NB-IoT: Reliable, power-efficient IoT for challenging locations

NB-IoT offers long battery life, deep signal penetration, and scalable connectivity for devices transmitting small amounts of data infrequently. Supported by the GSMA Mobile IoT initiative and standardized by 3GPP, NB-IoT is now widely recognized as one of the most robust LPWAN technologies available for industrial and utility-grade IoT applications

At Com4, we enhance NB-IoT by combining it with a multi-mode IoT SIM that enables seamless switching between NB-IoT, LTE-M, 4G, 3G, and 2G networks under a single price plan. This flexibility ensures service continuity across borders, even in markets where NB-IoT roaming is not yet available.

Table of Contents

What is NB-IoT?

Technical overview of NB-IoT

NB-IoT vs LTE-M vs 2G/3G/4G

Key advantages of NB-IoT

Limitations of NB-IoT

Com4 NB-IoT coverage

Example use cases

Security in NB-IoT

Why choose Com4 for NB-IoT deployments

What is NB-IoT and why it matters

NB-IoT is a Low Power Wide Area Network (LPWAN) standard developed specifically for IoT applications. Built on licensed LTE spectrum, it is designed to connect stationary devices that need to operate for years without maintenance and are often placed in areas where coverage is limited, such as basements, underground utility rooms, remote rural areas, or deep inside industrial complexes. By using a narrow frequency band and advanced signal repetition techniques, NB-IoT achieves exceptional indoor and underground penetration—something that traditional cellular networks like 2G, 3G, and even 4G LTE often cannot match.

The technology is particularly valuable for devices that transmit small amounts of data periodically rather than continuously, such as water meters that send usage data once a day or environmental sensors that report readings every few hours. This efficiency is achieved through advanced power-saving modes like Power Saving Mode (PSM) and Extended Discontinuous Reception (eDRX), which allow devices to “sleep” for extended periods without consuming significant battery power.

Technical overview of NB-IoT

NB-IoT is a 3GPP Release 13 specification designed for stationary, low-power, low-data-rate IoT applications. Unlike unlicensed LPWAN technologies, it operates in licensed LTE spectrum, ensuring predictable performance and carrier-grade security.

Table 1: Technical characteristics of NB-IoT

Source: GSMA Mobile IoT initiative, 3GPP Release 13 specifications

NB-IoT vs LTE-M vs 2G/3G/4G

While LTE-M and NB-IoT are both LPWAN standards, they serve different IoT needs.

Table 2: A comparison of NB-IoT, LTE-M, and legacy 2G/3G/4G technologies for IoT connectivity

Key advantages of NB-IoT

Extended coverage

NB-IoT provides a link budget improvement of ~20 dB over GSM, enabling connectivity in basements, tunnels, and dense urban areas.

Long battery life

Devices using NB-IoT can operate for up to 10 years on a single battery with low duty cycles.

High scalability

Each NB-IoT cell can support tens of thousands of devices, making it suitable for large-scale smart city and utility deployments.

Cost-efficiency

NB-IoT modules are simpler and cheaper than LTE Cat-1 or 5G modules, with costs expected to continue decreasing as adoption grows.

Security and reliability

Uses the same LTE-grade authentication and encryption mechanisms as traditional cellular networks.

Limitations of NB-IoT

• Weak support for mobility: NB-IoT does not offer robust support for mobility. While it can maintain connections for devices in motion, it lacks the seamless handover capabilities of technologies like LTE-M, leading to potential performance degradation and increased power consumption when devices move between cell towers.
• Limited data throughput: Optimized for kilobits per second, not suitable for high-bandwidth IoT.
• Latency: Can reach several seconds, making it unsuitable for real-time applications.
  Roaming maturity: International NB-IoT roaming is expanding but not yet universal.

Com4 NB-IoT coverage

Com4 provides dedicated NB-IoT access across Europe, with strong footprints in:

• Norway and Sweden – National NB-IoT deployments from major operators, enabling coverage even in rural and indoor environments.
• Germany – Nationwide NB-IoT through partnerships with Deutsche Telekom, ensuring carrier-grade service quality.
• Pan-European support – NB-IoT coverage extended through multiple partner networks across Central and Eastern Europe.

Table 3: Com4 coverage for NB-IoT and multi-mode SIM

This dual approach ensures that IoT deployments remain future-proof and globally scalable, while still taking advantage of NB-IoT’s unique characteristics in markets where it is available.

Example use cases

• Smart Metering:  Gas, electricity, and water meters in underground or indoor installations.
• Environmental Monitoring: Long-term air quality or noise measurement in urban areas.
• Precision Agriculture: Soil and crop sensors in remote fields with no power supply.
• Industrial Equipment Monitoring: Stationary equipment in manufacturing plants.

Security in NB-IoT

Security is one of the most critical considerations in any IoT deployment. Many NB-IoT applications handle sensitive or business-critical data: from smart meters reporting household energy usage to industrial sensors monitoring pipelines or infrastructure. Protecting this data from interception, manipulation, or unauthorized access is essential not only for compliance but also for customer trust and operational reliability.

NB-IoT is built on the 3GPP cellular security standards, which are the same frameworks that have safeguarded mobile networks for decades. Unlike unlicensed LPWAN technologies such as LoRaWAN or Sigfox, NB-IoT benefits from operator-managed infrastructure and licensed spectrum, which provide higher levels of reliability and protection. At its core, NB-IoT uses SIM-based authentication, where each device is equipped with a unique, tamper-resistant identity. This enables strong, hardware-based authentication that prevents device spoofing or cloning. The standard also ensures mutual authentication, meaning that both the device and the network must verify each other before communication begins, effectively reducing the risk of man-in-the-middle attacks. In addition, data is encrypted during transmission, typically with 128-bit algorithms, and signaling integrity protection ensures that messages cannot be altered without detection.

The GSMA IoT Security Guidelines provide further direction for implementing best-in-class protection in IoT deployments. These guidelines recommend a layered approach to security, beginning with unique device identity management through SIM, eSIM, or iSIM technology, and extending to end-to-end encryption that secures data from the device all the way to the application server. GSMA also highlights the importance of secure lifecycle management, ensuring that devices can be safely provisioned, updated, and eventually decommissioned without introducing vulnerabilities. Regular testing and monitoring are also emphasized, since IoT deployments often run for 10 to 15 years and need to remain secure in the face of evolving threats and regulatory changes.

While the 3GPP framework provides a strong foundation, Com4 enhances NB-IoT deployments with additional layers of security tailored for enterprise and mission-critical applications. One such option is the use of Private APNs (Access Point Names), which create closed user groups within the cellular network, effectively isolating IoT devices from public internet exposure. Com4 also supports VPN and IPsec tunneling, which establish secure and encrypted channels between the customer’s backend systems and Com4’s core network. 

For organizations requiring advanced segmentation, traffic can be separated by device groups or applications, ensuring that no single compromise can affect an entire fleet. In addition, Com4 customers benefit from the possibility of implementing end-to-end encryption on the application layer, ensuring that sensitive information remains protected beyond the cellular transport level.

For customers planning NB-IoT deployments, Com4 recommends following a set of best practices to maximize security. The use of IoT-optimized SIM, eSIM, or iSIM credentials ensures that device identities remain tamper-resistant and hardware-secure. Private APNs or VPNs should be deployed whenever possible to reduce exposure to the public internet. For particularly sensitive deployments, end-to-end encryption is advised, so that even if traffic is intercepted outside the operator’s control, the information remains inaccessible. Organizations should also implement device monitoring and anomaly detection, since unusual traffic patterns can often signal an attempted compromise. Finally, it is critical to design for secure updates, ensuring that devices deployed for long lifecycles can be patched and protected against newly discovered vulnerabilities.

In summary, NB-IoT provides one of the most secure environments for IoT connectivity by leveraging the robust 3GPP cellular security framework. When combined with the GSMA’s recommended best practices and Com4’s enterprise-grade enhancements such as Private APNs, VPNs, and end-to-end encryption, enterprises gain a connectivity solution designed for the highest levels of trust and resilience. This makes Com4 NB-IoT an ideal choice for mission-critical applications where data integrity, privacy, and long-term reliability cannot be compromised.

Why Choose Com4 for NB-IoT Deployments

With more than 14 years of IoT connectivity experience, Com4 ensures NB-IoT deployments are:

• Backed by expert guidance on device selection and module compatibility.
• Supported by predictable pricing models.
• Enabled by partnerships with leading European operators for coverage and reliability.
• Future-proofed with multi-mode connectivity for international projects.

NB-IoT represents one of the most reliable and cost-effective solutions for connecting stationary, low-data IoT devices in coverage-challenged environments. Supported by GSMA-backed standards and commercial operator rollouts worldwide, it enables deep penetration, long device lifetimes, and large-scale deployments at low cost.

When combined with Com4’s multi-mode IoT SIM and global coverage, NB-IoT becomes a versatile connectivity option for industries such as utilities, agriculture, manufacturing, and smart cities.

For more details on NB-IoT and global Mobile IoT deployments, visit the GSMA’s dedicated resources on NB-IoT and the Mobile IoT Deployment Map.