Launching a market-ready IoT product requires more than just a clever concept. It demands a great understanding of embedded system design and the challenges in embedded system development. For engineering leads and product owners, the transition from a functional prototype to a reliable, scalable IoT device is where the most significant technical hurdles emerge. From balancing power efficiency with real-time processing to navigating the shifting landscape of connectivity protocols, these design choices can make or break a product’s roadmap. In this guide, we break down the most critical challenges in embedded design for IoT and how to navigate them without compromising on performance or security.
The Critical Role of Hardware Strategy in IoT Development
There are things in the development process that cannot be skipped, and one of them is hardware design. While we might have the best idea for a product, without a great plan and proper component selection, it will stay an idea forever. Preparing a careful product roadmap is the starting point for future development and IoT device scalability, particularly in PCB design, which plays a crucial role. While selecting hardware for your IoT device, we have to answer one key question: whether we choose pre-certified modules or create a custom design from scratch.
Pre-certified Modules
With pre-certified modules, there are clear benefits, such as a faster development process, reduced regulatory testing, and allowing a product to reach the market faster. However, using them also brings a few significant downsides that every team must consider. First of all, because you are paying a premium for a pre-made module, your unit cost per device will be much higher. While this might not hurt when making a small batch of 100 or 1,000 units, it will quickly eat into your profit margins as soon as you scale up production. Modules are also physically larger than discrete components, which can place real constraints on your PCB design if you are trying to build a very small or slim device — limiting how efficiently you can arrange components and route connections across the board. Also, if the module vendor is experiencing supply chain shortages or decides to stop manufacturing that specific module, your production line can easily get blocked.
Custom Design PCB
Using a custom PCB design gives us full flexibility over IoT device size, microcontrollers, sensors, and all the specific components we want to include in our product. The embedded system development process might take longer than simply using off-the-shelf components, but the strength of having total control over the design process and system parameters is substantial. Furthermore, when scaling up to mass production, the unit cost will be significantly lower, allowing you to either raise your profit margins or lower the final price for the end customer.
But it also has some drawbacks, like the necessity of certification. A custom PCB requires going through the full compliance certification process for standards like CE, FCC, or UKCA, which are mandatory to sell IoT devices legally. Another critical phase that cannot be skipped is the testing process, during which you might discover that certain parts of the hardware need to be redesigned to work reliably in the real world.
Challenges in Embedded System Design for IoT Devices
Once you determine your hardware strategy, several other critical technical challenges emerge that require careful planning and execution – starting with security.
Security Issues
Security is a huge concern in IoT devices for both the manufacturer and the customer. Most of these concerns can be fixed in software, but IoT devices are hardware-dependent and need to run securely in a real-time embedded environment. In order to achieve functional security requirements, embedded IoT systems must execute a variety of control functions that require security and must eliminate any unacceptable risks. Cryptographic algorithms should be used to secure the system’s design. It covers a variety of methods for securing all aspects of embedded systems, from prototype to production and the sale process.
Connectivity
Alongside security, choosing the right connectivity setup is another fundamental hurdle in embedded system development. There are many ways to connect a product to the internet, such as Wi-Fi, Ethernet, cellular, LoRa, or a Bluetooth bridge. Each option presents unique advantages and disadvantages, along with specific software principles that developers must master to ensure reliable hardware operation. This becomes a complex challenge when factoring in additional considerations, such as which communication protocols to use – like TCP/IP or UDP and whether the architecture requires supporting multiple protocols simultaneously.
Testing Problem
Bringing all these hardware, security, and connectivity choices together reliably requires proper testing, verification, and validation, which is a challenging process in itself. Embedded system developers use hardware-based test tools for testing. Embedded hardware testing refers to system performance, consistency, and validation in accordance with the product requirements. Verification is ensuring that functional verification is implemented correctly. Validation refers to whether the product complies with the requirements and meets all quality standards.
Rapid Technological Changes
Every year more powerful systems emerge, new technologies are being developed, and existing ones make huge leaps. Concepts such as artificial intelligence are now used in IoT. Developers are beginning to discover that existing technologies are changing faster than they can learn. For this reason, an IoT embedded system developer needs to learn to update his skill set quickly.
Key Takeaways
- Embedded system development begins with a hardware strategy: pre-certified modules offer fast time-to-market and simpler compliance, but come with higher unit costs, a larger PCB footprint, and supply chain lock-in.
- Validate market demand with pre-certified modules for Version 1.0, then transition to a custom discrete PCB to maximize margins as production scales.
- Custom PCB design gives your embedded system development team full control and lower unit costs at scale, but requires longer lead times, carries higher redesign risks, and demands mandatory certifications (CE, FCC, UKCA).
- Security must be built into the embedded system from the start — not bolted on later — using cryptographic protections, Secure Boot, and Hardware Root of Trust.
- Match connectivity protocols (Wi-Fi, Cellular, LoRa, BLE) to your power and latency budgets, and validate real-world performance using hardware-based test tools early in the development cycle.
Conclusion
The challenges in embedded system design for IoT devices are real, complex, and faced by the vast majority of manufacturers bringing connected products to market. From hardware strategy and PCB design decisions to security, connectivity, and rapid technological change, each layer of development introduces its own set of risks. Whether you are weighing pre-certified modules against a fully custom PCB or navigating the right connectivity protocol for your use case, these choices carry long-term consequences for scalability, cost, and reliability. Fortunately, in most cases, proven solutions already exist in various formats. The challenges in embedded system development are certainly not insurmountable when teams take the time to understand them thoroughly. The key is for developers and product leads to stay ahead of emerging problems, continuously sharpen their skills, and make informed design decisions early — before those decisions become costly to reverse.
Frequently asked questions
Can we launch with a pre-certified module and transition to a custom PCB later?
Yes, this is a standard industry approach. Many engineering teams use pre-certified modules for Version 1.0 to validate market demand and generate early revenue. Once production volume scales and funding allows, they redesign the hardware into a discrete (chip-down) PCB to optimize unit margins.
How do we prevent IoT vulnerabilities that lead to unauthorized access or data leaks?
Every connected device is a potential doorway into your network. Preventing hardware takeovers and data leaks requires protecting both the data in transit and the physical chip. This means pairing proper communication setups (like encrypted protocols) with hardware-anchored defenses, such as Secure Boot and Hardware Root of Trust, to ensure untrusted code can never execute on the device.
