Available user information rate capacities in battlespace network centric sensor operations

Network centric operations (NCO) has been dubbed the most significant revolution in military affairs (RMA) in the past 200 years. The promise of NCO is based on the notion that information sharing and connectivity is fundamental to the effectiveness of a combat force. This is due to the ability of a properly networked force to self-synchronise itself as it engages enemy forces. The information age combat model (IACM) is a popular representation of NCO. Previous research at modelling the IACM has so far focused solely at using agent-based modelling. That work produced significant contributions to the IACM literature. However, it has proven to be computationally expensive. IACM simulations must be sustainable as research into IACM evolves and more NCO complexities are introduced. This research will propose a discrete-event simulation (DES) approach to model the IACM. The paper will present the basis upon which DES was selected for this purpose and will illustrate how the DES approach can provide significant improvements in terms of the time and computational power needed to run IACM simulations.

Recent operations in Iraq and Afghanistan have confirmed that in order to achieve effective Network-Centric Operations (NCO), innovative enhancement to military decision-making is desired. Required are processes and computational models that support the decision-makers' experience while promoting high levels of shared situation awareness (SA)-not only in the context of the external operating environment, but internally aligning the decision makers' mental model with the intelligent software agents working on their behalf. Towards this end, the aim of this research is to enhance the decision-maker's perception, comprehension, and projection of the underlying knowledge space while improving shared human-agent SA. To accomplish this we extended R-CAST, an agent-based Recognition-Primed Decision (RPD) model developed at the Pennsylvania State University (PSU) with the capability to interactively visualize the knowledge space during execution. Presented are the early results of a recently completed knowledge visualization experiment where ROTC cadets from the PSU operated the visually-enhanced R-CAST on a command and control simulation.

A current focus in building military systems is the use of network based approaches. This is exemplified in the concepts of Network Centric Operations (NCO), Network Enabled Capabilities (NEC) or Network Based Defense (NBD). These concepts are, in part, inspired and motivated by the network based approaches that have revolutionized conducting business and operations in commercial domains across a wide spectrum of activities.Network centric systems in the commercial domain display a number of interesting capabilities. These included the means to integrate extremely large groups of users into effective systems‐of‐systems with time constants measured on the order of hours/days. The basic network centric enablers used in these systems fall into several major categories.This paper examines several high level architectures used in network centric operations for a number of non‐military network based systems; a ‘bricks and mortar’ retailer, on‐line ‘eCommerce’ businesses, and in software development. This examination is done by means of a literature survey and focuses on the interaction patterns that the systems must support, important capabilities the systems provide and important architectural enablers.

: The GIESim project was a simulation development program to define, design and implement a Modeling and Simulation (M&S) framework for the Global Information Enterprise (GIE). Within the GIESim framework users will be able to execute, via a common interface, multiple communications and network M&S tools to most effectively and efficiently analyze candidate communications architectures and technologies. GIESim can interface with other M&S tools (e.g., force-level simulations and detailed hardware system models) to provide the appropriate level of M&S fidelity and processing speed for the broad spectrum of M&S tasks. The GIESim user base will span from advanced technology researchers to communications network architects to mission planners. In FY04, the GIESim capabilities were merged into the Joint Semi-Automated Forces (JSAF) simulation in AFRL Rome in conjunction with the JSB-RD team. The central theme for the FY04 GIESim/JSB-RD merger was to add communications modeling capabilities to JSAF by interfacing GIESim communication modeling capabilities for faster and easier design, development and execution of GIESim simulations. This work resulted in the successful merger of GIESim/JSB-RD software, and the team can now demonstrate the addition of JTIDS tactical communications to JSAF using a modified version of the JTIDS simulation built by PSI. With the advent of this merger, JSAF now has tactical communications to support critical Network Centric Operations (NCO) and Warfare (NOW) needed for the future evolution of the Joint Enterprise including the AF C2 Constellation Net, Army/USMC LandWarNet, and the Navy/USMC FORCENet.

The advent of network technologies offers huge potential improvement in the useful information available to command and control (C/sup 2/) warfighter participants in both hostile battlefield and peacekeeping situations. In this paper, the force template concept is shown as a powerful element of the solution to these integration requirements. The evolving joint battlespace infosphere (JBI) and its application in the insertion of embedded infosphere software technology (IEIST) environment is discussed. This discussion focuses on how IEIST has adapted the evolving JBI force template concept to satisfy the needs inherent in integrating individual tactical platforms into network centric operations. The JBI force template concept and the IEIST force template implementation are compared and contrasted. The underlying strength of each in solving the integration of the warfighter with new sources of information available from infospheres such as the JBI is shown. The ultimate result of this integration is a more lethal and less vulnerable warfighter who knows the enemy's deployment and intent as it unfolds.

As requirements for communication navigation surveillance/air traffic management (CNS/ATM) and network centric operations (NCO) continue to become prevalent in military avionics systems, application of commercial real-time operating system (RTOS) products that support time and space partitioning are getting increased attention as tools for mitigating costs associated with safety and security certification. Isolation in time and space allows for multiple hazard levels to be independently assessed on the same processor. It also provides the necessary robustness for data of differing security levels to coexist as well, supporting a multiple independent level security (MILS) environment. Boeing under contract to Air Force Research Laboratory (AFRL) Information Directorate conducted a study that focused on the development and application of partitioned RTOS products. The target of the study was an example monolithic (single time/space) operational flight program (OFP) that was to be partitioned on a commercially available RTOS product and demonstrated in a Boeing systems integration lab. The end system consisted of three partitions: (1) an input/output (I/O) partition, (2) a navigation partition, (3) and the remaining components of the OFP. Anomalous behavior generated during the decoupling (partitioning) of computer software components (CSCs) often arises due to incorrect interpretation of syntactic, semantic, and contextual (temporal) elements. This is especially true during the decomposition into multiple time/spaces of software that was originally designed and tested within a single time/space. Generally syntactic errors are identified during the compilation portion of building a program, semantic errors identified during unit-level testing, and temporal errors identified during high-level integration. Since high-level integration typically relies on the concurrent execution of large amounts of code and more than one execution thread, it is this temporal error that proves to be the most difficult to identify and fix. To save development time and to reduce errors during execution, Boeing sought to identify where problems manifested by component decomposition might arise. A partitioning whitepaper was generated to proactively identify an approach for accomplishing the partitioning with minimal errors. Early in the whitepaper generation it was realized that a capability for the consistent and methodical analysis of disparate software interfaces needed to be developed. This capability essentially evolved into a taxonomy of behaviors of software interfaces within an Ada programming environment. This taxonomy focused on the syntax, semantics, and context of computer software interfaces in general. Additional emphasis was placed on how program units are related temporally since it was believed that the most difficult errors introduced by partitioning would be related to the temporal differentiation of the components imposed by the partition schedule. To represent this taxonomy, an XML schema was generated to capture the details necessary for a formal representation. Applying an XML schema was a useful method for capturing this detail since it provided a basis for application of future tools in the analysis of these interfaces. This paper is a product of that original partitioning whitepaper. It describes the original motivation for the study, the details and application of the taxonomy, and a comparison of the original ideas in the whitepaper versus the actual partitioned OFP result

Scenarios play an important role in driving the research agenda for programs focused on improving effectiveness in network centric operations. Several excellent scenarios such as Binni (www.binni.org) have played a key role in motivating research projects. However, as the geopolitical situation in the world has evolved, several new factors have become prominent that require the creation of a new scenario. This paper presents a new scenario for coalition operations that was developed to drive the research in the International Technology Alliance program, a multi-disciplinary multi-year program between the US and UK

This paper presents an industry-unique approach and improved model-based engineering practices for software reliant aircraft systems aligned with the Future Airborne Capability Environment (FACE™) open system technical reference architecture. A lifecycle toolset is described which fuses systems and software modeling and simulation (M&S) capabilities, modular open system architectures (MOSA), and device and sensor integration techniques into a single package to enable rapid design, development, verification, certification, and deployment of interoperable, platform portable, embedded mission-critical safety-critical avionic systems. TES' MBSE lifecycle toolset, AWESUM™, supports system architecture and virtual integration (SAVI) of cyber-physical system (CPS) assets, and evaluation of these platform assets through simulated mission rehearsals in a network-centric collaborative virtual environment. The result is improved systems product. The toolset has been demonstrated to several aviation-focused communities including the American Helicopter Society International (AHS), the Association of Old Crows (AOC), the FACE Consortium, and the US Army's Aviation and Missile Research Development and Engineering Center (AMRDEC), with favorable response. TES demonstrated a virtual simulation of realistically modeled and simulated multiple dissimilar aircraft platform systems conducting network centric operations (NCO). With the goal of improving flight-safety and enhancing the situational awareness (SA) of the battle-space, virtual missions were executed showing the inter-operations of cyber-physical system (CPS) assets and capabilities from reusable FACE-aligned applications. The simulated battle-space was composed of device-configured simulated flight models of both manned and unmanned rotorcraft platforms operating within a virtual environment of real-world terrain data. The environment included simulated threats and obstacles used to stimulate platform devices that report detections and produce alerts for own-ship flight mishap avoidance. These detections were then packaged into communications messages (VMF) and shared off-platform via NCO to the common operating picture (COP) to enhance the SA operations of the battle space flight group. After a decade of development and use supporting US Army military common software programs for the PM-AME and AMRDEC, TES is now making its industry-unique approach and model-based airworthy systems/software lifecycle product line available to industry. The MBSE lifecycle toolset product suite, referred to as AWESUM™ for AirWorthy Engineering Systems Unified Modeling, is a comprehensive model-based environment aligned to DO-178C, DO-331, AC 20-148, AR 7062, and FACE™. The AWESUM™ tool suite is currently supporting the US Army's Joint Common Architecture project, a model-based avionics architecture for the Joint Multi-Role family of future vertical lift platforms, and two other FACE-aligned US Army Aviation programs within the military communications and aircraft survivability domains. This is TES-SAVi's first publication and presentation to the IEEE. While we have applied our capabilities to the Military Aviation domain, these capabilities can be effectively applied to Aerospace and other domains.

Underwater acoustic channels usually suffer from the extended multipath propagation which causes inter symbol interference (ISI). At the receiving end, serious ISI would result in the decrease of the reliability of underwater acoustic communication systems. In this paper, Turbo equalization is applied to increase the reliability of communication systems. The realization of the channel equalizer in Turbo equalization is the linear minimum mean-square error (MMSE) estimate. To avoid performance loss, Turbo equalization and factor graph are combined together which provides a full-window method. Moreover, a modified extrinsic information feedback mechanism of turbo equalization is proposed. The reliability of communication systems is further enhanced by using this mechanism. Simulation results show that the proposed algorithm performs well with low complexity. This demonstrates the potential of the suggested algorithm in practice.

This paper is concerned with the microgrid communication systems and their impact on the microgrid control system. Regardless of the control structure, a microgrid cannot exist without a communication system. An efficient and reliable communication network ensures the possibility of implementing a secure, durable and cost-effective microgrid. The configuration of the communication network depends on many factors, like the structure of the microgrid, the control objectives, the implementation costs, the maintenance costs, etc. In the case of centralized control, all relevant data from the entire system is collected and processed in a single controller. The failure of a communication link in this central controller may cause the entire microgrid to fail. Therefore, the existence of a robust and reliable communication system is vital and the creation of redundant communication links is also recommended. The situation is different in the case of decentralized control, where communication is limited to local controllers, but this leads to limited performance, therefore it is preferable for such microgrids to have at least a very basic communication system composed of simple and inexpensive communication network. In the case of distributed control, each subsystem has its own local controller (LC) with the ability to communicate with other controllers for the purpose of exchanging information. Thus, the most advantageous communication network architecture is a hybrid one that consists of a combination of centralized and decentralized control methods.

Li-Fi (light-fidelity) considers a new technology in the wireless communication domain that operates light for transmission free space; the end-user has employed Visible Light Communication based on Light Emitting Diodes. This study aims to investigate the performance of Li-Fi to transmit data like video and pictures using different data rates under atmospheric turbulence such as rain and dust that affect FSO, therefore it affects at end-user and verifies the reliability of the Visible Light Communication (VLC) system sending data at high-speed data transmission. The systems are simulated by Optisystem V 18; the proposed system is built as a VLC system linked with fiber optic and free space optic channels to transmit various video sizes and an image using data rates of about 100 Mbps and 600 Mbps, and 1 Gbps over a lengthy distance under different weather, System was estimated in phrases of bit error rate, quality factor, power of signal, signal to noise ratio, and variation in angles. Despite the harsh environmental conditions imposed on the communication network, VLC has proven its ability to transmit high-speed data transmission for user's requirement.

With the development of digital instrument and control technology for nuclear power plants in recent decades, communication networks have become an important part of safety digital control systems, which takes charge in data exchange between the various sub-systems, and extremely impact on the reliability and safety of the entire I&C system. Traditional communication systems where some special features, such as reliability, safety, real-time, certainty, and independence are not strictly required are various illustrated. However, how to implement a communication system in a safety I&C system is rarely stated in current research. In this research, a reliable safety communication system applied in nuclear power plants is designed and analyzed. The five key characteristics of nuclear safety communication networks are explained, followed by explanation of how to achieve these characteristics. The analysis and verification of the designed system are also stated in this paper, which contributes to proving that the designed nuclear safety communication system could applied in the nuclear power plants.

IP over WDM has emerged as a winning network architecture to facilitate today's IP centric Internet. Although the total amount of bandwidth demands keeps increasing, there still exists a huge gap between the increasing full-wavelength capacity and the existing low-rate IP traffic. Efficiently grooming low-rate traffic stream to high-capacity lightpaths helps to alleviate the bandwidth mismatch, effectively improve the network resource utilization, and reduce the overall network cost. In this paper, we study traffic grooming problem in IP over WDM framework. The problem of minimizing the total number of transmitters and receivers in the networks is formulated as an integer linear programming (ILP) optimization problem. The ILP formulation produces optimal solutions for static traffic demands. However, applying the ILP solution to large and realistic networks is not practical due to its prohibitively large computation time. We therefore develop a heuristic algorithm, namely traffic aggregation algorithm. A significant improvement on wavelength utilization is observed in our experiments when we use our traffic aggregation algorithm. I. INTRODUCTION The popularity of the Internet and Internet protocol (IP)- based Intranet is promising enormous growth in data traffic originating from hosts that are IP endpoints. This growth is being fueled by various applications such as those driven by World-Wide-Web (WWW) and by the indirect impact of increased computing power and storage capacity at the end systems. The advent of new services with increasing intelligence and the corresponding bandwidth demands are further adding to the traffic growth. New access technologies such as Asymmetric Digital Subscriber Line (ADSL), High- bit-rate Digital Subscriber Line (HDSL), and fiber to the home (FTTH) would remove the access bottlenecks and enforce an even faster growth of demand on the backbone network. These changing trends have led to a fundamental shift in traffic patterns and the traffic is mostly due to data communications. In the past, the amount of data traffic on carrier networks was smaller than the voice-centric traffic. Therefore, the carrier networks were designed to primarily support voice traffic, and the data traffic was transmitted using the voice channels. Now, the core networks are being designed primarily for data traffic with voice support at the edges. The voice can be carried in the core networks using voice-over-IP or similar paradigms. To meet these growing demands, WDM will continue to emerge as a dominating trend for use in backbone networks. The research reported in this paper is funded in part by the National Science Foundation under grant ANI-0087746, grant ANI-0434872 and grant ANI- 0323374. Architectures will include to satisfy the need for better quality of service (QoS), protection, and availability guarantees in IP networks. WDM significantly increases the fiber capacity utilization by dividing the available bandwidth into non-overlapping wavelength channels, supporting connections between the two end nodes by establishing an all-optical channel, namely lightpath, which allows use of different formats, bit-rates, and protocol transparency. At the same time, most network designers believe that IP is going to be the common traffic convergence layer in communication networks. Consequently, IP over WDM has been envisioned as the winning combination of the network architecture.

The authors present line-coding methods that reduce the effects of dispersion-induced intersymbol interference (ISI) in high-speed (4 to 8 Gb/s) data transmission over direct-detection single-mode optical fibers. In addition to their use for synchronization purposes, line codes can be designed to eliminate certain worst-case patterns that would otherwise preclude reliable data transmission at very high rates. The authors study the use of these codes with directly modulated 1.55 mu m wavelength DFB (distributed feedback) lasers using conventional fiber (dispersion minimum at 1.3 mu m). Performance is quantified in terms of eye opening at the same information rate (which does not usually correspond to the same clock rate due to code overhead), normalized by any increased noise bandwidth. Examples of simple line codes (with symbol-by-symbol detection and feedback-free decoders) that significantly improve eye opening and thereby increase noise margins are given. The two examples presented at 4 Gb/s and 8 Gb/s realize respective coding gains of 1.65 dB and 5 dB over uncoded systems operating at the same data (information) rate. >

Accurate, dynamic rate selection is considered a hard problem in stream switching video applications over Internet Protocol. Not only the feedback delay but also the unawareness about the dynamics of the underlying HTTP/TCP transport layer require streaming applications to implement huge receiver buffers in the order of tens of seconds so as to maintain continuous video rendering with acceptable quality and bandwidth utilization. In order to achieve low-latency adaptive video streaming with a buffering delay as low as the chunk size, we present a streaming architecture under the implementation of media transport with predictably reliable transport and delay-based congestion control. A key component of our solution is a server-side simulation of the streaming client's buffer, which provides low-delay feedback for the video rate selection. The receiver buffer is being controlled via an open-loop synchronization mechanism relying on a reference clock that is transmitted within the media packets. We demonstrate the performance of our approach by evaluating the stability of the receiver buffer under low-latency and highdefinition adaptive video streaming with variable bit rate encoding over an emulated wide area network link.