The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
OTC, together with the JTRS JPEO and PEO-I MSO, funded a Small Business Innovative Research (SBIR) Phase 2.5 Technology Transition effort, with SNT as the contractor, to develop the JTRS Network Emulator (JNE) to support GMR LUT and MOTE test activities. The accuracy of the JNE, to a large extent, depends upon the accuracy of its constituent models. Consequently, OTC funded an effort to verify and...
IPTV will be one of the main drivers of network innovation in the near future. Its bandwidth demands, especially if combined with HDTV, require smart algorithms for content distribution. One approach that is currently discussed intensively is Application Layer Multicast (ALM), which allows to scale to large node numbers by incorporating the resources of participating peers. In addition, locality-aware...
In this work, we carry out a comparison evaluation for mobile and static sensor nodes in Wireless Sensor Networks (WSNs) using TwoRayGround propagation model and different protocols. We consider packet-loss and delay metrics to evaluate the performance of WSN. The simulation results have shown that for WSN with mobile sensor nodes, the delay is better than static sensor nodes. In case of static sensor...
Major challenge for TCP is to keep up the new and modern generation in communications networks such as networks with large bandwidth and long delay because when TCP applies on next generation networks will suffer from degradation in performance. The reason behind this shortcoming in performance is due to the congestion control mechanisms supported by TCP variants where these mechanisms depending on...
The 2.4 GHz band of the IEEE 802.15.4 specifies low rate transmission of 250 kbps. Because of the low bandwidth, it is not easy to implement Voice over Sensor Networks (VoSN) even peer to peer voice communication. In this paper, we implement VoSN using non beacon-enabled mode to achieve high utilization of bandwidth. As a result, peer to peer full-duplex voice communication in the long distance and...
This paper investigates out synchronization with identical topologies connection and the adaptive synchronization with nonidentical topologies connection between two nonlinearly delay-coupled complex networks with the bidirectional actions. A new Lyapunov-Krasovskii functional is constructed for the two complex networks, and the S-procedure is employed to handle the nonlinearities and identical topologies...
Wireless mesh networks (WMN) are efficient and low cost solutions for the deployment of broadband access in various environments. To support real-time applications such as multimedia and emergency services, WMNs must provide quality of service (QoS) guarantees and QoS continuity protection. While the capacity of single radio WMNs may severely limit the QoS for such traffic, multiradio WMNs can overcome...
In these last years the demand for personal and ubiquitous communication has raised at a tremendous rate. Mobile services, which are nowadays typically offered based on location and context, suffer from various 3G shortcomings, and many data providers are looking for innovative solutions offering a carrier-independent, location-based, and cheaper than 3G data distribution. The deployment of a Delay...
Problems related to network coding for acyclic, instantaneous networks (where the edges of the acyclic graph representing the network are assumed to have zero-delay) have been extensively dealt with in the recent past. The most prominent of these problems include (a) the existence of network codes that achieve maximum rate of transmission, (b) efficient network code constructions, and (c) field size...
QoS routing is used for finding feasible paths that satisfy simultaneously multiple constraints and it is a NP-complete problem. The difficulty of solving such problems increases in the hierarchical context, where aggregation techniques influence the path computation process. This paper offers a solution for hierarchical QoS routing by introducing the protocol called Multi-constrained Macro-routing...
Network coding is an emerging and powerful solution that can significantly improve the throughput and power efficiency of wireless networks by allowing mixing of various traffic flows into a single packet. However, when network coding is applied, a packet will have to wait to be network-coded with others, which may result on large delay and packet-loss rate. It will bring negative influence to the...
Technology of wireless sensor networks has grown thanks to technological developments in different areas related to microelectronics. However, to become truly ubiquitous, these networks must overcome a number of challenges such as resource constraints (energy, memory, etc.), quality of service (bounded transmission delays), etc. It follows that the energy conservation and latency minimization are...
Resilience is the ability of a network to provide acceptable service in the presence of challenges to normal operations. With increasing significance of resilience in modern communications infrastructure and services, there is a need for rigorous quantitative evaluation of resilience. In this paper, we present a framework to quantify resilience between any two layers in the network stack. Resilience...
In delay tolerant networks (DTNs), the lack of continuous connectivity, network partitioning, and long delays make design of network protocols very challenging. Previous DTN research mainly focuses on routing and information propagation. However, with large number of wireless devices' participation, how to maintain efficient and dynamic topology of the DTN becomes crucial. In this paper, we study...
We analyze the problem of buffer sizing for TCP flows in 802.11-based Wireless Mesh Networks. Our objective is to maintain high network utilization while providing low queueing delays. The problem is complicated by the time-varying capacity of the wireless channel as well as the random access mechanism of 802.11 MAC protocol. While arbitrarily large buffers can maintain high network utilization, this...
In this study, the effects of time slot parameters on the performance of time domain switching optical burst switched networks (OBS) are studied. We investigate OBS networks where all core nodes are able to receive and send data. Network throughput is reduced when bursts are not able to secure necessary time slots for their transmission due to heavy contention at the core networks and lack of proper...
Mutli-domain monitoring aims at guaranteeing QoS for services crossing several domains. It is often desirable to perform global monitoring to guarantee end-to-end QoS for services across domains and to reduce the monitoring cost. However, global monitoring might be infeasible due to confidentiality constraints. The alternative solution is to perform per-domain monitoring. In this work, we propose...
Today's premium vehicles are some of the most complex consumer goods-featuring a large number of different functionalities. These functionalities are being implemented by numerous Electronic Control Units (ECUs), which are often interconnected with CAN, FlexRay, LIN, and MOST. However, some car models already use Ethernet for high bandwidth applications, like diagnosis, flash update, and multimedia...
Mobile Ad-hoc Networks (MANETs) involve the establishment of wireless connections between mobile nodes, and can dynamically extend the coverage area of wireless local area networks (LAN). For MANETs that use a single channel, the communication performance decreases due to interferences between nodes when frames are being relayed. In this paper, we propose a priority control scheme based on neighbor...
With the promotion of IP packet applying to distributed communications network, the capacity of self-organizing network will be an urgent need. The single-channel single-interface model does not meet the requirements of complex systems. In this paper, we build a distributed network topology which refers to features of military communications network, and implement M-ZRP which supports multi-channel...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.