Analyzing the overload of 3GPP LTE system by diverse classes of connected-mode MTC devices

As massive deployments of autonomous MTC devices jeopardize current mobile access networks with their excessive signaling, wireless industry is taking decisive steps to protect future technology from such overloads. Whereas efficient mechanisms for overload control of 3GPP Long Term Evolution (LTE) system are now in place when the devices are connecting to the network, we investigate the situation when the connection has already been established and a large number of devices send their meaningful data. In this paper, we intend to identify whether a surge in simultaneous transmission attempts by numerous connected-mode MTC devices actually threatens 3GPP LTE and characterize an overloaded scenario with a mixture of diverse device classes (e.g., low and high priority devices). Our approach combines both analysis and protocol-level simulations to conclude that appropriate overload control mechanisms may also be necessary for connected-mode devices.