Internet of Things Session Management Over LTE - Balancing Signal Load, Power, and Delay

To efficiently support and manage massive number of IoT short and bursty sessions, current LTE system needs to reduce signal load generated by IoT session setup/synchronization, while balancing the system performance, such as UE power consumption and delays to crucial traffic. In LTE, Radio Resource Control (RRC) and Discontinuous Reception (DRX) affect power consumption, signal load and delay. To address this problem, we provide a session management methodology suitable for IoT traffic over LTE. Our analysis starts with a Markov Chain analysis of the impact of DRX parameters. This is followed by an optimal uplink scheduler design and an IoT-aware adaptive DRX algorithm at the client, both of which modulate the tradeoff among signal load, delay and power consumption. Scalability is also considered in this work by providing a high-priority clustering-based adaptive DRX algorithm at eNB. Simulation results show that for packets with 0.1s delay, our scheduler outperforms ‘Tx now’ (and ‘Wait Till Deadline’) by 50% (and 30%) in power saving, by 60% (and 15%) in signal saving. With knowledge of the traffic pattern, IoT-aware adaptive DRX can further reduce signal load by at least 25%, especially for delaysensitive traffic.