Routing is a critical issue in MANET and therefore, this is the focus of this paper, along with the performance analysis of its routing protocols. In this paper the performance of four MANET routing protocols (AODV, DSR, OLSR and GRP) are compared. To evaluate and validate the performance of these protocols, a feasibility study in the form of simulations were carried out. In these experiments, ...

Differentiated Service Model (DiffServ) is currently a popular research topic as a low-cost method to bring QoS to today’s Internet backbone network. Simulation is the best way to study DiffServ before deploying it to the real Internet. In this paper, we introduce the techniques and methodologies that we used to design and implement DiffServ-enabled (DS-enabled) routers by using OPNET. We have ...

In OFDM-based IEEE 802.11 Wireless LANs, adapting the modulation type per sub-carrier to the frequency selectivity of the wireless channel leads to significant performance improvements. To integrate adaptive modulation into IEEE 802.11a/g networks, some minor modifications to the standard are needed in order to acquire the subcarrier gains and signalize the modulation assignments (on a per-pack...

Queuing disciplines have now become the subject of intensive discussion in network field. There are several queuing disciplines that claim best performance. In this paper, we evaluate a hypothetical network topology based on multi-class traffic approach. Multi-class traffic provides for aggregate traffic to be classified and conditioned at the edge of the network routers on the basis of perform...

Mobile Ad hoc Networks (MANET) are wireless networks without an infrastructure, which are usually set up on a temporary basis to serve a particular purpose within a specific period of time. An efficient routing protocol for MANET has become a necessary and important issue to be considered before deploying any mobile network. This paper presents a comparison among the reactive routing protocols:...

–Very large scale integration of complex circuits on to a smaller chip demands for the evolution of high speed computer networks. The traditional wired network constraints like mobility and expensive cabling. But wireless communication is a flexible data communication system implemented as an extension to or as an alternative for wired communication. The bandwidth and the services provided by t...

In order to improve the control overhead and to achieve the reliable data transmission in the patient monitoring system based on ZigBee, here the concentration is given on the comparative performance evaluation of different routing algorithm in a wireless body area network (WBAN) using the OPNET simulation tools. WBAN contains the number of wireless mobile nodes forming an unpredictable topolog...

In this work we present the results of a comparative study between two well-known network simulators: ns-2 and OPNET Modeler. In particular, we focus on a performance evaluation of the IEEE 802.11e technology on Mobile Ad-hoc Networks (MANETs) in both stationary and mobile scenarios. The paper describes the tested scenarios in detail, and discusses simulation results obtained with OPNET Modeler...

This paper presents and validates through simulation an analytical model for multihop connections in AMR systems (Automatic Meter Reading). The model is based on a Markov Chain and has been validated with a Monte Carlo Simulation based on OPNET Modeler in order to obtain a verification of the explicit formulas calculated from analytical model. The model is applied to the AMR case where the norm...

Over the past few years, many high performance ATM switches have been proposed. The majority of these switches have high performances but also have very high hardware complexities. Therefore, there is a need for switch designs with lower complexity and high performance. The authors are considering using the folded hypercube (FHC) as a new infrastructure for ATM switches. Before the FHC is modif...