Abstract The inception of multimedia applications, the Mobile Adhoc Networks has created multi-disciplinary challenges for researchers in the field of network engineering. These applications on one hand consume extensive bandwidth and battery power and on the other hand require special treatment by the network entities to experience minimum delay by the traffic they generate. Due to some inherited limitations in MANET... The inception of multimedia applications, the Mobile Adhoc Networks has created multi-disciplinary challenges for researchers in the field of network engineering. These applications on one hand consume extensive bandwidth and battery power and on the other hand require special treatment by the network entities to experience minimum delay by the traffic they generate. Due to some inherited limitations in MANET like low processing capabilities and limited transmission power, the multimedia traffic will require careful attention to route along the network from the source to destination. The legacy Dynamic Source Routing (DSR) protocol was designed in 1994 for simple data transmission. For transmission of multimedia traffic over DSR, many newer schemes are proposed in the last decade to meet the quality of service requirements. However the proposed scheme in this paper utilizes the Enhanced Distributed Channel Access (EDCA) based medium access mechanism as defined in IEEE 802.11E standard. The EDCA works on the principle of traffic prioritization into four access categories, thus allowing higher priority traffic more chances to access medium and transmit on the network. The proposed scheme uses cross layer technique to take EDCA parameters from the MAC layer on real time and calculate routing metric. OPNET Modeler is used to implement the scheme and evaluate results. The performance comparison shows the significance of the proposed scheme over the standard DSR routing. Read More Read Less

Abstract A new learning algorithm suited for training multilayered neural network is proposed that we have named hybrid is hereby introduced. With this algorithm the weights of the hidden layer are adjusted using the Kohonen algorithm. While the weights of the output layer are trained using a gradient descent method with adaptive learning parameter based Lyapunov function. The effectiveness of the... A new learning algorithm suited for training multilayered neural network is proposed that we have named hybrid is hereby introduced. With this algorithm the weights of the hidden layer are adjusted using the Kohonen algorithm. While the weights of the output layer are trained using a gradient descent method with adaptive learning parameter based Lyapunov function. The effectiveness of the proposed approach is shown by the simulation results. Read More Read Less

Abstract The goal of this paper is to implement and establish an interconnection between Asterisk server and phone networks in general and mobile networks in particular. The arrival of new generations of phones that are equipped with Android system facilitates this project. More than the main goal is to remove the cost of internal calls using asterisk with the possibility to... The goal of this paper is to implement and establish an interconnection between Asterisk server and phone networks in general and mobile networks in particular. The arrival of new generations of phones that are equipped with Android system facilitates this project. More than the main goal is to remove the cost of internal calls using asterisk with the possibility to call to the external network : PSTN and GSM. Read More Read Less

Abstract The electromagnetic noise in large cities is inevitable, it causes high delays and worsens the throughput due to data distortion. To reduce the impact of noise on the performances of IEEE 802.11 networks, we propose an enhancement of the IEEE 802.11 RTS/CTS scheme to recognize the reason of a transmission failure (collision or noise errors), thus the data packet is... The electromagnetic noise in large cities is inevitable, it causes high delays and worsens the throughput due to data distortion. To reduce the impact of noise on the performances of IEEE 802.11 networks, we propose an enhancement of the IEEE 802.11 RTS/CTS scheme to recognize the reason of a transmission failure (collision or noise errors), thus the data packet is immediately retransmitted with zero-waiting backoff time if a failure happens due to distortion by noise. This retransmission continues until the data packet is successfully transmitted or dropped when the number of packet transmission attempts reaches its limit. The proposed performance evaluation and comparison have been done under our own network simulator tool. So, we have analyzed the overall throughput of the IEEE 802.11 network. Read More Read Less

Abstract One of the major issues for Heterogeneous Wireless Access Networks (HWAN) or Next Generation IP/MPLS Wireless Network (NGWN) is integrating the different wireless access technologies (e.g. GSM, GPRS, EDGE, UMTS, WiMAX, WLAN, etc…) into a common platform. This integration should transparently provide mobile users unified and continuous services, including seamless handoff and real-time support of QoS. However, a real-time support... One of the major issues for Heterogeneous Wireless Access Networks (HWAN) or Next Generation IP/MPLS Wireless Network (NGWN) is integrating the different wireless access technologies (e.g. GSM, GPRS, EDGE, UMTS, WiMAX, WLAN, etc…) into a common platform. This integration should transparently provide mobile users unified and continuous services, including seamless handoff and real-time support of QoS. However, a real-time support of End-to-End QoS, in HWAN, is a challenging task that requires mapping of related messages as well as their associated attributes and parameters across all networks. In this paper, we present a novel method for mapping these messages and their attributes across UMTS, WiMAX and IP-Diffserv/MPLS networks. Read More Read Less

Abstract A few years ago, the applications of WSN were rather interesting than a powerful technology. Nowadays, this technology attracts still more and more scientific audience. This paper proposes a novel case study of routing algorithm for large scale wireless sensor network (WSN) which aims to prolong the network lifetime as long as possible. Our approach focuses on optimizing routing protocol... A few years ago, the applications of WSN were rather interesting than a powerful technology. Nowadays, this technology attracts still more and more scientific audience. This paper proposes a novel case study of routing algorithm for large scale wireless sensor network (WSN) which aims to prolong the network lifetime as long as possible. Our approach focuses on optimizing routing protocol in WSN without losing information on mobile environment and an active notwork. We want also improve the possibility to prolong live-time of node and their energy. We will make a study to prove the feasibility of the scalability for our proposed model. When comparing result, we will propose a solution to make ability to this model. Read More Read Less