Abstract Cellular Internet of Things (CIoT) is considered a suitable technology to provide connectivity to IoT devices and support machine type communication (MTC). CIoT relies on cellular networks, such as 5G, to handle the increased demand for data and avoid overload. However, the limited capacity of the Random Access Channel (RACH) represents a challenge for implementing real-time IoT applications in 5G Radio Access Networks (RANs). The information update generation and Random Access Protocol (RAP) play a crucial role in ensuring timely updates. This paper presents a performance analysis of the impact of information update generation patterns on the RAN in CIoT when the number of IoT devices and information update frequency increase. An extensive simulation study was conducted, considering MTC and H2H (human-to-human) traffic with varying access request intensities. We determine the maximum information update frequency to provide a highly successful access probability over the RAN.