An All-to-All Multicast Routing Protocol in a Wireless Ad-Hoc Network to Improve Channel Utilization

Wireless Ad-hoc network has become more and more popular. Several different multicasting schemes for this type of network have been developed. But most of them are targeting a situation where the total number of senders is much less than the total number of receivers. This thesis analyzes different wireless communication patterns in ad hoc network, the trend for wireless communication and presents a new multicast scheme. It targets an ad-hoc network where all mobile hosts act as both senders and receivers. The proposed scheme in this thesis will reduce overheads by combining data packets that are destined for the same mobile hosts. The action of combining jobs will be done at mobile hosts which are not joined in the multicasting group and only functioned as forwarders

Xcast Based Routing Protocol For Push To Talk Application In Mobile Ad Hoc Networks

Mobile ad-hoc networks comprise a type of wireless network that can be easily created without the need for network infrastructure or administration. These networks are organized and administered into temporary and dynamic network topologies. Unfortunately, mobile ad-hoc networks suffer from some limitations related to insufficient bandwidth. The proliferation of new IP Multimedia subsystem services (IMs), such as Push-to-talk (PTT) applications consume large amounts of bandwidth, resulting in degraded QoS performance of mobile ad-hoc networks. In this thesis, a Priority XCAST based routing protocol (P-XCAST) is proposed for mobile ad-hoc networks to minimize bandwidth consumption. P-XCAST is based on demand route requests and route reply mechanisms for every destination in the PXCAST layer. To build the network topology and fill up the route table for nodes, the information in the route table is used to classify the XCAST list of destinations according to similarities on their next hop. Furthermore, P-XCAST is merged with a proposed Group Management algorithm to handle node mobility by classifying nodes into two types: group head and member. The proposed protocol was tested using the GloMoSim network simulator under different network scenarios to investigate Quality of Service (QoS) performance network metrics. P-XCAST performance was better by about 20% than those of other tested routing protocols by supporting of group size up to twenty receivers with an acceptable QoS. Therefore, it can be applied under different network scenarios (static or dynamic). In addition Link throughput and average delay was calculated using queuing network model; as this model is suitable for evaluating the IEEE 802.11 MAC that is used for push to talk applications. The analytical results for link throughput and average delay were used to validate the simulated results

Design and investigation of scalable multicast recursive protocols for wired and wireless ad hoc networks

The ever-increasing demand on content distribution and media streaming over the Internet has created the need for efficient methods of delivering information. One of the most promising approaches is based on multicasting. However, multicast solutions have to cope with several constraints as well as being able to perform in different environments such as wired, wireless, and ad hoc environments. Additionally, the scale and size of the Internet introduces another dimension of difficulty. Providing scalable multicast for mobile hosts in wireless environment and in mobile ad hoc networks (MANETs) is a challenging problem. In the past few years, several protocols have been proposed to efficient multicast solutions over the Internet, but these protocols did not give efficient solution for the scalability issue. In this thesis, scalable multicast protocols for wired, wireless and wireless ad hoc networks are proposed and evaluated. These protocols share the idea of building up a multicast tree gradually and recursively as join/leave of the multicast group members using a dynamic branching node-based tree (DBT) concept. The DBT uses a pair of branching node messages (BNMs). These messages traverse between a set of dynamically assigned branching node routers (BNRs) to build the multicast tree. In the proposed protocols only the branching node routers (BNRs) carry the state information about their next BNRs rather than the multicast group members, which gives a fixed size of control packet header size as the multicast group size increases, i.e. a good solution to the problem of scalability. Also the process of join/leave of multicast group members is carried out locally which gives low join/leave latency. The proposed protocols include: Scalable Recursive Multicast protocol (SReM) which is proposed using the DBT concepts mentioned above, Mobile Scalable Recursive Multicast protocol (MoSReM) which is an extension for SReM by taking into consideration the mobility feature in the end hosts and performing an efficient roaming process, and finally, a Scalable Ad hoc Recursive Multicast protocol (SARM) to achieve the mobility feature for all nodes and performing an efficient solution for link recovery because of node movement. By cost analysis and an extensive simulation, the proposed protocols show many positive features like fixed size control messages, being scalable, low end to end delay, high packet rate delivery and low normalized routing overhead. The thesis concludes by discussing the contributions of the proposed protocols on scalable multicast in the Internet society

Supporting Protocols for Structuring and Intelligent Information Dissemination in Vehicular Ad Hoc Networks

The goal of this dissertation is the presentation of supporting protocols for structuring and intelligent data dissemination in vehicular ad hoc networks (VANETs). The protocols are intended to first introduce a structure in VANETs, and thus promote the spatial reuse of network resources. Segmenting a flat VANET in multiple cluster structures allows for more efficient use of the available bandwidth, which can effectively increase the capacity of the network. The cluster structures can also improve the scalability of the underlying communication protocols. The structuring and maintenance of the network introduces additional overhead. The aim is to provide a mechanism for creating stable cluster structures in VANETs, and to minimize this associated overhead. Further a hybrid overlay-based geocast protocol for VANETs is presented. The protocol utilizes a backbone overlay virtual infrastructure on top of the physical network to provide geocast support, which is crucial for intervehicle communications since many applications provide group-oriented and location-oriented services. The final contribution is a structureless information dissemination scheme which creates a layered view of road conditions with a diminishing resolution as the viewing distance increases. Namely, the scheme first provides a high-detail local view of a given vehicle\u27s neighbors and its immediate neighbors, which is further extended when information dissemination is employed. Each vehicle gets aggregated information for road conditions beyond this extended local view. The scheme allows for the preservation of unique reports within aggregated frames, such that safety critical notifications are kept in high detail, all for the benefit of the driver\u27s improved decision making during emergency scenarios

Mengenal pasti masalah pemahaman dan hubungannya dengan latar belakang matematik, gaya pembelajaran, motivasi dan minat pelajar terhadap bab pengawalan kos makanan di Sekolah Menengah Teknik (ert) Rembau: satu kajian kes.

Kajian ini dijalankan untuk mengkaji hubungan korelasi antara latar belakang Matematik, gaya pembelajaran, motivasi dan minat dengan pemahaman pelajar terhadap bab tersebut. Responden adalah seramai 30 orang iaitu terdiri daripada pelajar tingkatan lima kursus Katering, Sekolah Menengah Teknik (ERT) Rembau, Negeri Sembilan. Instrumen kajian adalah soal selidik dan semua data dianalisis menggunakan program SPSS versi 10.0 untuk mendapatkan nilai min dan nilai korelasi bagi memenuhi objektif yang telah ditetapkan. Hasil kajian ini menunjukkan bahawa hubungan korelasi antara gaya pembelajaran pelajar terhadap pemahaman pelajar adalah kuat. Manakala hubungan korelasi antara latar belakang Matematik, motivasi dan minat terhadap pemahaman pelajar adalah sederhana. Nilai tahap min bagi masalah pemahaman pelajar, latar belakang Matematik, gaya pembelajaran, motivasi dan minat terhadap bab Pengawalan Kos Makanan adalah sederhana. Kajian ini mencadangkan penghasilan satu Modul Pembelajaran Kendiri bagi bab Pengawalan Kos Makanan untuk membantu pelajar kursus Katering dalam proses pembelajaran mereka

A load-balanced complete-exchange multicast protocol for wireless Ad-Hoc networks

[[abstract]]Complete-exchange multicasting is quite useful for numerous applications. We explicate a load-balanced complete-exchange multicast protocol (LCM), based on passive clustering, for wireless ad-hoc networks. From a logical viewpoint, LCM constructs multiple cluster structures to balance the traffic loads among all group members. It further avoids overloading of nodes or traffic congestion on the route. In LCM, an innovative scheme is devised to deal with the scenario in which a node plays different roles for different cluster structures. Simulation results show that LCM not only preserves all the advantages of passive clustering, but also performs very efficiently in complete-exchange multicasting. Consequently, LCM is really a feasible solution for load-balanced complete-exchange multicasting, especially for dense networks.[[conferencetype]]國際[[conferencedate]]20040627~20040629[[booktype]]紙本[[conferencelocation]]Chengdu, Chin

A NEW APPROACH OF MULTICAST ROUTING PROTOCOLS IN MANETS BASED ON CBR (CASE-BASED REASONING) METHOD

Multicast routing protocols significantly increase the performance of the network using a new approach of group-orientedservices which become recently apparent for MANETs. Due to this reason several MANET-specific multicasting routingprotocols have been proposed. Although numerous challenges in designing multicast routing protocols in MANETs becomeostensible due to node mobility, contention for channel access, multi hop communications and dynamic topology,researchers tend to address such problems by designing simple, scalable and robust routing protocols. In this paper tried toexplore the existing On-Demand Multicast Routing Protocol (OMRP) with its limitation and propose a new approach ofCBR based multicast routing protocols without changing the basic structure of the protocol. Nodes with CBR based OMRPbecome autonomous by keeping track of previous route discovery experience to reuse back as a solution. This will reducechannel overhead and improves the scalability of the ad hoc network.Keywords: Mobile ad hoc networks (MANETs), Multicast Routing Protocols, and Case-Based Reasoning (CBR)