Gateway Implementations with RISC-V

Using RISC-V for Efficient IIoT Gateway Implementations

Alex Pluemer for Mouser Electronics

Reduced instruction-set architectures (ISAs) like RISC-V provide greater efficiency and less drag on resources than their more complex counterparts. IIoT applications often require high levels of connectivity and cooperation between modules while keeping costs down by reducing power consumption. The growth of AI-based functionality presents opportunities to add new revenue streams while continuing to improve response time and reduce costs. The IIoT and the variety of use cases in which it implements gateways and routers continues to expand every day. It’s possible that RISC-V is a catalyst for accelerating that expansion. There are a variety of ways gateways are utilized in IIoT implementations and the benefits of RISC-V make it an advantageous solution for optimizing those applications.

Industrial gateways and routers are implemented in a variety of use cases in both the public and private sectors.  Municipalities use gateways to manage/optimize traffic flow by connecting remotely from a central location or from the roadside itself to monitor and program traffic lights, motion sensors and cameras.  Manufacturers and retailers implement gateways to monitor inventory and track outgoing shipments in real-time, reducing shipment and restocking-related delays. Large-scale operations employ industrial gateways/routers to build and manage their utility networks, increasing their energy efficiency and improving safety while reducing overall cost. Enterprises that operate and maintain large fleets of commercial or passenger vehicles use gateways to track vehicles along their journeys and utilize big-data-driven AI functions to perform predictive maintenance, a key factor in keeping vehicles in working order and minimizing repair/replacement costs. Banks and financial institutions use gateways to operate large networks of ATMs, delivering secure remote connectivity to monitor cash levels and providing video surveillance. Remote management of harsh or rugged manufacturing environments through gateways/routers can protect the workforce and reduce downtime for maintenance and/or cleanup.

Modern factories commonly employ detailed material management and control (Figure 1). Materials move along intelligent conveyer belts with sophisticated tracking and inspection sensors to make sure they move smoothly from station to station ─ at each station, various materials are gradually integrated until the final product is assembled. Each station may be required to manage inventory of the materials it’s working with ─ mechanical and electronic modules, fasteners, cables and packing material ─ to avoid shortages and overruns, both of which drive up costs. Gateway elements are deployed to monitor and control the various processes that go into completing product manufacturing while providing critical data to human (or AI-based) operators.  Data is often communicated to the cloud to help manage inventory, predict needed maintenance and optimize manufacturing efficiency.  Gateways provide the glue that connects the myriad protocols and physical interfaces used in such an environment.

Figure 1: Modern factories use intelligent conveyor belts to make sure things move smoothly from station to station (Source: Shutterstock.com/d1sk)

An IIoT gateway for this application like this one is required to support all the common protocols needed on a factory floor─ such as wireless, Ethernet, USB, CAN, UART and analog, as well as the type of standard digital interfaces used in Programmable Logic Controller (PLC) modules. These protocols also require periodic updates for bug fixes and patches ─ security is critical for these updates, both to protect against malicious attacks from malware and viruses and to protect sensitive manufacturing data as it moves from the gateway to the cloud. Gateways must be flexible and easily reconfigurable when stations need to be added or the processes/protocols change. Assessing and reconfiguring the manufacturing flow in order to improve efficiency, reduce power consumption and waste and keep inventory overhead to a minimum is a constant struggle. The operating system, whether it’s an RTOS or a full operating system like Linux, also must be adaptable and easy to modify/upgrade. Ensuring efficient data flow to the cloud is critical for big-data-oriented AI functions that require continuous data from sensors and data aggregators in and around the IIoT gateway.

Reduced ISAs like RISC-V can meet the key requirements of an IIoT gateway application while improving overall efficiency and providing the flexibility necessary to adapt to the ever-evolving landscape of a manufacturing environment.

Efficiency

One of the fundamental advantages of the RISC-V ISA is its processing efficiency. Simple CPU operations use memory directly without the need for specialized processor registers, increasing speed and reducing the required memory footprint. With a cache subsystem, frequently used locations are automatically available with reduced access times – reaping the benefits of fast specialized register access without complicated and less efficient coding.  Gateways benefit from this advantage with low power and small code space -- additionally, gateways are very data transfer intensive because data packets are typically only transferred, broken down or ‘stitched’ together. Minimal processing is needed to change from one protocol to another, making efficient memory movement a key benefit.  More efficient processing also helps implement AI-oriented gateway functions for identifying unusual events and predicting potential issues before they become problems.

Flexibility and Protocol Support

Gateways need to be flexible at the protocol, operating system, physical connectivity and modular in construction. The RISC-V open source architecture makes it easy to support a variety of protocols and to adapt to changing requirements. Having access to the source code for peripheral drivers and stacks and the associated protocols makes it easy to modify them as needed, both during development and even after deployment. This makes it easy to modularize peripherals and protocols so they can be easily swapped, updated, or enhanced as industry standards change. This can extend the lifetime of an IIoT gateway and reduce the overall system deployment cost -- a key factor in IIoT implementations.

Security and Cloud Connectivity

RISC-V hardware-based security is needed to implement the root of trust, the bedrock of any robust security system. The root of trust is the known secure starting point for a host of security-related functions such as secure boot, cryptographic computations, secure key and certificate storage. The root of trust is commonly supported with specialized hardware for protecting secured data and peripheral functions, implementing tamper protection, generating keys and providing secure updates to application software. When system requires the use of cloud storage, the gateway can use trusted cryptographic standards to protect data to and from the cloud (Figure 2). With open source implementations available for encryption, decryption, certificate management and secure data communication protocols, the developer has access to all the security-related code, making it easier to test and verify the robustness of the design. Additionally, the ability to customize and upgrade the code as needed for specific application requirements -- without the need to wait for a third party to develop and release periodic updates -- is an additional benefit of an open source environment.

Figure 2: The gateway can use trusted cryptographic standards to protect data to and from the cloud. (Source: shutterstock.com/ sdecoret)

Conclusion

Gateways will continue to evolve and change as the IIoT environment produces new applications and revenue streams. As they change and become more complex, additional processing power will be required, meaning more data processing within the gateway to minimize data traffic to the cloud will also be needed. This will require adaptive processing, perhaps using AI-based algorithms to quickly respond to changes in data traffic patterns and processing requirements. RISC-V flexibility, efficiency and adaptability will continue to provide implementation advantages as gateways evolve in reaction to the changing demands of the IIoT.