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A collision free MAC protocol for energy saving in wireless ad hoc networks

2004

Abstract Wireless ad hoc networks represent a powerful tool for enabling wireless networking where temporary network connectivity is needed. However, a wide deployment of wireless ad hoc networks relies on system architectures that provide energetic optimization. This paper describes a preliminary proposal of a collision free MAC protocol able to minimize energy consumption. The algorithm has been developed starting from the theory of balanced incomplete block design (BIBD).

Better Result in Packet Loss and Saving Energy in Ad-Hoc Network by using Improved MAC Protocol

An Ad-Hoc network is a wireless, decentralized, dynamic network in which devices associate with each other in their link range, in which the basic 802.11 MAC protocol uses the Distributed Coordination Function (DCF) to share the media between various devices. But use of 802.11 MAC protocol in Ad-Hoc networks affected by different issues such as restricted power capacity, packet loss because of transmission error, various control traffic and failure to avoid packet collision. To solve these problems various protocols have been proposed. But we don't have any perfect protocol which can resolve the issues related to power management, packet collision and packet loss efficiently. In this research paper, we suggest a new protocol to adjust the upper & lower bounds for the contention window to decrease the number of collisions. As well as it proposes a power control scheme, triggered by the MAC layer to reduce the packet loss, energy wastage and decrease the number of collisions during transmission. The proposed MAC protocol is implemented and performance is compared with existing 802.11 MAC protocol. We computed the Packet Delivery Fraction(PDF), average End-to-End(e-e) delay, average throughput and packet loss in several conditions. We find proposed protocol is comparatively improved than the existing protocol.

Performance Analysis of Collision Avoidance MAC Protocol in Multi-Hop Wireless Ad-Hoc Network

International Journal of Network and Mobile Technologies, 2011

Performance analysis of 802.11Medium Access Control (MAC) protocol has been carried out either by means of simulation or by means of analytical models with simplified back-off rule assumptions. Binary Exponential Back-off (BEB) is the widely used back-off mechanism in many contention-based IEEE 802.11 MAC protocols for its simplicity and good performance, but it has drawbacks especially in multi-hop ad hoc network and some new back-off schemes such as Multiplicative Increase and Linear Decrease (MILD) and Double Increment Double Decrement (DIDD) were proposed. This paper, investigate the performance of collision avoidance MAC protocol in multi-hop wireless ad-hoc network by adopting MILD back-off mechanism. A three state Markov chain is used to model the channel states and node states. These models were used to derive the duration time, steady-state probabilities of the states of node and throughput of Mobile Ad-hoc NETwork (MANET). Simulation results show no matter the value of average number of neighbors , transmission range , and length of DATA frames , the throughput of MANET always achieves the maximum value at some point of persistent probability and also the throughput of a MANETs increases with increase in persistent probability which is influenced by the number of neighbors, transmission range and length of DATA frame. On the other hand the throughput decreases with increase in sensing range which is also influenced by the number of neighbors, transmission range and length of DATA frame.

Improved cross-layer cooperative MAC protocol for wireless ad hoc networks

Signal and Information Processing Association Annual Summit and Conference (APSIPA), 2014 Asia-Pacific, 2014

This paper considers the design of a cross-layer medium access control (MAC) protocol for wireless ad hoc cooperative networks. Specifically, we redesign the message exchange process of the MAC protocol previously proposed by Shan et al. By using a HRP signal with shorter length the proposed protocol can reduce the protocol overhead and thus improve the transmission reliability. We also propose to use only one HRP signal to resolve the collision among the helpers with the same cooperative rate. The proposed protocol achieves higher path throughput and lower end-to-end packet latency compared with that by Shan et al. and the traditional IEEE 802.11 MAC protocol.

An Improved MAC Protocol to Reduce Packet Loss and Energy Wastage in Ad-Hoc Networks

An Ad-Hoc network is a wireless, decentralized, dynamic network in which devices associate with each other in their link range, in which the basic 802.11 MAC protocol uses the Distributed Coordination Function (DCF) to share the media between various devices. But use of 802.11 MAC protocol in Ad-Hoc networks affected by different issues such as restricted power capacity, packet loss because of transmission error, various control traffic and failure to avoid packet collision. To solve these problems various protocols have been proposed. But we don’t have any perfect protocol which can resolve the issues related to power management, packet collision and packet loss efficiently. In this research paper, we suggest a new protocol to adjust the upper & lower bounds for the contention window to decrease the number of collisions. As well as it proposes a power control scheme, triggered by the MAC layer to reduce the packet loss, energy wastage and decrease the number of collisions during transmission. The proposed MAC protocol is implemented and performance is compared with existing 802.11 MAC protocol. We computed the Packet Delivery Fraction(PDF), average End-to-End(e-e) delay, average throughput and packet loss in several conditions. We find proposed protocol is comparatively improved than the existing protocol.

Mac Protocols in Mobile Ad Hoc Networks

International Journal of Advances in …, 2012

Mobile Ad hoc NETwork (MANET) is a wireless network of mobile nodes connected by wireless link without a central control. The Medium Access Control (MAC) protocol is one of the important issues in such network, thereby the presented paper will discuss the MAC protocol used in MANET depending on IEEE 802.11 standard which known as Distributed Coordination Function (DCF).However, the limitation of MANET is that, the collision increases with the rise of nodes number. Therefore paper study the MAC protocol using directional antennas to reduce the collisions, increase the range of transmission and largely reduce the interference between the directions. However, the main problem of using directional antennas is caused by frequent node mobility. So the movement plays a vital role in wireless Ad hoc networks to predict the location of MNs.

Modeling and Analysis of Collision Avoidance MAC Protocol in Multi-Hop Wireless Ad-Hoc Network

International Journal of Communication Networks and Information Security (IJCNIS), 2011

The absence of centralized administration, multi-hop transmission, and the nature of wireless channels pose many challenging research area in Mobile Ad hoc NETworks (MANETs). In this paper, a collision avoidance Medium Access Control (MAC) protocol was used for the modeling and analysis of multi-hop wireless ad hoc network, in which RTS/CTS/DATA/ACK handshake and Exponential Increase Exponential Decrease (EIED) back-off mechanism were adopted. A simple n-vertex undirected graph G(V, A) is used to model the topology of MANET while three-state Markov chain was used to model channel state and node state of MANET. Simulation results show that throughput increases with increase in persistent probability, sensing range and length of a DATA frame. Also throughput has a peak value at some point of the persistent probability, sensing range and length of a DATA frame, which is influenced by the number of nodes. In the other hand throughput increases along with the increase of transmission range for some values, then it start decreasing with increase in transmission range. Furthermore throughput decreases with increase in the number of nodes and back-off time. In order to validate the proposed models, a performance comparison of the throughput of existing model with the throughput of the proposed model by considering persistent probability, sensing range, transmission range, length of DATA transmission and back-off time was carried out. The overall results show that the proposed model achieve better throughput than the existing model.

Mobile Ad Hoc Network for Collision Avoidance in Mac Protocol Using Logarithmic

The main application of the VANETS is to provide the routing between the vehicles. During the transmission of data collisions may occur. To avoid the collision problems the Binary Exponential Back off (BEB) Algorithm is proposed. BEB results in a high delay in message transmission, collisions and ultimately wasting the limited accessible data transfer capacity. As every hub needs to get medium access before transmitting a message, in thick systems, the crash likelihood in the Media Access Control (MAC) layer gets to be high when a poor back off calculation is utilized. The Logarithmic calculation proposes some improvements to the back off algorithms that aim to efficiently use the channel and to reduce collisions. The algorithm under study is based on changing the incremental behavior of the back off value. This paper carries out a deeper study and analysis of the logarithmic back off algorithm that uses logarithmic increment instead of exponential extension of window size to eliminate the degrading effect of random number distribution.

ADVANCED AND EFFICIENT MAC PROTOCOL FOR MOBILE AD-HOC NETWORK.

International Journal of Advanced Research (IJAR), 2018

Mobile Ad-hoc Network (MANET) is an autonomous system of mobile nodes connected by wireless links. The nodes are free to move about and organize themselves into a network. These nodes change position frequently. To accommodate the changing topology special routing algorithms are needed. The Media Access Control (MAC) data communication protocol sub-layer provides addressing and channel access control mechanisms that make it possible for network nodes to access common wireless channel through distributed coordination function (DCF).This work proposes a new power controlled MAC protocol based on IEEE 802.11. Network Simulator 2 (NS2) has been used for simulation. It saves considerable amount of power and achieves the performance matching with that of IEEE 802.11