Reducing Signaling Overhead in 5G Mobile Network for IoT Device Mobility

Internet of Things (IoT) services over 5G mobile networks will have unique communication characteristics of massive connectivity and sporadic small-scale data transfer. These characteristics increase the signaling overhead of C-plane message exchange associated with connection management in RAN and mobile core. 3GPP has standardized Small Data Transmission with RRC-INACTIVE that reduces this overhead. However, a new type of IoT service accompanied by device mobility is emerging. The 3GPP standard approach does not adequately account for the frequent device mobility and does not sufficiently reduce the overhead for these new IoT services. This paper proposes a new communication method for the mobility of IoT devices, which suppresses the signaling overhead of RAN and mobile core. It releases the device status management of RAN by introducing simplified status information. Our simulation results showed that the proposed method suppresses the signaling overhead compared with the 3GPP approaches. Specifically, the proposed method could reduce the signaling message exchange up to 28%.