| | Layer | Issues | References |
| | Physical layer | Frequency selection/carrier frequency generation, data encryption, modulation and demodulation, channel coding/modelling, signal detection, antenna sensitivity and transceiver design, wave propagation, spread spectrum communication, packet transmission and synchronization, channel coding, multiplexing/demultiplexing | [40, 41] |
| | Link/MAC layer | Hidden node problem, congestion control, error control, medium access, radio transmission power control, link quality estimation, network security, bandwidth utilization, localization and positioning, time synchronization, scalability, topology control, naming and addressing | [42–44] |
| | Network layer | Route discovery, forwarding node selection, neighbor discovery, reroute discovery, void bridging, energy conservation, network security, node operational lifetime, energy efficient cluster designing, throughput improvement | [42, 45–48] |
| | Transport layer | End-to-end retransmission based error control, event-to-sink transport reliability, sink-to-sensor transport reliability, congestion control, transmission power control, effect of mobility on route stability | [49, 50] |
| | Application layer | Physical topology utilization, query generation and process in different schemes of data aggregation and data generation in flat or in clustered networks | [51–53] |
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