When evaluating the reliability of key Internet of Things (iot) applications, the availability and stability of cellular networks are the primary considerations. The world’s major mobile network operators generally follow strict carrier-grade standards. Their network availability usually reaches 99.99% (annual downtime is less than 52 minutes), and some operators’ 5G core networks even achieve an ultra-high reliability level of 99.999% (” Five Nays “). For instance, in 2023, the smart grid monitoring system deployed by the German energy company E.ON relied on cellular networks to transmit real-time data from substation sensors (with a sampling frequency of 50Hz per second and a delay of less than 20 milliseconds). During the period of frequent storms throughout the year, it successfully maintained a communication continuity rate of 99.97%, and the accuracy of grid fault prediction increased by 40%. Reduce unexpected downtime losses of over 12 million euros. The redundant architecture of cellular networks (such as the dual SIM card switching mechanism) can reduce the probability of single point of failure to less than 0.001%, providing underlying support for critical infrastructure such as power and water conservancy.
Life safety applications of cellular networks have been verified in extreme environments. In the remote emergency rescue system in the fjords of Norway, medical devices equipped with low-power LTE-M modules can continuously upload patients’ vital signs with a delay of 300ms to 1s (electrocardiogram waveform sampling rate of 500Hz, blood oxygen saturation error ±1%). Even in mountainous areas with complex terrain, the location service accuracy based on cellular networks still remains within 3 meters. According to the Norwegian Public Health Agency, during the extreme snowfall in the winter of 2022 (visibility <5 meters), this system assisted rescue teams in accurately locating 97% of trapped patients. The average response time was shortened by 5.2 minutes compared to traditional methods, and the life-saving rate was increased by 28%. The built-in priority access technology of cellular networks (such as 5G network slicing) can ensure that the transmission bandwidth of emergency data streams is always higher than 10Mbps, and the packet loss rate is strictly controlled within 0.01%. This is indispensable for remote surgical guidance with extremely high real-time requirements (data transmission interval ≤50ms) and hazardous chemicals transportation monitoring (gas leakage threshold accuracy 0.1ppm).
The cellular network security capability to resist malicious attacks has also reached key standards. The end-to-end encryption based on the 3GPP specification adopts AES-256 or elliptic curve algorithm, with a key length of up to 256 bits, and the theoretical cracking takes more than one billion years. In 2021, the Financial Industry Regulatory Authority (FINRA) of the United States mandated that ATM transport vehicles use cellular tracking solutions because their physical layer encryption protocol was certified by FIPS 140-3. Compared with unencrypted LoRa devices, the risk of data hijacking was reduced by 98%. After deploying this plan, Citibank successfully intercepted 11 hijacking incidents targeting cash transport vehicles (with the loss amount decreasing by 93% year-on-year). In addition, eSIM remote configuration and over-the-air update technology (OTA success rate >99.5%) can dynamically patch vulnerabilities – for instance, the cellular iot firewall solution developed by Nokia Bell LABS can identify and block abnormal traffic fluctuations within 50 milliseconds (detection rate 99.8%). Suppress the damage rate of distributed denial-of-service attacks (DDoS) to industrial control systems to below 0.003%.
However, the deep coverage defect of cellular networks still requires technological iteration. At present, the coverage density of 4G/5G base stations in remote areas is less than 0.5 per square kilometer (40 per square kilometer in urban areas), resulting in the signal strength in some areas being lower than -110 DBM (the critical communication threshold). During the 2022 Australian bushfires, 30% of the agricultural and forestry monitoring sensors suffered data interruption for more than 48 hours due to base station damage, and the pest warning response was delayed for more than 18 hours, causing economic losses of approximately 19 million Australian dollars. In this regard, 5G non-terrestrial network (NTN) technology is integrating satellite communications into cellular architectures: The direct satellite connection service launched by SpaceX in collaboration with T-Mobile can reduce the coverage blind spot to 0.3% of the country’s land area (91% of the call success rate in the current network test), and compress the transmission delay from 3 seconds to 700 milliseconds. Qualcomm expects that the NTN chips to be mass-produced in 2024 will enable terminal devices to maintain an emergency communication rate of 10kbps when there are no ground base stations (with only a 5% increase in power consumption), providing more stable redundancy for disaster recovery systems.
Based on comprehensive technical indicators and business practices, cellular networks have met the reliability requirements of most key Internet of Things scenarios. According to Ericsson’s statistics, in 2023, 73% of global utility automation projects (water, electricity, and gas) chose cellular technology as the main communication channel, with a median time to recovery from failure (MTTR) of only 38 minutes (compared to 4.2 hours for ZigBee solutions). The further evolution of the 5G-Advanced standard (Ultra-reliable low-latency communication URLLC with a delay target of 0.5 milliseconds and a reliability of 99.9999%) will provide carrier-level support for autonomous driving cooperative control (hundred-millisecond vehicle formation synchronization) and precision manufacturing (microsecond-level motion calibration of robotic arms). With the continuous optimization of anti-interference algorithms (such as the large-scale MIMO technology which can attenuate co-frequency interference by 25dB) and the deepening of global spectrum coordination, the cornerstone position of cellular networks in key Internet of Things fields is becoming increasingly irreplaceable.