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Mobile communication systems are equipped with multiple network interfaces. Wireless Fidelity (WiFi) and 3rd Generation (3G) are the most widely implemented interfaces in the latest mobile communication devices and therefore being able to fulfil most of the computing aspects. Nowadays, most modern mobile devices suffer from the interoperability between the WiFi and 3G interfaces, each access technology...
We have considered various types of congestion control algorithms. Each congestion algorithm has its own advantages and it would vary from parameters to parameters. Random Early Detection (RED) is more focused on queue length and BLUE is care about loss of packets. In this paper we have found the problems with existing congestion control algorithms. We have tried to show their performance of RED,...
The paper envisages the network modeling of a wireless multicast network by approach of optimized joint MAC scheduling and network coding. A heuristic method of designing a network is achieved by scheduling algorithm which is based on network parameters such as interference free transmissions, and optimization of avoidable scheduling sets. We derive a joint linear optimization problem which is used...
In the development of advanced data acquisition, testing or telecommunication equipment, one often relies on modular off-the-shelf processor boards and I/O-boards that are being composed to a single distributed system. To support such architectures, the microTCA (micro Telecommunication Computing Architecture) offers standardized racks and standardized back panel communication protocols connecting...
Recent expansion of the computer networks has opened a possibility of explosive spread of computer viruses. Viral spreads that attack the end user or the nodes and hence the traffic on the network increases by self duplication and perpetuation. The net effect is, increase of senseless throughput spiraling, multiplication of load, and increased delay, leading to severe congestion and crash. Thus there...
Analytical models of the Distributed Coordination Function (DCF) have numerous applications in the performance analysis of IEEE 802.11 networks. The model proposed in this paper distinguishes itself from existing approaches in that it allows throughput, delay, and frame loss ratio analysis under both saturation and non-saturation network conditions. It combines the Markov chain and the queuing theory...
The behavior of Networked Embedded Systems (NES) is not only driven by network components but also by the surrounding environment. To verify the correct behavior of such systems, different tests should be performed under different environmental conditions. The complexity and expense of testing such systems in real environments leads us to propose a simulation-based approach to tackle this problem...
Rapid technological advances and innovations in the area of autonomous systems push the researchers towards autonomous networked systems with emphasis on Wireless Sensor Networks (WSNs). In WSN event-driven applications, it is critical to report the detected events in the area, resulting in sudden bursts of traffic due to occurrence of spatially-correlated or multiple events, causing loss of data...
In this paper we study the influence of Weighted Round Robin (WRR) scheduling algorithm frame size to the performance of Crosspoint Queued (CQ) crossbar switch. In order to show that throughput and cell delay can be adjusted with appropriate WRR frame size, we analyzed switch for different values of frame size and under the unbalanced bursty traffic. We show that WRR scheduling algorithm achieve throughput...
Since wireless sensor nodes are battery powered, the emphasis was on reducing the energy consumption of the sensor nodes. However, with the increase in real-time traffic requirements in wireless sensor nodes, network performance metrics are increasingly important. Nonetheless, most existing network performance studies were done via simulation, with few experimental studies performed on testbeds using...
In this paper, we study the problem of user pairing algorithms for uplink virtual multiple-input multiple-output (V-MIMO) networks, with Quality of Service (QoS) considered. After analyzing the transmission model and delay model, we propose a balanced QoS and proportional fair (B-QPF) algorithm of user pairing, which selects users depending on proportional fair (PF) criterion and the instantaneous...
Video streaming is the real time delivery process of video to the user's media player services. In multimedia streaming technique, the user can access data while it is being transferred. To meet the demand of providing high-quality of video streaming, it is important to design suitable QoS model. Hence, in this project, we designed around streaming services using an Internet topology on expected video...
In the past decades, cooperative communications technologies have gained significant attention in wireless networks. The cooperative scheme leads to longer transmission time which can considerably degrade the performance. Thus, there is always a tradeoff between saturation throughput and saturation delay. In order to obtain the optimal system performance, we utilize the cost function to tradeoff the...
Tremendous research effort has been made to reduce the idle time on the wireless medium of mobile adhoc network. Tradeoff among idle channel, collision and throughput was always a challenge. Hidden terminal problem creates collisions. On the other hand exposed terminal problem makes channel unnecessarily idle. Standard virtual carrier mechanism and many other alternative proposals for solving these...
By employing a relay station (RS) on the WiMAX networks, it offers an extended coverage and improved capacity over wireless broadband. However the mobile station (MS) such that connected to the RS has effect the system performance due to increase of the MS numbers. In WiMAX the base station (BS) adopts the centralized-based polling mode where the best way to guarantee the delay bound is by polling...
Routing in Wireless Mesh Network (WMN) is challenging because of unpredictable variations of wireless environments. Traditional mechanisms have been proved that the routing performance would get deteriorated and ideal metrics must be explored. Cross-layer based approaches for routing optimization have been paid more attention in the recent. Based on information obtaining from wireless channel conditions...
This paper presents, through simulation experiments, a performance study of both IEEE 802.11n aggregation methods: A-MPDU (Aggregated MAC Protocol Data Unit) and A-MSDU (Aggregated MAC Service Data Unit), considering scenarios of video streaming. The objectives of this article are: (i) investigate the quality of service achieved, (ii) show which of the two methods of aggregation (A-MPDU or A-MSDU)...
Wireless Mesh Networks (WMNs) extend the range of the IEEE 802.11 Wi-Fi beyond the one-hop range. This has made it an attractive research topic given the exponential growth in Wi-Fi portable devices. However, the multi-hop nature of WMNs creates many new challenges, primarily in the Medium Access Control (MAC) layer. Specifically, the IEEE 802.11 Medium Access Control (MAC) layer is designed for a...
In next generation wireless networks like WiMAX, a dynamic Call Admission Control (CAC) plays an important role to ensure Quality of Service (QoS) of existing users and to efficiently utilize network resources. We propose a predictive CAC namely Wireless Fair Intelligent Admission Control (WFIAC) that admits or rejects a new incoming connection base on resource availability and load in the network...
An airdropped meteorological parameters measurement network (AMPMN) is introduced in this paper. AMPMN with star topology is composed of two kinds of nodes, sensor nodes and one relay node, all equipped with nRF905 radio frequency (RF) modules. A three-layer protocol is built on nRF905 in terms of its configuration. The RF configuration parameters and the payloads formats are set to enable the implementation...
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