Search results for "Wireless Application Protocol"
showing 9 items of 9 documents
Refinements on IEEE 802.11 Distributed Coordination Function Modeling Approaches
2010
With the popularity of the IEEE 802.11 standards, many analytical saturation throughput studies for the distributed coordination function (DCF) have been reported. In this paper, we outline a number of issues and criticalities raised by previously proposed models. In particular, a careful look at backoff counter decrement rules allows us to conclude that, under saturation conditions, the slot immediately following a successful transmission can be accessed only by the station (STA) that has successfully transmitted in the previous channel access. Moreover, due to the specific acknowledgment (ACK) timeout setting adopted in the standard, the slot immediately following a collision cannot be ac…
Mobile Wireless Interfaces: In Search for the Limits
2002
With the proliferation of 2G and 3G Telecom and other wireless networks hundred of millions of users will be able to access wireless services with their terminals in only a few years. In this paper we discuss the possibilities and limitations of existing and emerging mobile technologies and methodologies for porting information and functionality from traditional PCs to mobile devices and vice versa. We argue that in order to be able to properly port things between devices an equivalence concept for user interfaces is required.
Cyber Security for Wireless Semantic (SCADA/DCS) Systems
2016
International audience; Supervisory Control and Data Acquisition and Distributed Control Systems named (SCADA/DCS) have played a key role in the design of modern power smart applications, particularly in the automatic management of real time energetic platforms. In this work, we present a semantic cyber security vulnerabilities add to classic one, with the use of semantic embedded application in smart devices in semantic wireless (SCADA/DCS) systems, focusing on the semantic attacks. In this work, we present a new security semantic wireless protocol as a secure communication support for these modern semantic wireless systems named (ZIGBEE/SOAP/SECURITY), obtained by the combination between …
A Group-Based Protocol for Large Wireless AD-HOC and Sensor Networks
2008
Many routing protocols for ad-hoc networks and sensor networks have been designed, but none of them is based on groups. It is known that grouping nodes gives better performance to the group and to the whole system, thereby avoiding unnecessary message forwarding and additional overheads. We propose an approach where the network is split into several groups of sensors where connections between groups are established as a function of the proximity and the neighbor's available capacity (based on the sensor's energy). In this paper the network architecture is described with its mathematical description and the messages that are needed to proper operation. It is also simulated how much time is n…
M-commerce - mobile commerce: a new frontier for E-business
2005
Mobile commerce involves the use of mobile computing devices in carrying out different types of economic transactions or enabling them to take place over space and time. The m-commerce includes use of such technologies as SMS services over a number of carriers (GSM, IS95, CDMA, W-CDMA), Bluetooth applications, and the integration of low-level digital carriers to IP based services through WAP or Compact HTML like the Japanese I-Mode service. This integration is one of the fastest growing markets of E-business and it will involve the development and design of a host of new applications, services, business models and technological solutions. The theme is both topical and challenging, as the nu…
Preamble Sampling MAC Protocol for Low Power Wireless Sensor Networks with IEEE 802.15.4 Transceivers
2006
In this paper a preamble sampling MAC protocol for low power wireless sensor networks is proposed. The article describes the implementation of the protocol using network nodes equipped with the Chipcon CC2420 802.15.4 transceiver. The power consumption of the transceiver has been measured and the MAC protocol has been adapted to the transceiver properties. The results show the trade-off between power consumption and transmission delay for this algorithm during the communication process.
A Wireless Mesh Network-based System for Hotspots Deployment and Management
2007
In recent years Wireless Local Area Networks (WLANs) or hotspots, as they are commonly known, have emerged as a promising networking platform to extend network connectivity in public venues, providing local coverage for Internet applications on the move in urban areas and rural environments. Wireless hotspots using 802.11-based technology have popped up in corporate offices, coffeehouses, airports, restaurants and bookstores worldwide. For all their utility and ease of use the 802.11 wireless protocol, known as WiFi, has become the mobile connectivity mechanism of choice for business people, travelers, villagers, and everyone else. Unfortunately, even with the protocol's ease of use and its…
Mobile Electronic Commerce: Emerging Issues
2000
There are many definitions for Mobile Electronic Commerce (M-Commerce). We define M-Commerce as any type of transaction of an economic value having at least at one end a mobile terminal and thus using the mobile telecommunications network. The Wireless Application Protocol (WAP) plays an important role in m-commerce by optimizing Internet standards for the constraints of the wireless environment and thus bridging the gap between Internet and mobile world. Mobile Network Operators can play a major role in m-commerce by being strategically positioned between customers and content/service providers. In this paper we investigate the roles the operator can play in m-commerce and discuss respecti…
A Multi-Relay Cooperative Automatic Repeat Request Protocol in Wireless Networks
2010
This paper proposes a Multi-relay Cooperative Automatic Repeat ReQuest protocol (MC-ARQ) for IEEE 802.11 based wireless networks. The proposed distributed relay selection scheme not only selects the best relays but also solves the collision problem among multiple contending relays, by sorting the relays in the network according to their instantaneous channel quality with the destination node. No prior information or explicit signaling among relay nodes is required. Both analytical and simulation results show that significant benefits can be achieved with the MC-ARQ protocol, compared with both the recently proposed PRCSMA scheme and the original non-cooperative DCF scheme.