Reliable Multimedia Broadcasting over Dense Wireless Ad-Hoc Networks (Invited Paper)

Abstract

<p class="MsoNormal" style="margin: 0cm 0cm 0pt; layout-grid-mode: char;"><span style="mso-bidi-font-weight: bold;"><span style="font-size: x-small;"><span style="font-family: Times New Roman;">Broadcasting is an essential operation for Wireless Ad Hoc Networks to perform routing path discovery, and it has become the predominant technology for message dissemination in Vehicular Ad Hoc Networks (VANETs). In the reactive routing schemes of wireless ad hoc network, Routing Request (RREQ) packets are broadcast from the source, and once received the destination traces back the broadcasting path to build an on-demand route. In VANETs, different broadcasting schemes have been proposed for safety, comfort, and commercial applications. However, broadcasting usually generates a lot of redundant messages which would cause excessive channel contention and packet collisions, especially when the density of the network becomes higher. In this survey article, we first introduce the most common data dissemination techniques used in wireless ad hoc networks. After that, we discuss techniques that have been proposed to mitigate the broadcast storm problem. Finally, we introduce an effective model for analyzing the broadcasting schemes, and based on the model we propose an adaptively adjusted probabilistic scheme that highly improves the reliability of broadcasting in dense ad hoc networks.</span></span></span></p&gt

Availability evaluations for IPTV in VANETs with different types of access networks

“…In this case, again assuming three lanes per direction, SP [1] = 100 km/h, SP [2] = 120 km/h and SP [3] = 140 km/h, …”

“…We assume the highway has three lanes per direction and that SP [1] = 80 km/h and SP [2] = SP [3] =100 km/h, respectively, and the minimum distance between the vehicles on the three lanes are d avg [1] = 20 m and d avg [2] = d avg [3] = 30 m (same for each direction). Besides investigating situations with exactly these minimum distances, we are going to study this scenario with 2 × Minimum d avg [i] and also 4 × Minimum d avg [i] .…”

“…In this mobility scenario, we assume SP [1] = 110 km/h, SP [2] = 140 km/h and SP [3] = 160 km/h, respectively and thus the minimum distances between the vehicles are d avg [1] = 35 m, d avg [2] = 45 m and d avg [3] = 55 m. Moreover, different distances of 2 × Minimum d avg [i] and also of 4 × Minimum d avg [i] are also studied in this scenario.…”

“…In VANETs, nodes have high mobility, long battery life and specific, strongly restricted, mobility patterns. As shown in Figure 1, the major goals of the VANET are to enable vehicle-to-vehicle (V2V) or vehicle to infrastructure (V2I)/Road-Side-Unit (RSU) communications so as to provide more safety, comfort and entertainment to the passengers [1].…”

Multimedia data in hybrid vehicular networks

“…An attractive application of VANETs is sharing of multimedia data such as songs and video clips (called reports in this paper) [3,7,8,9,14,15]. Existing studies explored two paradigms of sharing multimedia data in VANETs, namely push (data-to-query) and pull (query-to-data).…”