3G mobile networks have gained high user popularity due to the tremendous growth of the smart phone market. However, their complex signaling procedures and limited soft capacity made them vulnerable to new denial-of-service (DoS) attacks involving the control plane. More importantly, this type of frauds can also affect the successors of the 3G and their related paradigms such as smart cities. In this paper, we deeply examine the considerable signaling load of the IDLE-DCH state transitions that can be exploited by malicious entities to launch signaling DoS attacks. Besides, we investigate some state-of-art techniques proposed to combat the signaling attacks. A comparative analysis between these solutions has been conducted with regard to three pertinent criteria: cost, efficiency and overhead. The summary of results indicates that even though the randomization experiences some flaws related to the radio channel consumption, it presents the most optimal cost and overhead compared to the remaining solutions. This study opens up a new horizon for more secure 3G systems based on the randomization defense mechanisms.