The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The performance evaluation of wireless networks for industrial applications represents a relevant issue for the scientific community. One of the most important aspects of these activities is concerned with the validation of the theoretical models derived from accurate analysis of the protocols employed by the networks. In this paper we focus on a typical industrial application of the IEEE 802.11 wireless...
Energy-efficiency in underwater networks is a key issue that affects all aspects of network design, from hardware to protocols and applications. In this paper we analyze the impact of node density on the energy consumption in transmission, reception and idle-listening, in a network where nodes follow a duty cycle scheme. We consider the energy performance of the network for different scenarios, where...
Carrier sensing mechanism has been adopted in IEEE 802.11 MAC for collision avoidance under single channel based wireless ad hoc networks. However, due to the hardware limitation, the carrier sensing mechanism can not help much in single transceiver and multi-channel scenarios. In this paper, we propose a pipelining multi-channel (pi-Mc) MAC protocol for multi-channel ad hoc networks. The core idea...
This paper addresses the problem of resource allocation for a multiclass time-slotted optical overlapped code-division multiple-access (OV-CDMA) network. A fair resource allocation (FRA) scheme is considered with the quality of service (QoS) requirements on both physical layer signal-to-interference ratio (SIR) and MAC layer average packet delay. A cross-layer approach in allocating the transmission...
This paper presents a scheme, called the virtual backoff algorithm (VBA), which is based on the sequencing technique for efficient medium-access control. The proposed method minimizes the number of collisions while reducing the delays that occur during the backoff periods. We present an analytical study on MAC-layer issues, which are very important when accessing a channel over wireless networks....
Power consumption, latency, and complexity are considered to be a benchmark for comparing Medium Access Control (MAC) protocols in Wireless Sensor Networks (WSN). However, the importance of these elements varies according to the application. In this paper, three MAC protocols are proposed for forest fire detection. Basically, two of these protocols are based on the Carrier Sense Multiple Access with...
Fuelled by the phenomenal growth of vehicular and air traffic, motorways and airports are considered to be among the most dynamic environments known. Providing adequate and reliable communication facilities to motorway and airport users is extremely challenging due to the high variability of the environments in which they operate. Moreover, maintaining quality of service (QoS) for all traffic classes...
A lightweight MAC and network layer protocol suite for underwater acoustic communication has been developed. The protocol suite covers the MAC layer, hop-by-hop acknowledgement, multi-hop routing and transmission and includes a network discovery and route generation module. The protocols are currently implemented in a simulator for verification and performance evaluation. By summer 2009 the protocols...
A medium access control (MAC) protocol permits the nodes to access the shared medium by providing contention resolution mechanism. The design of MAC protocol in ad hoc networks becomes a more challenging task due to the interruptible energy source or limited battery life of nodes. This brings energy efficiency as the preliminary goal of the MAC protocol. MAC protocol for underwater acoustic sensor...
In wireless sensor networks (WSN), individual sensor nodes are inherently unreliable and have very limited capabilities to ensure real-time properties. In fact, one of the most predominant limitations in wireless sensor networks is energy consumption, which hinders the capacity of the network to provide real-time guarantees (e.g. low duty-cycles, low transmission range). Many approaches have been...
In this paper we describe a new MAC protocol for ad hoc networks called distributed point coordination function (DPCF). It constitutes an extension of the PCF of the IEEE 802.11 standard to operate over infrastructureless networks. It combines both the operation of DCF and PCF. Users get access to the channel through the DCF function. However, once they get access to the channel, they establish a...
In this paper, we present an analytic model for evaluating the delay, delay jitter and the packet loss probability in multi-hop ad hoc networks using the IEEE 802.11 distributed coordination function (DCF) as MAC protocol. By modeling each node as a discrete time G/G/1 queue, we derive the closed form expressions of the end-to-end delay, delay jitter and the packet loss probability for different circumstances...
Medium access control (MAC) is a key issue for the efficiency of IEEE 802.11 wireless local area network. Legacy 802.11 DCF, using CSMA/CA and a random back-off mechanism, provides a simple-to-implement solution, however it achieves very low throughput. Exploiting the existence of a central entity in the infrastructure mode of an 802.11 wireless network, we propose a new centralized scheduling-based...
In IEEE 802.11, multicast protocol is based on the basic access procedure of Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA). This protocol does not provide any recovery mechanism for multicast frames. As a result, transmitted multicast frames may be lost due to collisions or errors. Recently, several reliable multicast protocols at MAC layer have been proposed for 802.11. They can...
Media access control (MAC) protocols of wireless sensor networks (WSNs) must minimize the radio energy costs in sensor nodes. Latency and throughput are also important design features for MAC protocols in the current WSNs applications. But most of them cannot guarantee quality for real-time traffic. This paper studies the state of the art of current real-time MAC protocols, and then introduces a medium...
Broadcast/multicast is a service of paramount importance for wireless users, which poses several serious challenges. Many multicast applications, such as multicasting streaming or alarm signalling, require a reliable and efficient medium access control (MAC) layer. However, the current IEEE 802.11 protocol does not offer any MAC layer recovery mechanisms on unsuccessfully delivered broadcast/multicast...
Broadcast communications is critically important in vehicular networks. Many safety applications need safety warning messages to be broadcast to all vehicles present in an area. Design of a medium access control (MAC) protocol for vehicular networks is an interesting problem because of challenges posed by broadcast traffic, high mobility, high reliability and low delay requirements of these networks...
This paper proposes AREA-MAC, a medium access control (MAC) protocol for wireless sensor networks (WSNs). AREA-MAC reduces latency and energy consumption of nodes by using low power listening (LPL) with short preamble messages. Other protocols like B-MAC use long preamble messages that cause higher latency, energy consumption, and control overhead on nodes. AREA-MAC provides a reasonable trade-off...
This paper presents the impact of the Automatic Repeat Request (ARQ) parameters value over the IEEE 802.16 Medium Access Control (MAC) layer performance. We analytically analyzed the ARQ blocks delay and discarding probability, as well as the achieved MAC layer throughput, and compared the results with the experimental measurements conducted on a protocol prototype specially developed for this purpose...
OBS ring networks inherently suffer from the resource contention due to the limited network resources and the one-way reservation. Multiple tokens with the help of control information table (CIT) have been applied to avoid the source and wavelength collision. However, the receiver collision cannot be completely avoided as tokens are processed in a distributed manner. In round-robin (RR) queue selection...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.