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The purpose of this paper is to introduce a resource allocation mechanism for Multimedia Broadcast/Multicast Service (MBMS) in a wireless cellular system and to obtain a rapid and efficient transmission scheme over various types' services. The proposed algorithm is evaluated by simulation results.

A big problem for wireless communication is the limited time/frequency resources. Therefore, the most important issue is how to utilize these limited resources to transmit various services over a wireless broadband network, especially for MBMS services. In this paper, resource allocation mechanism in a full unicast system is first analyzed with three classical methods, then improved modulation and coding schemes (MCS) methods are proposed in a full multicast system to improve system throughput and spectral efficiency. Based on the foregoing discussions, research on resource allocation mechanism for mixed multicast and unicast traffic is developed in single‐cell and multi‐cell system (MBSFN, MBMS over single frequency network), respectively. Different transmission proportions between multicast and unicast are analyzed and a multiplexing scenario is also considered.

Resource allocation is a hot topic in wireless communication and there are many investigations on it. However, resource allocation for multicast system, especially for mixed multicast and unicast traffic system, is still a problem worthy of further study. Under same transmission condition in a single cell scenario, system throughput in multicast mode is worse than in unicast mode, which is partly because the number of valid date in multicast resource block (RB) is less than the one in unicast in 3GPP LTE/LTE‐A, on the other hand, because that multicast need to select a relative low MCS to satisfy most MBMS users, even the users with a very poor transmission condition. Fortunately, multicast in MBSFN (MBMS over single frequency network) transfer mode can largely improve system performance.

Improved MCS selection schemes are proposed for full multicast transmission and three transmission scenarios for mixed multicast and unicast traffic are presented to discuss resource allocation mechanism over various types' services. Simulation results show that system performance of multicast system can be greatly enhanced in MBSFN transmission mode, especially with MIMO technology.

Online auctions on the Internet have become popular. However, the communication techniques currently used in the online auction industry are primarily based on unicast technology. Unicast‐based online auctions suffer from unbearable delay of the communication between the auctioneer and bidders. Recently, multicast is changing the Internet environment, and is penetrating to the online auction field. This study describes a model for multicast‐based online auctions. The laboratory experiments demonstrate that the communication performance of multicast‐based online auctions is significantly better than that of traditional unicast‐based auctions.

Presence of innumerable sensors, complex deduction of contexts from sensor data, and reusability of contextual information impose the requirement of middleware for context aware computing. Smart applications, hosted in myriad devices (e.g. PDA, mobile, PCs), acquire different contexts from the middleware and act intelligently based on the available contexts in a context‐aware computing environment. As the system grows larger, scalable delivery of contexts from the middleware to numerous context‐aware applications will be inevitable. However, pure unicast based or pure broadcast‐based dissemination cannot provide high scalability as well as low‐average latency. The purpose of this paper is to present a scalable context delivery mechanism for the middlewares to facilitate the development of larger context‐aware computing systems.

The proposed scheme is based on hybrid data dissemination technique where the most frequently requested data (e.g. HOT contexts) are delivered through multicast and the rest (e.g. COLD contexts) are delivered through unicast to reduce network traffic. The paper dynamically prioritizes and classifies the HOT and COLD context data depending on the number of requests and longest waiting time. Moreover, the division of bandwidth between the delivery of HOT and COLD contexts reduces average latency. Polling traffic is decreased by incorporating leasing mechanism. Extensive simulation is conducted to evaluate the proposed scheme.

The mechanism dynamically prioritizes and classifies the hot and cold context data depending on the request rate and longest waiting time. The solution addresses the push popularity problem that occurs in the passive as the passive clients access data without sending explicit requests. The leasing mechanism is incorporated to reduce the periodical requests (polling) for better performance.

The paper is of value in presenting a scalable context delivery mechanism for the middlewares to facilitate the development of larger context‐aware computing systems and also in presenting implementation details of a prototype that is developed using Jini framework and Java reliable multicast service (JRMS) library.

This paper is a review of a number routing protocols in the internet of vehicles (IoV). IoV emphasizes information interaction among humans, vehicles and a roadside unit (RSU), within which routing is one of the most important steps in IoV network.

In this paper, the authors have summarized different research data on routing protocols in the IoV. Several routing protocols for IoV have been proposed in the literature. Their classification is made according to some criteria such as topology-based, position-based, transmission strategy and network structure. This paper focuses on the transmission strategy criteria. There exist three types of protocols that are based on this strategy: unicast protocol, broadcast protocols and multicast protocols. This later type is classified into two subclasses: geocast and cluster-based protocols. The taxonomy of the transmission strategy is presented in this study. We discuss the advantages and disadvantages of each type with a general comparison between the five types.

The authors can deduce that many challenges are encountered when designing routing protocols for IoV.

A simple and well-explained presentation of the functioning of the IoV is provided with a comparison among each categories of protocols is well presented along with the advantages and disadvantages of each type. The authors examined the main problems encountered during the design of IoV routing protocol, such as the quick change of topology, the frequent disconnection, the big volume of data to be processed and stored in the IoV, and the problem of network fragmentation. This work explores, compares existing routing protocols in IoV and provides a critical analysis. For that, the authors extract the challenges and propose future perspectives for each categories of protocols.

The purpose of this paper is to show how workflow management can be applied in the context of business networking.

The paper looks at workflow management systems (WfMSs) as an enterprise integration tool and, as such, it shows that WfMS require an appropriate integration infrastructure. The paper then describes how a WfMS that supports business networking can be built.

It is found that business networking requires a decentralized, peer‐to‐peer (P2P) integration infrastructure. On the other hand, it is found that it is possible to develop a generic and reusable workflow engine. Both components are then integrated in order to come up with a solution that supports business networking.

Issues concerning information and document management are not addressed. Neither mechanisms of storage and retrieval of exchanged documents, nor the format/structure of those documents are specified.

The paper assumes that enterprises will be willing to build up a P2P network where they will conduct their business‐to‐business (B2B) exchanges. Then, the proposed solution would allow their business processes to be linked without requiring tight coupling between their information systems.

The paper is useful to IT strategists and researchers dealing with WfMS, B2B integration architectures and applications of P2P technology.

This article focuses on Brazil’s migration to digital television. It shows how, in the case of Brazil, unicasting solely reflected the interests of commercial broadcasters. Comparing Brazil to France and the United Kingdom, it explains why the European choice for multicasting is one of the reasons for the success of digital television penetration in these two countries.

By analyzing viewing shares and the financial relevance of the public broadcasters, BBC, and France Televisions, to the national broadcasting spaces, the study concludes that these European traditional broadcasters profited from digital television, despite their exposure to a more competitive environment.

As I will discuss, the model chosen in Brazil continues to hamper Public Service Broadcasting (PSB) and national audiovisual industries’ developments, as well as slowing digital take-up. In Brazil, public broadcasting continued to play a marginal role in the national broadcasting space and the audiovisual market, concentrated in a few local companies.

The findings of this comparative study, developed from a political economy perspective, provide important insights into both Brazilian and European telecommunications policy.

Group communication has become increasing important in mobile ad hoc networks (MANET). Current multicast routing protocols in MANET have been shown to incur large overheads due to dynamic network topology. To this end, this paper proposes an overlay multicast scheme in MANET that is more efficient.

The approach is to construct an overlay multicast tree based on the locations of the group nodes. The paper proposes several tree construction algorithms, namely, location‐guided k‐ary (LGK) tree, location‐guided directional (LGD) tree and location‐guided Steiner (LGS) tree. All of them rely on the geometric locations of the nodes as heuristics to construct the tree. The paper also introduces several mechanisms to enhance the proposed algorithms.

The simulation results show that the location‐guided heuristics is very effective in constructing low bandwidth cost overlay multicast trees in MANET. When location information is up‐to‐date, the bandwidth cost of a LGS tree is similar to that of an optimal router‐assisted Steiner multicast tree. When location information is out‐dated, LGD tree has the lowest cost.

This paper demonstrates the effectiveness of location‐guided heuristics in constructing overlay multicast trees in MANET. This study strongly suggests that location‐guided heuristics can be used to design many other algorithms in a mobile network.

This paper aims to describe the design, implementation, and evaluation of a novel file and application sharing system that enables a group of mobile stations that do not have any prior security association and infrastructure support, to form a secure collaboration workspace, and share files and application content instantly with minimal human intervention.

The paper looks at the system implementation and experimentation.

WShare can automatically establish a peer‐to‐peer network among the participating mobile stations, and provides a transparent shared file repository through which the mobile stations can securely exchange files with simple drag‐and‐drop operations. This file sharing application can also be specialized to support the same file beaming service over wireless LAN as that provided by Palm PDAs over infrared links. On the application sharing front, WShare supports a general remote execution mechanism that can synchronize the state of multiple instances of a standard productivity application, such as PowerPoint, Excel, and Word, across different machines. Finally for sharing generic applications, WShare also integrates virtual network computing with reliable wireless broadcast to provide a user‐interface level sharing mechanism. Performance measurement on the fully operational WShare prototype shows that a collaboration workspace among five mobile nodes can be set up within 3.5 seconds.

This paper proposes a new communication paradigm and presents the design, implementation, and evaluation of a fully‐working prototype.

This paper aims to discuss problems, requirements and current trends for deploying group communication in real‐world scenarios from an integrated perspective.

The Hybrid Shared Tree is introduced – a new architecture and routing approach to combine network – and subnetwork‐layer multicast services in end‐system domains with transparent, structured overlays on the inter‐domain level.

The paper finds that The Hybrid Shared Tree solution is highly scalable and robust and offers provider‐oriented features to stimulate deployment.

A straightforward perspective is indicated in the paper for a mobility‐agnostic routing layer for future use.

Distributed, real‐time multiplayer computer games (MCGs) are in the vanguard of utilizing the networking possibilities. Although related research has been done in military simulations, virtual reality systems, and computer supported cooperative working, the suggested solutions diverge from the problems posed by MCGs. With this in mind, this paper provides a concise overview of four aspects affecting networking in MCGs. First, networking resources (bandwidth, latency, and computational power) set the technical boundaries within which the MCG must operate. Second, distribution concepts encompass communication architectures (peer‐to‐peer, client/server, server‐network), and both data and control architectures (centralized, distributed, replicated). Third, scalability allows the MCG to adapt to the resource changes by parametrization. Finally, security aims at fighting back against cheating and vandalism, which are common in online gaming.