uses star topology.
• Each sensor node connects to a central sink node.
• One-hop topology connects each sensor directly to the sink.
• Two-hop topology connects some sensor nodes to each other and the sink. Choice depends on application needs.

IEEE 802 Layers

• IEEE 802 standards function at lower OSI levels concerning data link and physical layers.
• Logical Link Control (LLC) sublayer manages error detection.
• Medium Access Control (MAC) sublayer governs data transmission.
• MAC's distributed coordination function (DCF) employs Ethernet-based contention for resource allocation.
• MAC's point coordination function (PCF) provides contention-free access for high-priority traffic.

IEEE Standards

• WBAN utilizes IEEE 802.15.4 and 802.15.6 standards.
• IEEE 802.15.4 addresses physical and MAC layers for short-range, low-power, and lower bit-rate communication.
• IEEE 802.15.6 is for WBAN communication outside and inside the body.
• It enables short-range, low-power, and reliable communication.

WBAN Types

• Autonomous WBAN: Sensors make decisions and directly communicate with patients.
• Managed WBAN: Sensors send data to medical professionals, who interpret and act.
• Intelligent WBAN: Combines autonomous and managed approaches, addressing normal and emergency situations.

Network Classifications of WBANs

• WBANs classify traffic into on-demand (continuous or discontinuous), emergency, and regular or normal traffic.
• Emergency traffic is critical and unpredictable.
• Normal traffic happens in regular or patient-operated situations.

WBAN Sensor Types

• Implantable sensors: Invasive insertion, often for long-term use.
• Ingestible sensors: Ingested for passage through the gastrointestinal tract.
• Body-surfaced or patched sensors: Worn on the skin's surface for monitoring.

WBAN Traffic Classifications

• On-demand traffic: needed for critical events or when appropriate.
• Emergency traffic: used in emergency or critical situations where data transfer cannot be delayed.
• Normal traffic: used in normal situations.

WBAN Security

• Data Originality: Ensures data authenticity.
• Data Confidentiality: Data encryption is essential.
• Data Integrity: Checks for message alterations during transmission.
• Data Availability: Authorized access to data.
• Authentication: Verifies user identities to prevent unauthorized access.
• Authorization: Granting access based on user authentication.

WBAN Attacks

• Internal attacks within the network, often by malicious nodes.
• External attacks from outside the network using various methods.
• Passive attacks observe data without interfering.
• Active attacks tamper or modify data.

WBAN Authentication

• One-way authentication: Medical practitioner or patient sends credentials to verify identity.
• Mutual authentication: Both parties verify each other's credentials.
• Password-based authentication: Uses password for verification.
• Biometric authentication: Uses unique biological measurements for verification.
• Shared secret based: Uses pre-shared secrets.
• Asymmetric based: Uses public and private keys for verification.

WBAN Routing

• WBAN routing protocols address unique challenges of WBANs, including limited resources, mobility, and interference.
• Cluster-based protocols divide sensor nodes into clusters; each cluster has a cluster head and routes information to the sink.
• Cross-layered protocols utilize data from various layers to optimize routing decisions, considering energy, reliability and throughput.

WBAN MAC Protocols

• Collision-free protocols (scheduling-based, polling-based) use predefined time slots or polling processes to avoid collisions.
• Contention-based protocols (CSMA/CA) allow nodes to contend for access to the channel, adapting to changes in data traffic.
• Hybrid protocols combine elements from both collision-free and contention-based approaches.

WBAN Research Issues

• Raw material requirements for sensor manufacturing.
• Data link layer design for improving stability and efficiency.
• Continuous sensor operation in high-demand environments.
• Signal loss mitigation due to anatomical and environmental factors.

WBAN Applications

• Medical Applications: Seizure detection, soldier health monitoring, cardiovascular monitoring, cancer detection.
• Non-Medical Applications: Entertainment, disaster management, tele-healthcare.

WBAN Advancements

• Quantum cryptography for enhanced security.
• Virtual Reality (VR) integration for enhanced patient care.
• Artificial intelligence (AI) for automatic medical assistance.
• Energy harvesting for long-term operation of WBAN devices.