Tag Archive: 'opnet simulation'

Application Performance Analysis of Distributed File Systems under Cloud Computing Environment

The processing efficiency of data-intensive application on Hadoop with the general-purpose distributed file system such as Lustre, as the backend file system, is not clear. This paper focuses on the similarities and differences between Lustre and HDFS (Hadoop Distributed File System). We propose a Hadoop-Lustre platform and evaluate the performance differences of Lustre and HDFS […]

Non-Myopic Adaptive Route Planning in Uncertain Congestion Environments

We consider the problem of adaptively routing a fleet of cooperative vehicles within a road network in the presence of uncertain and dynamic congestion conditions. To tackle this problem, we first propose a Gaussian process dynamic congestion model that can effectively characterize both the dynamics and the uncertainty of congestion conditions. Our model is efficient and thus […]

Active queue management for congestion avoidance in multimedia streaming

Reducing the queue length and queuing delay in the buffer which in turn reduces congestion and latency in the network are of great importance for real-time video services. This paper proposes a congestion avoidance active queue management, tailored for scalable video coding (SVC). This distortion-constrained (DC) queue management mechanism maximally decreases the queue length and queuing delay […]

Reconfigurable body worn antenna for Bluetooth and WiMAX

The paper presents a frequency reconfigurable microstrip patch antenna printed on a textile substrate. It can be tuned by using active circuitry between Bluetooth and WiMAX operating at 2.4 GHz and 2.5 GHz frequency bands respectively. Indigo blue jeans having relative permittivity 1.68 with thickness 1 mm is used as a textile substrate. The frequency […]

Agent based State Estimation in Smart Distribution Grid

A novel agent based static state estimation strategy for a specific class of physical systems is proposed. Physical systems, (e.g. smart distribution grid) which are well modeled using decentralized measurements and distributed state-space formulations are considered. In such systems, sensor nodes acting as agents estimate only a subset of states, instead of evaluating local estimates […]

Performance Optimization of DCF-MAC Standard Using Enhanced RTS Threshold under Impact of IEEE 802.11n WLAN

Wireless Local Area Networks (WLANs) communication means gained widespread reception in recent years and widely used all over world due to its wireless fidelity feature with high data rates assets. With emerged multimedia application on wireless networks and the integration with other cellular networks, requires support for quality of service. In this paper, performance optimization […]

Improving system capacity based upon user-specific QoS for heterogeneous networks

This paper describes how user-specific QoS requirements may improve spectral utilization in heterogeneous networks. Throughput improvements of FTP (File Transfer Protocol) applications benefiting from the rate adaptation and MAC scheduling algorithms for video applications that incorporate user-specific QoS to improve system capacity are demonstrated. These improvements are achieved while user satisfaction for video applications, as […]

Impact of IPSec on Real Time applications in IPv6 and 6to4 Tunneled Migration Network

IPSec is the amalgam of protocols dispensing security in IP networks. It has been the rudimentary security component in IPv4 and IPv6 networks providing for data authentication, integrity and confidentiality. Earlier security was not embedded at the IP level however with emergence of large scale public and corporate internets, the user data became vulnerable to […]

A channel allocation method for IEEE802.19.1 coexistence service to mitigate interferences among heterogeneous wireless networks

IEEE 802.19.1 is the world first standard that specifies coexistence methods by means of exchanging messages between 802.19.1 coexistence system and wireless systems registered to the coexistence system. We propose a channel allocation mechanism for 802.19.1 management service. The mechanism mainly depends upon channel classification where the CM manages channel availability information based on TV […]

Research on dynamic routing algorithm of the combat collaboration communication network

The military communication system is the key element to make a victory in the battle. In general, the combat collaborative communication network is a multi-hop and autonomous system, which is composed by a group of mobile nodes with wireless communication ability. The network has some features such as no center, self-organizing, multi-hop routing and dynamic […]