The slide introduces the topic of hierarchical routing protocols in wireless sensor networks. It specifically focuses on the PEGASIS protocol, emphasizing its role in enhancing energy efficiency within WSNs.

Hierarchical Routing Protocols in Wireless Sensor Networks

Focusing on the PEGASIS Protocol for Energy Efficiency in WSN

Wireless Sensor Networks (WSN) consist of distributed sensor nodes that collect and transmit environmental data wirelessly to a base station via communication infrastructure. They enable real-time applications like monitoring temperature, humidity, and pollution, but face challenges from limited battery life requiring power-efficient routing protocols.

Introduction to Wireless Sensor Networks (WSN)

• Definition: Distributed sensors collecting and transmitting environmental data wirelessly
• Components: Sensor nodes, base station, and communication infrastructure
• Applications: Monitoring temperature, humidity, and pollution in real-time environments
• Energy Constraints: Limited battery life demands power-efficient routing protocols

Hierarchical routing organizes sensor nodes into clusters with designated cluster heads acting as coordinators to enable efficient communication and data aggregation at intermediate levels. This multi-level approach minimizes energy consumption and optimizes routing paths in resource-constrained wireless sensor networks.

Hierarchical Routing Concepts

• Organizes sensor nodes into clusters for efficient communication
• Designates cluster heads as role-based coordinators
• Implements multi-level hierarchy to minimize energy use
• Enables data aggregation at intermediate levels
• Optimizes routing paths in resource-constrained WSNs

Flat routing in wireless sensor networks (WSNs) suffers from issues like excessive flooding for route discovery, causing network congestion, high collisions, and rapid energy drain due to equal participation by all nodes. In contrast, hierarchical routing addresses these by clustering nodes under leaders, enabling scalability, efficient data aggregation to cut redundancies, lower energy consumption, and extended network lifetime in resource-limited environments.

Advantages Over Flat Routing

PEGASIS forms a chain-based virtual backbone that connects all sensor nodes, enabling efficient local data transmission to minimize energy consumption. A selected leader node aggregates data from the chain, fuses it, and transmits the result to the base station.

PEGASIS: Power-Efficient Gathering in Sensor Information Systems

• Forms chain-based virtual backbone connecting all sensor nodes.
• Selects leader node for data aggregation from chain.
• Leader fuses data and transmits to base station.
• Minimizes energy use by local data transmission.

The PEGASIS algorithm begins by constructing a linear chain of sensor nodes using a greedy method to minimize energy use in data transmission, followed by selecting an initial leader node to aggregate data from the chain and send it to the base station. Data is then relayed sequentially along the chain to the leader, with the leadership role rotating periodically among nodes to balance energy consumption and prolong network lifetime.

Algorithmic Steps of PEGASIS

Step 1: Construct Chain via Greedy Algorithm Nodes form a linear chain using a greedy method to optimize distance and reduce energy dissipation during data transmission. Step 2: Select Initial Leader Node A leader is chosen from the chain to aggregate data from all nodes and transmit to the base station. Step 3: Relay Data Along Chain Sensor nodes pass data sequentially along the chain to the leader for aggregation and forwarding. Step 4: Rotate Leader Role Periodically The leader position rotates among nodes in subsequent rounds to balance energy load and extend network lifetime.

The slide compares the PEGASIS protocol to LEACH, highlighting a 30-50% reduction in energy use and a 40% extension in network lifetime for PEGASIS. These performance improvements are validated through simulation results that emphasize key metrics.

Performance Comparison with LEACH

• 30-50%: Energy Use Reduction

PEGASIS vs LEACH protocol

• 40%: Network Lifetime Extension

Longer life than LEACH

• Simulation: Validated Results

Highlighted performance metrics

PEGASIS offers key advantages by reducing overall energy dissipation in the network and eliminating the overhead associated with cluster formation processes. It also provides fault tolerance for robust operation while extending the network lifetime beyond traditional methods.

Advantages of PEGASIS

• Reduces overall energy dissipation in the network
• Eliminates overhead from cluster formation processes
• Provides fault tolerance for robust operation
• Extends network lifetime beyond traditional methods

PEGASIS faces limitations such as high latency from its long chain structures and a single point of failure at the leader node. Additionally, it struggles with scalability in large networks and assumes a uniform distribution of nodes.

Limitations of PEGASIS

• High latency due to long chain structures
• Single point of failure at leader node
• Scalability issues in large networks
• Assumes uniform node distribution

PEGASIS improves wireless sensor network efficiency through chain-based data gathering, with future work focusing on hybrid protocols for better performance. Key takeaways highlight how hierarchical routing cuts energy use, boosts scalability, and extends network lifetime, followed by an invitation for questions on WSN routing advancements.

Conclusion

PEGASIS enhances WSN efficiency via chain-based gathering.

Future Work: Explore hybrid protocols for optimized performance.

Key Takeaways:

• Hierarchical routing reduces energy consumption.
• Improves scalability and network lifetime.

Thank you for your attention.

Questions? Let's discuss advancements in WSN routing.

Source: Hierarchical Routing Protocols in WSN: Focus on PEGASIS