Multihop data delivery through vehicular ad hoc networks is complicated by the fact that are highly mobile and frequently disconnected. To address this issue, we adopt idea of carry forward, where a moving vehicle carries packet until new moves into its vicinity forwards packet. Being different from existing forward solutions, make use predictable mobility, which limited traffic pattern road layout. Based on pattern, can find next to reduce delay. We propose several vehicle-assisted (VADD)...

Vehicular ad hoc networks (VANETs) have recently received considerable attention. To support VANET-based applications, it is important to disseminate data from an information source (data center) many vehicles on the road. Although disseminating a server large number of clients has been studied in database community and network community, unique characteristics VANET bring out new research challenges. In this paper, we propose pouring (DP) buffering paradigm address dissemination problem...

As vehicular networks become popular, more and people want to access data from their vehicles. When many vehicles through a roadside unit, scheduling becomes an important issue. In this paper, we identify some challenges in vehicle-roadside access. move pretty fast, the requests should be served quickly. Also, may upload hence download compete for same bandwidth. To address these challenges, propose several schemes. We first basic scheme called D*S consider both service deadline size. then...

Recently, some researchers have performed extensive experiments to study the feasibility and performance of vehicle drive-thru access roadside points (APs). The demonstrate that duration connectivity AP is limited. A has an area high signal strength near AP, but experiences poor link quality when entering or exiting coverage area. Since a spends large portion connection time in this area, data throughput can be significantly reduced. This problem been identified several works, viable...

In vehicular Ad-hoc networks (VANETs), vehicles can gain short connections to the Internet by using wireless access points (AP). A significant part of connection time is required for acquiring an IP address via dynamic host configuration protocol (DHCP). Depending on a vehicle's speed and AP coverage area, DHCP consume up 100 percent available time. We propose Passing Protocol reduce overhead obtaining under one-tenth second. This done without modifying either or software. explore scalable...

Congestion has always been a serious problem for all kinds of communication networks. Wireless sensor networks (WSN) face special difficulties in dealing with congestion due to their unique requirements and constraints. Various control schemes WSN have proposed recently. These try solve the either at MAC layer or through cross-layer approach. This paper explores these tries find common features, which may direct future research.

Whether the current IEEE 802.11p communication system meets stringent quality of service (QoS) requirements for safety applications or not is still very clear. Signal-to-interference-plus-noise ratio (SINR) distribution plays a primary role in quantifying QoS as well link capacity one-dimensional (1-D) highway and two-dimensional (2-D) intersection road. Most analytical models based on stochastic geometry assumed ALOHA access to analyze SINR distribution, while few works developed model...

To enhance traffic safety on mountainous roads, this study proposes an innovative CNN-LSTM-Attention model designed for the identification of near-crash events, utilizing naturalistic driving data from challenging terrains in Yunnan, China. A combination a threshold method complemented by manual verification is used to label and annotate events within dataset. The importance vehicle motion features evaluated using random forest algorithm, revealing that specific variables, including x-axis...

A new effective interference-based capacity model was proposed for vehicular ad hoc network safety message broadcast scenario in M. Ni <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">et al.</i> ( xmlns:xlink="http://www.w3.org/1999/xlink">Commun. Lett.</i> , vol. 19, no. 4, pp. 621–624, Apr. 2015). This letter is a reconsideration and extension of the . First, we point out that analysis incomplete show derivation node transmission probability...

NS-2, as an open-source network simulator, is widely used in wireless communication studies and VANET safety applications. In [1], Chen et al. implemented a completely modified architecture about IEEE 802.11 MAC physical layer modules which depicted the signal transmission reception process 802.11, well method of handling collision. However, using latest version NS2, we found some problems. First, its approach deciding whether to receive by comparing SINR threshold not flexible actual...

This letter proposes a new approach to the reliability analysis of IEEE 802.11 one-dimensional (1-D) broadcast mobile ad hoc networks. The finds simple and effective way derive distribution signal-to-interference-to-noise ratio (SINR) on each receiver, which is required for evaluation metrics channel capacity. Having observed that interference area depends given SINR threshold, derivation converted estimating threshold related areas are dynamically changed in communication channel. applied...

In a vehicular ad hoc network (VANET) based on IEEE 802.11p, the performance of communication link is heavily influenced by interference. To quantify impact interference, analytical models usually explicitly or implicitly assumed interference range beyond which ignored. We find that potential maximum should be related to minimum power device can perceive. However, most previous works VANET modeling simply fixed range. The recently proposed effective dependent signal-to-interference-and-noise...

Mobile service will be more various and handover have to adapt different quality-of-service (QoS) requirements of all kinds in 4G mobile communication systems. In the paper, a dynamic priority queue scheme is proposed. With scheme, common manager (CQM) appended can changed according variety waiting delay. Furthermore, resource graded reserved, which insure access high service. The proposed adapted QoS requirements, significantly improve system performance, reduce drop rate block rate.

For reducing the computation overhead spent on processing received raw data in wireless sensor networks, a target positioning algorithm featuring filtering is proposed. In this algorithm, parameter, which defined as ratio of triangular area determined by certain three selected nodes to maximum some moving around same concentric circles centered at target, introduced. Since it proved that node groups with larger ratios have less upper bound errors, new utilize parameter filter massive ranging...