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This document outlines and demonstrates an approach to generating a synthetic email dataset using the Enron email dataset as a reference and the Synthetic Transaction Data Generator (STDG) simulator application. With statistical measures extracted from the Enron dataset, we generate synthetic email threads within the confines of a fictitious corporate structure. Our approach extrapolates the network structure of who communicates with whom and the timing of these communications, but it ignores semantic content. To this end, we first harvest the statistical network and temporal features of the Enron reference dataset. With these features, we use the agent-based STDG application to stochastically generate corporations of arbitrary sizes and email transactions within the corporations over a specified time period. We evaluate our methodology by comparing features of the synthetically-generated datasets with those of the reference dataset.

In contrast to the interference avoidance paradigm that conventional wireless communication systems follow, the DARPA Interference Multiple Access (DIMA) Communications program intentionally structures multiple-access interference to enable high-capacity, low-latency, spread spectrum communications. The systempsilas adaptive multi-user detection (MUD) receiver algorithms enable the transmission of multiple data streams in the same time and frequency channel without need for centralized control of synchronization or power levels. This paper focuses on the DIMA system level implementation of the prototype radio network, along with the results from both non-real-time testing and real-time performance characterization efforts. Extensive simulations and non-real-time over-the-air testing helped to drive the design of a real-time MUD receiver implemented on a single FPGA. The Media Access Control Layer, implemented on a General Purpose Processor (GPP), facilitates intentional interference through a defined frame structure that also enables distributed synchronization and scheduling. During the real-time performance characterization period, the DIMA prototype network demonstrated 3.5 times the spectral efficiency of comparable 802.11 ad-hoc systems at low signal to noise ratios (SNRs). DIMA demonstrated up to 11x reductions in latency jitter in the same comparison. These gains can be leveraged in future military applications to provide increased capabilities and improved performance to the war fighter.

The implementation of network centric warfare on the battlefield has driven the growing demand for high capacity warfighter communication systems. Although new high capacity SATCOM systems such as WGS are being introduced in the near term, these systems use the interference avoidance paradigm, which fundamentally limits overall network performance. This paper introduces a new wireless networking paradigm called Interference Multiple Access (IMA), developed under the auspices of DARPA. The interference multiple access paradigm exploits multi-access interference to enable revolutionary improvements in wireless communication capacity and latency without the need for infrastructure, coordination, or spectrum preplanning. Simulation and over-the-air test results suggest that greater than 3X increases in network throughput (especially in low SNR scenarios) can be achieved over traditional contention and scheduled-based spectrum access approaches when applied to WIN-T NCW terminals communicating in a mesh topology over the WGS constellation.

The advent of network coding promises to change many aspects of networking. Network coding moves away from the classical approach of networking, which treats networks as akin to physical transportation systems. We overview some of the main features of network coding that are most relevant to wireless networks. In particular, we discuss the fact that random distributed network coding is asymptotically optimal for wireless networks with and without packet erasures. These results are extremely general and allow packet loss correlation, such as may occur in fading wireless channels. The coded network lends itself, for multicast connections, to a cost optimization which not only outperforms traditional routing tree-based approaches, but also lends itself to a distributed implementation and to a dynamic implementation when changing conditions, such as mobility, arise. We illustrate the performance of such optimization methods for energy efficiency in wireless networks and propose some new directions for research in the area.

Current military operational effectiveness can degrade rapidly with increasing communications stresses such as heavy throughput and QoS demands from disadvantaged users exposed to severe channel impairments and communications threats. This paper proposes a distributed and agile radio resource management (RRM) system to maintain mission effectiveness even under significant communications stress. Agile RRM includes a well-coordinated cross-layer design with the introduction of new OSI layer features and interactions as well as methods to incorporate communications constraints and requirements in systems controlling mission planning and execution.