The Advanced TOMAHAWK Weapons Control System for Submarines

The problem of fast filtering in bridging Ethernet local-area-networks (LANs) through high speed fiber distributed data interface (FDDI) networks is addressed. A filtering algorithm, called MFA is introduced, which sets the minimum power requirements for a bridge connecting an Ethernet LAN to an FDDI backbone. A hardware solution based on the use of content addressable memories is described. The MFA tries to avoid packet broadcasting on the FDDI ring. This is done by keeping track of remote Ethernet addresses coupled with the FDDI address of the related bridge. With MFA, the bridge performs filtering and routing operations only on packets coming from the Ethernet side, while the filtering from FDDI side is directly performed by the FDDI media access control. As a result, MFA has only to cope with the maximum Ethernet transmission rate, slower by one order of magnitude, and thus requiring less processing power. >

Performance issues of the FDDI-II protocol, an upward-compatible enhancement of the basic fiber distributed data interface (FDDI), are discussed. The main characteristics of the FDDI protocol are examined. The performance of FDDI-II is studied for scenarios including asynchronous traffic, synchronous traffic and isochronous traffic. The results make clear that basic FDDI meets the requirements imposed by traditional local area network (LAN) application and that from a performance point of view FDDI-II is an excellent candidate for complex communications environments. When compared to the distributed-queue-dual bus (DQDB) protocol, FDDI-II yields much better efficiency in traditional LAN applications. >

Safety-critical systems and in particular mixed-criticality systems require spatial and temporal separation for their hosted applications and functionalities. Additional constraints are using Commercial Off -- The -- Shelf (COTS) components, portability and determinism. These items are required for economic success for products with low piece numbers and long life-cycles like aircraft. Available embedded processors lack means for spatial separation of Input/Output (I/O) components like an Input/Output Memory Management Unit (IOMMU). The objective of this paper is to provide spatial separation for I/O in COTS mixed-criticality embedded real-time systems like avionics with minimum possible impact on performance (transfer time, transfer rate, Central Processing Unit (CPU) usage). The three main contributions of this paper are: (1) The presented Input/Output Memory Protection Unit (IOMPU) enables to upgrade spatial separation for I/O to a system by using COTS components and Non-Transparent Bridge (NTB) technology. In addition, the IOMPU concept is compatible with existing temporal separation solutions. (2) The paper shows a prototype implementation and a potential use case in context of hardware-based I/O virtualization. (3) The evaluation in this paper demonstrates that the IOMPU concept is practically applicable. The performance overhead (transfer time, transfer rate) is below 0.88%, which is almost negligible, particularly compared to state-of-the-art software-based solutions.

Using commercial off the shelf (COTS) computing equipment in military aircraft applications may cause harmful electromagnetic interference (EMI) to other on-board systems, including communication and navigation equipment. An electromagnetic compatibility (EMC) design approach to successfully integrate COTS equipment into an existing military aircraft is described. The following system design and development steps are outlined: (1) requirements definition, (2) preliminary EMC analysis, (3) EMC control measure design, (4) COTS equipment EMI characterization tests, and (5) system level EMC verification.

The survivable adaptable fiber optic embedded network (SAFENET) program, an effort by the US Navy to develop standard computer network profiles that meet the requirements of navy shipboard mission-critical computer systems, is discussed. The two SAFENET standards currently in development are described. The distinction between them is restricted to the commercial local area network (LAN) upon which each is based. SAFENET I uses the IEEE 802.5 token ring LAN, which operates at 16 Mb/s. SAFENET II uses the fiber distributed data interface (FDDI) LAN, which operates at 100 Mb/s. The SAFENET transmission system, optical power budget, and application methodology are examined. >

In this paper, we present a performance analysis of how effective video server applications can be supported on personal computers (PCs) connected through a local area network (LAN). We considered both the standard 16-Mbit/s token ring and a 100-Mbit/s token ring, which follows closely the specifications for the Fiber Distributed Data Interface (FDDI). We examined three I/O architectures for a PC-based video server: an interrupt-driven I/O architecture, a peer-to-peer I/O architecture, and a concurrent, object-based I/O architecture that we proposed. The video server must support multiple MPEG-1 video streams at the same time to multiple clients on the LAN. We found that the network protocol layers require a lot of processing power, and that an implementation of our proposed I/O architecture, which takes advantage of the available power of the host processor to off-load I/O adapters, can deliver much better performance, and is more cost-effective, than other I/O architectures in a video server environment.

The increase of complexity and miniaturizing level of Aerospace platforms make use of commercial off the shelf (COTS) components constitute a plausible alternative to the use of military or rad-tolerant components. In this work, giant magnetoresistance commercial sensors are studied to be used as COTS, the next missions to be launched in the framework of the Spanish National Space Program: OPTOS and SEOSAT. This technology of magnetic sensors is interesting due to their high operating range up to 2mT and the high temperature dynamic range from −50 up to 150°C. However, in contrast, it presents high hysteresis and nonlinearity, temperature dependence, and poor repeatability. To improve the hysteretic, nonlinear and nonrepetitive behavior, a method consisting of a combination of reset and biasing has been designed and implemented for the ±75μT linear region centered around 300–375μT biasing field.

: Small unmanned systems provide great utility to military applications due to their portable and expendable design. These systems are, however, costly to develop, produce, and maintain, making it desirable to integrate available commercial off the shelf (COTS) components. This research investigates the integration of COTS components through the development of a modular unified command and control (C2) architecture for heterogeneous and homogeneous vehicle teams to accomplish formation flocking and communication relay scenarios. A vehicle agnostic architecture was developed to be applied across different vehicle platforms, different vehicle combination, and different cooperative missions. COTS components consisting primarily of open source hardware and software were integrated and tested based on the positional accuracy, precision, and other qualitative measures. The resulting system successfully demonstrated formation flocking in three of four vehicle combinations, with the forth still demonstrating leader follower behaviors. The system achieved at best a mean positional error of 0.99m, a standard deviation of 0.44m, and a DRMS of 0.59m....

In the past, functional test requirements (FTR) or test requirement documents (TRD) and test program sets (TPS) were standalone items developed by individual engineers. In some cases one engineer would write the FTR/TRD and another would develop the TPS. Commercial ATLAS FTRs are prepared in ARINC 616 and 626 ATLAS. Military TRDs are written in IEEE ATLAS 716 versions. Previous test reuse attempts have not been successful because additional software, like browsers, is required to support these efforts. It was difficult to justify writing new software (for example browsers) to manage the application software. Today, commercial off the shelf (COTS) tools are in place to browse and view information from circuit diagrams to documents to source code. These tools can develop hierarchies to organize the information. These COTS tools are available throughout Boeing on many types of workstations and personal computers on every engineer's desk. This paper discusses how a reusable test library (RTL) is being developed using commercial off-the-shelf (COTS) tools such as Mosaic to address commercial and military test applications. It describes each of the tools and the process to develop TPSs using the reuse library. It defines the metrics and the benefits achieved.

The author examines two broadly supported ring designs, IEEE 802.5 and the Fiber Distributed Data Interface (FDDI), X3T9.5 currently emerging as local area network (LAN) standards, and explores the basis of this interest in ring topologies. The advantages that ring designs offer are presented, and on this basis a proliferation of rings is envisioned for the next decade.

In modern times, where the speed of transmission is of utmost importance, often need arises for a reliable transmission medium. With innovations in LAN (local area networks) such as FDDI (fiber distributed data interface), fiber optic data links and associated interface schemes are gaining more and more acceptance and actually are becoming real necessities. In this article, the author describes a simple design methodology for a fiber optic data link and presents criteria to evaluate the performance and frequency response properties of these data links. In addition, a simple wavelength division multiplexing (WDM) scheme for improved data rate is also presented.

The aim of this work has been to graphi cally simulate the protocols employed for 100 Mbps token ring local area network (LAN), using the fiber-optic medium, known as Fiber Distributed Data Interface (FDDI), and to study its performance evaluation. In the computer based simulation, the effort has been made to describe the working of the protocols using graphical, dynamically working models. Also performance characteristics, such as Throughput Vs Token rotation time, Throughput Vs Ring Latency, Throughput Vs Data Arrival Rate are obtained. The asynchronous priority level throughput for different data arrival times are tabulated. From the characteristics, it is found that the relative difference between the ring latency and the token rotation time (TRT) has a significant effect on the maximum total throughput. Also with the higher value of the TRT the throughput increases faster compared to lower TRT values.

This paper discusses single and multiple token rings, describes major aspects of their architecture, and discusses in detail the performance issues arising in the design of such local area networks. Following a survey of analytical queueing models to describe the basic token-ring operation, three topics are discussed in detail: 1) The IEEE 802.5 Token Ring and its performance; 2) performance aspects of the ANSI Fiber Distributed Data Interface (FDDI) token ring, and 3) performance questions arising in the interconnection of token-ring networks.

The use of diverse standards while developing web and mobile technologies brings new challenges when it comes to flexibility, interoperability, customizability and extensibility of the software systems. In addition, such systems in most of the cases are closed, thus make the development and customization process for system designers, developers and end-users a challenging effort. All these developments require further research attention. This work addresses these challenges from open system architecture perspective. The proposed approach is based on practical development efforts, and theoretical research including state of the art projects and definitions related to open architectures that we surveyed. The initial results indicate that a combination of service-oriented approaches with open source components and open standard data formats pave the way towards an open, extensible architecture. The core contribution of this research will be (a) an open architecture model and (b) the developed system itself based on the model, and (c) the benefits of applying open architecture approaches throughout the development processes.

In this paper we explore the possibility of using external secure elements, namely smart cards, to enhance the off-line security of commercial off- the-shelf (COTS) Android smartphones. The idea of using smart cards with smartphones is not completely new, but they are usually employed in solutions that need to be approved for RESTRICTED classification and above, and leverage customized devices in dedicated infrastructures. This approach defeats in part the purpose of using COTS products, and may be unnecessary for situations where budget is limited and data is mission sensitive, but not necessary classified, as in the use-case motivating this work. Here we present our findings on how different types of smart cards as Mifare NFC cards and Java Cards in both microSD and Dual format may interact with standard Android devices to enhance their security when not on-line. We conclude that smart cards can be a cost-effective way to mitigate some weaknesses of smartphones which can constitute a risk in tactical military scenarios, but compatibility challenges and device ownership models can limit their effective security.