By Jack Staub
Delphi Engineering Group
The last decade has brought fantastic change to our communications environment. Local area networks have connected our desks, cable networks connect our homes, and the World Wide Web interconnects just about everything.
The "Net" — or more precisely, a whole assortment of network technologies — transformed the world. Many of these technologies will have an equally significant impact on the military systems that we design.
With respect to military systems, the benefits of applying commercial technologies have often been viewed in terms of reduced development cost and schedule. Today, emerging network technologies give commercial off-the-shelf (COTS) systems the potential to improve military capability and readiness. In fact, for military system designers, the question no longer is "if" we will use COTS network technologies, but rather "when" we will integrate them, "how" we will stay current with and support them, and "where" we will use them.
Perhaps the most critical issue revolves around the question "what" network technologies are best suited to our applications?
As military system designers struggle to determine which one among the various network technologies is best suited to their applications they confront a series of tradeoffs. Not only must system designers address an assortment of technical issues related to hardware, software, and interoperability issues, but they must also cope with the problems of integrating any COTS technology into a military system. Among these are ruggedization and life cycle support.
Fibre Channel is emerging as the technology of choice for the next generation of localized networks in military airborne, ground-based, and naval platforms. There are many good reasons for this. At Delphi Engineering Group, we are involved with the application of Fibre Channel to key military programs such as Joint Strike Fighter, TPQ-47 Firefinder Radar upgrade, the future Virginia-class attack submarine, and F-18 Hornet strike fighter upgrade. We have also been involved with applying the same technology to industrial systems for companies such as Kodak, Qualcomm, and Toshiba Medical Systems. In this role we routinely address all the standard concerns related to the insertion of COTS technology in military systems.
Our experience has demonstrated a remarkable fact. In contrast to the common disparity between performance requirements for commercial and military applications of a particular technology, many of the characteristics that are critical to military systems are also important to the mainstream Fibre Channel Market. These important characteristics include large amounts of bandwidth, interoperability, fault tolerance, resistance to obsolescence, and upgradeability.
In particular, there is a growing number of industrial applications that mirror the military`s requirements for extended-temperature operation, deterministic behavior, minimum-latency data transfer, on-line maintenance, and integration with real-time & embedded systems.
Note that consumer-oriented interface technologies such as IEEE 1394 (Firewire), SCSI, USB, and even Ethernet do not share these characteristics. In their case, cost drives the mainstream consumer market, and consumer-grade systems users are willing to do without features like fault tolerance, and they can ignore obsolescence issues.
Fibre Channel: a network for real-time systems
Incorporating Fibre Channel opens up many options to a system designer. Fibre Channel provides a scaleable network (a.k.a. fabric) capable of interconnecting several high-bandwidth sensors, displays, processing resources, and storage systems. By using Fibre Channel, designers can separate these devices widely or closely, and can interconnect them via copper or optical links.
In addition, designers can scale the fabric easily to meet system bandwidth requirements without adversely influencing the software of the devices connected to the fabric. Fibre Channel storage devices interface directly with the fabric and can acquire sensor and processor data in real-time. Further, workstations and other computer resources can easily interface to the fabric to perform offline data analysis and system monitoring.
To the fabric, high-bandwidth sensors and display devices appear similar to hard disk drives. Processing resources can "read" and/or "write" data to these devices. Systems designers can easily add or remove these devices to and from the fabric.
SAN: commercial application of Fibre Channel
To understand why Fibre Channel is well suited to military applications it may help to understand the driving market behind Fibre Channel, i.e. the storage area network (SAN) market.
Fibre Channel is a 1-gigabit-per-second serial network technology that has been selected as the interconnect fabric of Storage Area Networks (SAN`s). A SAN typically consists of a collection of high-performance servers, switches, and large array of disk drives or tape units, all connected via Fibre Channel.
The SAN market is relatively new but has been growing at an exponential rate due to its rapid deployment with high-end servers (Internet and corporate applications), digital broadcasting, and data warehousing centers.
Fundamentally, reliability and performance, not cost, drive SAN solutions. They are designed to deliver maximum bandwidth, reliability, and scalability. High-bandwidth/low-latency switches, storage devices, and network-interface cards are all readily available. Redundancy, auto failure detection, auto recovery, and on-line maintenance are critical to the commercial SAN market.
SANs involve servers with conventional operating systems such as Windows NT, Unix, and Solaris. The Fibre Channel network primarily supports the flow of SCSI commands and data between these servers and the attached storage arrays.
By next year the Fibre Channel market will exceed $10 billion and will continue to grow for at least a decade. Today, the end users of SAN technology are primarily Fortune 500 companies and the investment in a typical SANinstallation exceeds $400,000.
ISAN: industrial application of Fibre Channel
A growing number of Fibre Channel applications are outside of the commercial SAN market. They involve real-time applications that are typically industrial in nature. This Industrial SAN market, (which we call "ISAN"), leverages the Fibre Channel technologies developed for the mainstream SAN market.
ISAN applications include medical imaging, video networking/distribution, cellular base station, ruggedized SAN, high-bandwidth data acquisition, factory automation, and commercial avionics. These systems often transfer high-bandwidth data from sensors to dedicated processing resources such as digital signal processors, distribute data between processors, and in some applications store raw data in real time to disk or tape.
ISAN`s involve processors of various types, including embedded processors as well as conventional workstations. They are real-time in nature, incorporate different operating systems, and require data to be transferred efficiently between processors, storage, and I/O devices. The Fibre Channel network must simultaneously support multiple protocols such as SCSI and IP and have the ability to add new protocols through software updates.
ISAN systems routinely include standard electronics racks such as VME or Compact-PCI. However, there is often the need to develop custom hardware for embedded and high-volume applications.
Bandwidth, reliability, scalability, and interoperability are all critical properties that Fibre Channel delivers for the ISAN market. These requirements are very similar to those encountered in the military environment.
So, the primary driving force behind Fibre Channel will continue to be the SAN market. This market will grow and fund the development of supporting technologies, improved performance, and interoperability.
The SAN and related ISAN markets share many requirements with military applications. While there are strong similarities between the needs of the SAN and military markets, there are important differences related to operating systems, protocols, and form factors. In contrast, the requirements of the ISAN market are nearly identical to those of the military market.
Delphi continues to leverage the Fibre Channel developments of mainstream SAN providers for use in ISAN and military markets. We have developed hardware interfaces and supporting software for use in real-time and embedded systems. We have optimized firmware and device drivers for high-throughput and low-latency applications. We provide design licenses and engineering support for custom applications and we screen high- performance Fibre Channel controllers for industrial and military temperature operation.
Our experience with Fibre Channel and the commercial markets that drive this technology, reinforce our belief that Fibre Channel is well suited to military and industrial applications. Moreover we believe that military systems can leverage a great deal of what is being developed for the commercial and, in particular, industrial Fibre Channel markets.
Over time, military systems will benefit tremendously from the SAN investment; but only if the military use of Fibre Channel remains totally compatible with the SAN technologies. In this case, military systems should follow and not lead or diverge from the commercial market.
Jack Staub is co-founder and president of Delphi Engineering Group in Costa Mesa, Calif. Before starting Delphi in 1995, he worked for Hughes Aircraft on the development of high-performance signal processors for radar applications. He holds engineering degrees from Lehigh, USC, and UCLA.
James Clarke is a member of Delphi`s board of directors. After graduating from the U.S. Military Academy at West Point, N.Y., with an engineering degree, he served as an Army Ranger with 82nd Airborne Division at Fort Bragg, N.C. He holds an MBA from Harvard. They can be reached by e-mail at [email protected] and jclarke@ DelphiEng.com.