The promise of Open APIs: Is write-once software in our future?

Story

October 06, 2010

Steve Edwards

Curtiss-Wright

The embedded military market is poised to take the next big leap in improving time to deployment through the adoption of Open APIs to speed system application development. Open APIs can ease heterogeneous hardware technology integration, drastically cutting time, cost, and complexity for building larger multimode systems.

Time to deployment is a key driving force in the embedded military market. The faster advanced technology is delivered to the field to support the warfighter and save lives, the better. The COTS approach has significantly helped in speeding the delivery of commercial hardware and in furthering open-standards body efforts. For example, the recent OpenVPX/VITA 65 work will help cut development time for high-performance embedded systems. Now, the embedded military market is poised to take the next big leap in improving time to deployment through the adoption of Open APIs to speed system application development. Open APIs can ease heterogeneous hardware technology integration, drastically cutting time, cost, and complexity for building larger multimode systems.

OpenFabrics tackles heterogeneous systems

Today, embedded system integrators must deal with myriad fabric choices – such as PCI Express, Serial RapidIO, Ethernet, and InfiniBand – and a wide variety of processors such as Intel, Power Architecture, GPGPUs, and FPGAs. Getting data to move back and forth efficiently between these various processors and fabrics within a fixed Size, Weight, and Power (SWaP) envelope is a daunting task. Initiatives in the commercial market are underway to address the challenge of integrating heterogeneous systems. One such initiative, led by the OpenFabrics Alliance (www.openfabrics.org) has developed a middleware stack, known as the OpenFabrics Enterprise Distribution (OFED). The key component of this open source initiative is OpenFabric User VERBS (OF-UV)-enabled software, such as OpenMPI, that communicates through the VERBS API layer, the OS, the BSP, and the fabric. OpenFabrics supports Windows, Linux, OpenSolaris, and 10 GbE and InfiniBand. It enables the programmer to code without concern for which OSs or fabrics the system hardware is based on.

Getting to “write-once” software

The embedded community should consider this approach. Proprietary APIs typically only support hardware supplied by the API vendor, and it is difficult to adapt to hardware from other manufacturers. Open APIs are agnostic to fabric, processor, or the system at the board level. The user program writes to middleware that is abstracted to a layer from which the middleware talks to the hardware. This means software can be developed earlier, without having to wait for the target hardware to become available. The promise is that software is written once, but scales with the underlying technology without needing to be rewritten as the number of cores grows and the fabrics evolve from, for example, 10 Gbps today to 100 Gbps within four years.

Multicore drives software complexity

The increased use of multicore processors is driving embedded integrators to use ever more complex software. Flat memory model real-time OS development will become less common for the most sophisticated applications. Mil/aero signal processing applications are turning to multicore processors, with faster and greater quantities of memory and greater bandwidth requirements. By using commercial abstraction software via Open APIs, developers will not have to optimize their code to the byte level. Processors are becoming fast enough to meet many latency requirements without needing to provide “perfect real time”; “near real time” will frequently suffice. One indication is that some customers are now deploying radar systems based on Windows XP that would have been unheard of a decade ago.

The MCAPI initiative

Another Open API initiative is Multicore Communication API (MCAPI), led by the Multicore Association (www.multicore-association.org/home.php). This group is working to maximize the efficiency of embedded applications as they are distributed across multiple heterogeneous boards. The MCAPI is in the early stages, and its 1.0 spec is expected to be completed by the end of this year.

As an embedded community, we are just beginning to engage in the Open API endeavor. In a perfect world, one could leverage all the fruits of the commercial market, but the SWaP requirements demand specialized components that will likely limit adoption. Mapping applications to Open APIs is a trade-off. Running open-standards middleware requires a design sacrifice of some memory, bandwidth, and processor speed as more complexity is added in the data transport, OS, and middleware.

Speeding deployment with Open APIs

Embedded military vendors are now seeing increased interest from military market customers for high-level middleware support, such as Distributed Distribution Service (DDS), OpenMPI, and VSIPL++, which combines a math library function with a data transport. With Open APIs, customers see the potential to decrease their time to deployable product by getting development started earlier. They can also leverage data transport abstraction to run on the actual embedded system later in the development cycle.

At Curtiss-Wright, for example, we plan to contribute and support these Open APIs on our rugged hardware while optimizing the total system SWaP, enabling mil/aero customers to develop and deploy more rapidly. To ensure that the military COTS community can optimize its use of these burgeoning Open API standards efforts – and that its unique market requirements are heard and understood as these standards are developed – the embedded board and subsystem community should support the MCAPI and OpenFabrics initiatives. Increased communication and involvement among the embedded industry, competitors, customers, and these open source software groups could benefit us all.

To learn more, e-mail Steve at [email protected].