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Buffer management techniques are essential while handling multicast streaming in MANET since real-time data will involve playback delay and jitter. In this paper, an efficient buffer management protocol is developed for streaming data in multicast groups. The frequently requested video data can be buffered in any intermediate nodes along the multicast tree from the source to the receivers. When packets are received, they are classified as real-time or non-real-time and placed into respective queues. Cumulative weight of the packets in the real-time buffer is then estimated based on number of hops, deadline and waiting time. Based on the estimated weight value, transmission priorities are assigned. The buffer space is dynamically adjusted depending on the number of intermediate nodes along the multicast tree from the source to the receivers. Simulation results show that the proposed buffer management protocol reduces the latency and energy consumption while increasing the packet delivery ratio.

Multicast is widely applied in cloud data centers. Because intermediate nodes can encode the packets, network coding improves the capacity and robustness of multicast applications. However, this system is vulnerable to pollution attacks. Existing schemes mainly focus on homomorphic cryptographic technologies against such attacks. However, the homomorphic cryptographic technology introduces complicated key management and calculation and storage overhead. This paper proposes a novel, fast, and secure network-coding multicast on software-defined networks. This scheme separates the complicated secure multicast management from fast data transmission. In the control layer, when users and switches try to join the secure multicast, they are authenticated and authorized by the controller. Only trusted nodes can join the forwarding paths. In the data layer, the trusted nodes only forward the data. The proposed scheme can use traditional cryptography without homomorphy; thus, it greatly reduces computation complexity, improves transmission efficiency, and thwarts pollution and eavesdropping attacks.

Current cellular networks support video streaming over unicast or multicast. However, there exists a tradeoff between utilizing the two: i) unicast leads to higher network load, but lower energy consumption of mobile devices, and ii) multicast results in lower network load, but higher energy consumption. To make the best out of both, we propose to concurrently utilize unicast and multicast for minimizing the energy consumption of mobile devices and minimizing the load on cellular networks. Cellular networks support two multicast schemes: i) independent cell networks and ii) multi-cell single frequency networks, where multiple adjacent base stations operate on the same frequency. We first consider the less-complicated independent cell networks, and then extend our solution to single frequency networks for better performance. We formulate the resource allocation in hybrid multicast -unicast streaming systems as a binary integer programming problem. We describe optimal algorithms for the two multicast schemes. We then propose two efficient, heuristic, algorithms that run faster and provide close to optimal results. While our solution is general, for concreteness, we conduct detailed LTE packet-level simulations using OPNET. Our simulation results show the proposed algorithms i) scale to many more mobile devices than the state-of-the-art unicast-only approaches and ii) result in lower energy consumption than the latest multicast-only approaches. In addition, the algorithms designed for multi-cell single frequency networks outperform the algorithms designed for independent cell networks in all aspects, such as service ratio, spectral efficiency, energy saving, video quality, frame loss rate, initial buffering time, and number of re-buffering events.

The mobile network operators are being challenged by the explosion of mobile data traffic in terms of network performance and generated revenue. On one hand, efficient mobility management plays a crucial role to support mobile users, however, the current mobility protocols have several major limitations from their centralized and hierarchical nature (e.g., sub-optimal routing, scalability and reliability issues). Distributed mobility management (DMM) is a new, very promising trend to overcome these limitations by flattening the network architecture and dynamically providing the mobility support. Based on the fact that the mobile Internet traffic will be dominated by the mobile video, the scalability and bandwidth efficiency from multicast routing makes the IP multicast play a crucial role. However, one of the main challenges for multicast support is the mobility of a multicast node, leading to several issues for both multicast service and network operator such as long service disruption, high end-to-end delay, non-optimal routing and traffic replication. Driven from the fact that different multicast flows have very different characteristics and each network operator has different policies for multicast support, we propose a dynamic multicast support scheme (DMMS), taking into account both the user and network operator point of view. DMMS allows to dynamically provide the appropriate multicast support mode based on a set of contexts such as the service’s characteristics, mobility of the node and network context to adapt to the service’s requirements as well as operator’s policies.

MRAGA (Multicast Routing Algorithm based on Genetic algorithm) for the DelayConstrained Minimum-Energy Multicast Routing problem was presented. The genetic operators of this algorithm reduce the transmission delay and energy consumption of multicast trees, thus accelerating the convergence speed of the algorithm. Experiment results show that the multicast tree found by this algorithm not only guarantee the delay constraint, but also has the minimum energy consumption. Furthermore, this algorithm converges quickly.

Many distributed services need to be scalable: internet search, electronic commerce, e-government... In order to achieve scalability, high availability and fault tolerance, such applications rely on replicated components. Because of the dynamics of growth and volatility of customer markets, applications need to be hosted by adaptive, highly scalable systems. In particular, the scalability of the reliable multicast mechanisms used for supporting the consistency of replicas is of crucial importance. Reliable multicast might propagate updates in a pre-determined order (e.g., FIFO, total or causal). Since total order needs more communication rounds than causal order, the latter appears to be the preferable candidate for achieving multicast scalability, although the consistency guarantees based on causal order are weaker than those of total order. This paper provides a historical survey of different scalability approaches for reliable causal multicast protocols., This work was supported by European Regional Development Fund (FEDER) and Ministerio de Economia y Competitividad (MINECO) under research Grant TIN2012-37719-C03-01.

In computer networks, multicast routing is that in which a single message is transmitted to multiple recipients from a subset of devices, called multicast group. To address the multicast routing problem, it is usual to model the computer network as a graph. In line with this, some strategies aim at building a routing tree that minimizes the total costs of transmission between the vertices of the routing tree that contains the multicast group, the Steiner tree. However, in large scale applications, local-based strategies may be a better alternative, since they can also be easily adapted to tackle distributed systems. In the literature, to the extent of our knowledge, to construct approximate Steiner tree using this type of approach remains a challenge. In this paper, we present a neighborhood-based metaheuristic to find an approximate solution for the Steiner tree in graphs. In the computational experiments, we used benchmark instances of small, medium and large scales and compared the results achieved by the proposed strategy with the best found so far. In addition, we analyze a real word instance for which the proposed algorithm has obtained good performance.

In this article, we present RE $^2$ MR, the first hybrid multicast routing protocol that builds on the strengths of existing topology-based, hierarchical and geographic multicast solutions, while addressing their limitations. In RE $^2$ MR, the multicast path search problem is formulated as the capacitated concentrator location problem (CCLP) which yields the network topology that minimizes the sum of path lengths from the multicast root to multicast members. Furthermore, its trajectory-based lightweight hole detection (THLD) discovers deployment area irregularities (i.e., network holes) that affect its solution and autonomously take them into account to generate updated routing paths, and its Energy-efficient Packet Forwarding (EPF) and Multi-level Facility Computation (MFC) reduce computational and communication overheads. We implement RE $^2$ MR in TinyOS and evaluate it extensively using TOSSIM for relatively large-scale simulations (400 nodes); we also implement RE $^2$ MR on real-hardware and perform experiments on a testbed consisting of 42 TelosB motes. Through the simulations and experiments on real-hardware, we demonstrate that RE $^2$ MR reduces the energy consumption by up to 57 percent and the end-to-end delay by up to 8 percent, when compared with the state-of-the-art multicast routing protocols.

Large-scale information dissemination in multicast communications has been increasingly attracting attention, be it through uptake in new services or through recent research efforts. In these, the core issues are supporting increased forwarding speed, avoiding state in the forwarding elements, and scaling in terms of the multicast tree size. This paper addresses all these challenges---which are crucial for any scalable multicast scheme to be successful---by revisiting the idea of in-packet Bloom filters and source routing. As opposed to the traditional in-packet Bloom filter concept, we build our Bloom filter by enclosing limited information about the structure of the tree. Analytical investigation is conducted and approximation formulas are provided for optimal-length Bloom filters, in which we got rid of typical Bloom filter illnesses such as false-positive forwarding. These filters can be used in several multicast implementations, which are demonstrated through a prototype. Thorough simulations are conducted to demonstrate the scalability of the proposed Bloom filters compared to its counterparts.

Many multicast services such as live multimedia distribution and real-time event monitoring require multicast mechanisms that involve network functions (e.g., firewall and video transcoding). Network function virtualization (NFV) is a concept that proposes using virtualization to implement network functions on infrastructure building block (such as high volume servers and virtual machines), where software provides the functionality of existing purpose-built network equipment. We present an approach for building the multicast mechanism whereby multicast flows are processed by NFV before reaching their end users. We propose a routing algorithm and a method for building an appropriate multicast topology.

In a communication network with a source node, a multicast tree is defined as a tree rooted at the source node and all its leaves being recipients of the multicast originating at the source. The tree or bandwidth cost is normally measured by its utilization of tree links along with the quality of service (QoS) measures such as delay constraint and end-to-end delay. However, if nodes are allowed to join or leave the multicast group at any time during the lifetime of the multicast connection, then the problem is known as dynamic multicast routing problem. In this article, we combine a greedy approach with static multicast routing using Tabu Search to find a low-cost dynamic multicast tree with desirable QoS parameters. The proposed algorithm is then compared with several static multicast routing algorithms. The simulation results show that, on a large number of events, i.e., where nodes are leaving or joining, the proposed algorithm is able to find multicast trees of lower cost and more desirable QoS properties.

Due to the ubiquitous use of the Internet and huge proliferation of network devices, the energy consumed by today's networks has increased significantly, implying the need for designing and operating green networks. In this paper, we propose a power-efficient Quality of Service (QoS) routing scheme for multiple many-to-many multicast requests with given static traffic demands in green multi-granularity transport networks, which comprehensively considers both the IP and the optical layers. A chosen probability model is devised to describe the probability of a link being selected when routing, and a heuristic routing algorithm is proposed to construct multiple many-to-many multicast trees in order to decrease power consumption, enhance QoS evaluation and improve resource utilization evaluation under QoS and capacity constraints. Results from simulation experiments demonstrate that our proposed scheme is more power-efficient with higher QoS evaluation and better resource utilization compared with others.

Since internet access is used by billions of people worldwide and the number of internet user is also increasing every day, a new technology called as wireless mesh network (WMN) is becoming popular. This is because it has some desirable characteristic, but it has some limitation for multi-hop routing, bandwidth, and many more. In order to overcome these issues, we proposed Way-Point Multicast Routing Framework (WPMRF) for improving the quality of service (QoS) in Hybrid WMN. Initially, the multicast framework is established based on the minimum load factor. The route established with least load factor is considered, as it avoids any kind of congestion in the network. After that, segmentation of route is done, and the way-point nodes are selected to join the multicast session. After that, the transmission is performed using MAODV and ODMRP protocol. In addition, an estimated route disconnection parameter is used for fast route recovery process and helps to select more reliable route path. The advantage of the proposed work is that it provides more reliable routing path to increase the quality of service (QoS) with fast route recovery process.

Multicast delivery in wireless multi-hop networks has become the popular research topic and holds the important applications such as sensor and tactical networks. However, how to minimize multicast energy consumption and prolong the lifetime of multicast connection in wireless multi-hop networks with limited energy is a challenge at present. This paper presents a new approach to solve this problem by considering the cognitive ability of nodes. Above all, we exploit the directional reception antennas to propose a directional reception two-step reconstruction routing scheme to set up multicast tree for wireless multi-hop networks. Different from previous methods, we grant the cognitive ability to each node so that they can obtain the minimum transmission power by sensing, learning, acting, and deciding. We propose two algorithms to find the minimum transmission power of all the nodes in the multicast tree built above. And a global optimal multicast delivery algorithm with the minimum energy consumption is proposed to implement effective multicast communication for wireless multi-hop networks with energy limited. Numerical experiments show that the proposed approach can significantly improve the multicast performance of wireless multi-hop networks with energy limited such as the lifetime of multicast connection and transmission power.

This work investigates the problem of designing, engineering, and evaluating metropolitan area transparent optical networks for the provisioning of multicast sessions. Apart from finding the minimum-cost tree and using metrics on the physical performance of the system, namely the Q-factor, this work investigates different node architecture designs including architectures with active and passive splitters and architectures with different receiver and transmitter designs. Different network engineering approaches are also utilized and are used to ascertain whether a multicast connection should be admitted to the network. "Tree balancing techniques" are used for routing the multicast sessions, aiming at maximizing the multicast connections that can be admitted to the network.

IP multicast is one of the best techniques for video streaming on the Internet. It faces issues with respect to address allocation, routing, authorization, group management, security, and scalability. By default, local Internet Service Providers did not enable IP multicast services, because of the cost incurred in using multicast-enabled routers. To solve these issues some of the IP layer functionalities have been shifted to the Application Layer, thus leading to Application Layer Multicast (ALM) protocols. However, ALM protocols face issues related to synchronous data delivery, scalability, link stress, link stretch and node failures. Some of the existing protocols are CoolStreaming, and mTreebone. A novel ALM protocol based Push/Pull Smooth video Streaming Multicast (PPSSM) protocol is proposed in this paper, to increase the throughput and reduce the packet loss rate. The PPSSM protocol involves three stages, such as tree-mesh construction, dynamic buffer management and network coding techniques. In the tree-mesh construction, a tree consists of stable nodes and a mesh consists of unstable nodes. The proposed PPSSM optimizes the stable nodes in the tree, which minimizes or eliminates the pull operations from the unstable mesh overlay nodes, by exploring the potential of the stable nodes. Dynamic buffer management is achieved by setting the optimal buffer threshold value, using the optimization of the sensitivity parameters, such as packet loss and packet workload/delay by the Infinitesimal Perturbation Analysis and Stochastic Approximation algorithms. In addition to the tree-mesh construction and buffer management, the introduction of the network coding technique will enhance the throughput and minimize the packet loss and delay. Finally, the performance of the proposed PPSSM protocol is compared with those of CoolStreaming, and mTreebone, and it shows improvement in respect of throughput, packet loss, and average decoding time.

Multicast communication of mobile ad hoc networks (MANET), rather than multiple unicast communication, delivers common content to more than one receiver at a time. Due to cutting-edge communication technology and advancements in terms of radio-mounted devices, groups in front-end war field, as well as rescue troops, are well connected to carry out their missions using multicast communication. The key to the success of military networks in a hostile environment is security and collaboration. Internal attacks are major threats to impose a great failure in their mission goal. We introduce a novel indirect internal stealthy attack and known direct internal stealthy attacks such as black hole and deny-to-forward attacks on tree-based multicast routing protocol. These internal attacks can induce the performance degradation in the multicast group. We design a distributed cross-layer based machine learning anomaly detection system for multicast communication of MANET. Using efficient multilayer features, rather than routing layer features alone, improve the accuracy of the Intrusion Detection System (IDS) in terms of detection of direct and indirect internal stealthy attacks. We evaluate the sensitivity, specificity and detection accuracy of well-known multiclass classifiers in combination with various feature subset selection algorithms. Since our problem with classification is a multiclass, the performance metrics calculated here are different from the binary classifiers. Our IDS is efficient, with respect to high true positives, very low false positives and less resource consumption even in the very challenging conditions of multicast communication of ad hoc networks.

The study of multicast delay performance in mobile ad hoc networks (MANETs) is critical for supporting future multicast-intensive applications in such networks. Different from available works that mainly focus on the study of asymptotic scaling laws of the multicast delay in MANETs, this paper explores the exact multicast delay achievable in MANETs under a general multicast two-hop relay (M2HR)- ( f , g ) algorithm with packet replication limit f and multicast fanout g. In such an algorithm, each packet can be replicated up to f distinct relay nodes and it should be delivered to its g destination nodes through either its source node or these relay nodes. We first develop a Markov chain-based theoretical framework to model the complicated packet delivery process under the M2HR- ( f , g ) algorithm and then determine some basic probabilities related to packet delivery process. With the help of the theoretical framework and related basic packet delivery probabilities, the analytical models are further derived for both the mean value and variance of exact multicast delay. Finally, simulation and numerical results are provided to illustrate the accuracy of the multicast delay models as well as our theoretical findings.

Bloom filter (BF) based forwarding was proposed recently in several protocol alternatives to IP multicast. Some of these protocols avoid the state in intermediate routers and leave the burden of scalability management to the multicast source and end-hosts. Still, the existing BF-based protocols have scalability limitations and require explicit network management as well as non-trivial functionality from the network components. In this work we address the scalability limitations of the BF-based forwarding protocols by partitioning end-hosts into clusters. We propose several algorithms to do the partitioning so as to decrease the overall traffic in the network. We evaluate our algorithms in a real Internet topology, demonstrating the ability of the proposed design to save up to 70% of traffic volume in the large-scale topology for big groups of subscribers, and up to 30% for small groups.

Multicast routing has brought a revolution by enabling the delivery of the same content to a group of receivers simultaneously. However, multicast routing in multichannel multiradio wireless mesh networks has been proved to be an NP-hard problem. To achieve optimal performance in multichannel multiradio wireless mesh networks the channel assignment strategy plays an important role. In this paper, we present an intelligent Quality of service multicast routing and Channel Assignment (i-QCA) algorithm which solves the multicast tree construction and channel assignment problem conjointly by intelligent computational methods. The multicast tree construction algorithm is based on the differential evolution approach. The channel assignments in prior works are mostly oriented toward heuristic or meta heuristic approaches and hence produce suboptimal results. The proposed algorithm consists of a genetic algorithm based channel assignment strategy and determines a delay, jitter bounded minimal interference lowcost multicast tree. Our experimental results clearly show that the proposed algorithm achieves much better performance as compared to Multi Channel Multicast (MCM) and QoS Multicast Routing and Channel Assignment (QoS-MRCA) algorithm in multichannel multiradio wireless mesh network environments.

Currently, multicast in cloud networks without the support of underlay IP multicast relies on one-to-all replications, which wastes networking resources and may induce bottlenecks. In this paper, we point out this issue should be solved as an overlay routing problem and the special architecture of cloud networks should be fully exploited. Then we propose a solution which includes a SDN framework and an algorithm to construct a degree-constrained overlay multicast routing tree. Our simulations show that its performance is better than current solution. Moreover, it can deal with various multicast groups and it scales well with both group size and cloud size.

This paper deals with the problem of optimal association of stations (STAs) to access points (APs) for mulicast services in IEEE 802.11 WLAN. In a multicast session, all the subscribed STAs receive the multicast data packet at the same data rate (R min ) from their respective serving APs. A higher value of R min improves the multicast throughput by completing the ongoing multicast session in lesser time. This also improves the unicast throughput as the cycle duration is shared by the unicast and multicast sessions. To provide multicast services to the STAs, we need to select a minimum cardinality subset of APs as the system message overhead depends on this cardinality. However, such a minimum cardinality subset of APs may not be possible to activate simultaneously due to the limited number of available orthogonal frequency channels. In this paper, we develop a combined greedy algorithm that selects a subset of APs with minimum cardinality for which a conflict-free frequency assignment exists and finds an association between the STAs and the selected APs that maximizes the R min value. Through simulation we have shown that the proposed algorithm selects significantly less number of APs for different R min values in comparison to the well-known metrics for multicast association like RSSI, minimum hop-distance, normalized-cost and in-range STA number.

Addressing key management in mobile multicast communication is currently a booming topic due to the convergence of wireless and mobile technologies. With the proliferation of multiple group based services that are possible to co-exist within a single network, mobile subscribers could subscribe to these services concurrently while ubiquitous. However, the existing group key management (GKM) protocols intend to secure group communication for just a single group service. The GKM approaches involve inefficient use of keys and huge rekeying overheads, hence unsuitable for multiple multicast group environments. In this paper, we propose a novel GKM protocol for multiple multicast groups, called slot based multiple group key management (SMGKM) scheme. SMGKM supports the movement of single and multiple members across a homogeneous or heterogeneous wireless network while participating in multiple group services with minimized rekeying transmission overheads. Unlike conventional GKM protocols, SMGKM protocol can mitigate one-affect-n phenomenon, single point of failure and investment pressure of signaling load caused by rekeying at the core network. Numerical analysis and simulation results of the proposed protocol show significant resource economy in terms of communication bandwidth overhead, storage overheads at the Domain Key Distributor (DKD), mobile receiver and Area Key Distributors while providing intense security.

Multicast routing protocols improve the network performance by optimising the parameters such as bandwidth, channel utilisation and throughput rate. In wireless sensor network, the primary multicast routing protocol is geographic multicast routing. This study proposes core network supported multicast routing (CNSMR) protocol, a stateful-based distributed multicast routing protocol for sensor networks. The proposed protocol comprises of heterogeneous nodes such as cluster head (CH) nodes, core nodes (CNs) and sensor nodes (SNs). The distinct set of nodes known as CNs have computing, storage and energy resources more than the SNs. CH nodes and CNs form the core network, and CNs with core network and SNs form the core network supported multicast tree. SNs participate in multicast routing supported by the core network and thus save the node energy. Multicast routing in the proposed core network supported multicast trees balance the load in the network and improve the network performance as compared to the existing WSN multicast routing protocols. The proposed CNSMR protocol is compared with the existing WSN multicast routing protocols such as DCME-MR, Intelligent-MR, H-GMR and OnDemand-MR. Simulation results indicate improvements in delay latency, energy save ratio, throughput rate, end-to-end packet delay, multicast control overhead ratio and packet delivery ratio for the proposed protocol.

The objective of this paper is to design radio resource management policies for supporting the effective delivery of multicast service in Long-Term Evolution Advanced (LTE-A) systems. Specifically, we propose multicast subgrouping-based solutions to maximize the system efficiency in terms of throughput under the constraints that 1) all user equipment devices are served and that 2) fairness among the activated multicast subgroups is guaranteed to avoid users' dissatisfaction. These results are obtained by modeling the multicast subgroup formation problem through a bargaining game. Moreover, an algorithm, which achieves the optimal fairness–efficiency tradeoff, is proposed to support the system in selecting the most appropriate solution in terms of 1) subgroups activated over each system carrier and 2) resource allocated to them.

This paper proposes a novel video delivery scheme that reduces the bandwidth consumption cost from a video server to terminals in Long-Term Evolution networks. This proposed scheme combines optimized hybrid multicast with a segment-based caching strategy for use in environments where the maximum number of multicast channels is limited. The optimized hybrid multicast, allocation of multicast channels, and cache allocation are determined on the basis of a video's request rate, the related video's length, and the variable cost per unit size of a segment belonging to the related video. Performance evaluation results show that the proposed scheme reduces a video's delivery costs. This work is applicable to on-demand TV services that feature asynchronous video content requests.

Mobile devices can exist in many forms. IEEE 802.11 and IEEE 802.16 create a heterogeneous network. Heterogeneity implies that some devices are more powerful than others, and some can be servers while others can only be clients. Typical IEEE 802.11 b/g/a is considered up to 54 Mbit/s.WiMax IEEE [802.16] has the specification of Medium Access Control (MAC) also Physical (PHY) layers. The results analyze the validity of broadcast and multicast in heterogeneous networks. The basic idea is to enhance the performance of multicasting and broadcasting in heterogeneous network. The evaluation is done through extensive simulations conducted in QualNet 6.1 simulator.

The main idea of this paper is to propose an opportunistic multicast routing protocol with awareness of energy to adopt with the highly dynamic environment of Mobile Adhoc Network. The nodes spread in MANET environment is divided into several multicasting regions based on the geographical location. Each and every node is present in any one of the multicasting region. Each region is assigned with group address. When the source node forwards the data to a multicast group, the source node forwards the data through the node with highest power among the neighbor so, the proposed multicast routing scheme optimizes the total power consumption and increase the lifetime of the network. The performance is evaluated by comparing the results with the traditional method MAODV.

A mobile ad-hoc network (MANETs) is a wireless network of mobile nodes without any fixed base-station or any centralized administration. When a node sends a data packet to more than one node at a time, it is called multicasting, multicast often used to utilize the network resources like channel bandwidth and node energy to improve the network efficiency. Multicast in MANETs have several challenges due to frequent changes in the network such as node mobility, reliability, limited resources, etc. The MANETs is widely used in several fields like emergency searches, rescues operation, and military battlefields where sharing of information is mandatory. These operations often require a rapid deployable and quick reconfigurable routing protocols. Since mobile nodes in wireless ad-hoc network have limited resources so an efficient multicast routing protocol is needed to reduce the wastage of resources. This paper proposes a traffic load balanced multicast routing protocol (LBMRP) in order to reduce the network overhead and increases the network life. In this scheme all mobile nodes are randomly classified into multi group (three groups) and create a tree for each group in order to achieve efficient data transmission. Simulation results shows that the proposed LBMRP scheme outperforms with some existing multicast routing protocols as multicast ad-hoc on-demand distance vector routing protocol, reliability of the multicast ad-hoc on demand distance vector and Parallel multiple nearly-disjoint trees multicast routing schemes.

The explosion in mobile data traffic is a driver for future network operator technologies, given its large potential to affect both network performance and generated revenue. The concept of distributed mobility management (DMM) has emerged in order to overcome efficiency-wise limitations in centralized mobility approaches, proposing not only the distribution of anchoring functions but also dynamic mobility activation sensitive to the applications needs. Nevertheless, there is not an acceptable solution for IP multicast in DMM environments, as the first proposals based on MLD Proxy are prone to tunnel replication problem or service disruption. We propose the application of PIM-SM in mobility entities as an alternative solution for multicast support in DMM, and introduce an architecture enabling mobile multicast listeners support over distributed anchoring frameworks in a network-efficient way. The architecture aims at providing operators with flexible options to provide multicast mobility, supporting three modes: the first one introduces basic IP multicast support in DMM; the second improves subscription time through extensions to the mobility protocol, obliterating the dependence on MLD protocol; and the third enables fast listener mobility by avoiding potentially slow multicast tree convergence latency in larger infrastructures, by benefiting from mobility tunnels. The different modes were evaluated by mathematical analysis regarding disruption time and packet loss during handoff against several parameters, total and tunneling packet delivery cost, and regarding packet and signaling overhead.

Software-defined networking (SDN) has emerged as a promising network technology supporting the intelligent and dynamic nature of future networks and applications. Against this changing network landscape, the authors design an SDN-based, scalable multimedia multicast streaming framework, which optimizes multimedia flow management and provides scalability and flexibility. The proposed framework is capable of in-network identification, processing, and management of media streams. It implements network-layer multicast similar to IP multicast, but it allows admission control in a multicast context. An implemented prototype shows the proposed framework's possibilities and results.

Clos networks and their variations such as folded-Clos networks (fat-trees) have been widely adopted as network topologies in data center networks. Since multicast is an essential communication pattern in many cloud services, nonblocking multicast communication can ensure the high performance of such services. However, nonblocking multicast Clos networks are costly due to the large number of middle stage switches required. On the other hand, server redundancy is ubiquitous in today’s data centers to provide high availability of services. In this paper, we explore such server redundancy in data centers to reduce the cost of nonblocking multicast Clos data center networks (DCNs). To facilitate our analysis, we first consider an ideal fault-free data center with no server failure. We give an algorithm to assign active servers evenly among input stage switches in a multicast Clos DCN where each server has one or more redundant backups depending on the availability requirements of services they provide. We show that the sufficient nonblocking condition on the number of middle stage switches for a multicast Clos DCN can be significantly reduced by exploring server redundancy. Then, to complete our analysis, we consider a practical faulty data center, where one or more active servers may fail at any time. We give a strategy to re-balance the active servers among input stage switches after server failures so that the same nonblocking condition still holds. Finally, we provide a multicast routing algorithm with linear time complexity to configure multicast connections in Clos DCNs.

Wireless Mesh Network (WMN) presents us a key emerging technology which can construct the next generation wireless multi-hop network. It combines the advantages of both mobile ad-hoc network (MANET) and traditional fixed network. The applications of WMNs also attract significant industrial and academic attentions. As a vital function of network communication, multicast is normally applied to transmit data for high-definition video and gaming in WMNs. Therefore, the multicast routing algorithms are very important to the performance of group communication in WMNs. In this paper, we review a list of existing multicast routing algorithms in WMNs. Based on the findings, we also point out the open issues of multicast routing algorithms.

Device-to-device (D2D) multicast communication is a useful way to improve the communication efficiency of local services. In this paper, we study the power control of D2D multicast communication underlying cellular network. To improve the overall throughput of D2D and cellular communication, particle swarm optimization (PSO) algorithm based power allocation schemes are proposed under two scenarios. Firstly, we introduce a distributed controlled D2D multicast group formation procedure. And then, the system model of both D2D communication reuse the same frequency with one cellular user equipment (CUE) and with multi-CUEs is introduced. Under these two scenarios, the power allocation problems are transformed to constrained optimization problems. PSO algorithm is applied to get the solutions for optimization problems. Additionally, to get a compromise between fairness and the overall throughput of system, a new objective function with fairness factor is designed in the second scenario. Simulation results show that the proposed schemes significantly improve the throughput performance of system and guarantee the quality of both D2D and cellular communication.

We study energy-efficient multicast communication in multi-hop wireless networks.We present energy-efficient network model for multi-hop wireless networks.We exploit network coding idea to improve energy efficiency of networks.We propose the corresponding algorithm and perform detailed simulation analysis. Multi-hop multicast routing can provide better communication performance in multi-hop wireless networks. However, existing multi-hop multicast routing hardly take into account energy efficiency of networks. This paper studies the energy-efficient multicast communication aiming at multi-hop wireless networks. Firstly, we analyze energy metric and energy efficiency metric of multi-hop networks. Then the corresponding models are given. Secondly, network coding is used to improve network throughput. Different from previous methods, we here consider that network nodes are satisfied with a certain random distribution. In such a case, it is a challenge to construct the network structure that network coding requires. For the above random network topology, we propose three basic structures of network coding to overcome this problem. Thirdly, we present a flexible energy-efficient multicast routing algorithm for multi-hop wireless networks to extensively exploit the network structure proposed above to maximize network throughput and decrease network energy consumption. Finally, we perform numerical experiments by network simulation. Simulation results indicate that our approach is significantly promising.

We propose a network coding strategy for multicast applications called the simple network coding scheme, which takes network coding chances raised among adjacent nodes. The proposed scheme incorporates both intrasession and intersession network coding strategies and effectively improves multicast throughput. We characterize the capacity region of the proposed scheme and derive an optimal control algorithm for the proposed scheme. We perform a complexity analysis for the proposed control algorithm and provide some insights into its practical implementation. For a comparison, we also formulate the capacity region of conventional multicast schemes and provide performance evaluation using a linear programming solver. In empirical analyses, we investigate how the proposed scheme improves multicast throughput gains from various perspectives (i.e., the number of flows, the number of network coded packets, and split–multicast) and find out that most of the gains can be achieved by simple pairwise network coding with non-split–multicast. We observe dramatic throughput gains up to 75 $\%$ beyond the conventional schemes on random topologies with ten nodes.

Wireless multicast is a promising technology for delivering information from a server to multiple users. Through wireless multicast, the server can fulfill the data requirement of multiple users by simply transmitting a single copy of data contents, which increases the efficient usage of radio resources. This paper considers a multi-flow multicast scenario where a base station (BS) is capable of sending multiple data flows to multiple multicast groups. To configure the multicast and achieve optimal resource allocation, the BS may require the feedback of the channel-quality information (CQI) from the users. The CQI is, in general, the users' private information as only the users can directly measure their channel qualities. However, the selfish users may manipulate the multicast configuration through untruthful feedback to increase their own performance. Regarding this issue, we propose a multicast resource allocation mechanism with the designs of the pricing scheme and the weighted water-filling resource allocation. Our analysis shows that the proposed mechanism can elicit the true CQI from the users (strategy-proofness), avoiding any manipulation of multicast configuration and thereby guaranteeing efficient and fair network operation.

Recent advances in wavelength division multiplexing (WDM) networks have helped enhance the popularity of multicasting services. However, as a single network failure may disrupt the information transmission to multiple end-users, protecting multicast requests against network failures becomes an important issue in network operation. This paper investigates the sub-wavelength level protection for dynamic multicast traffic grooming. A new method named lightpath-fragmentation based segment shared protection (LF-SSP) scheme is proposed. By carefully splitting primary/backup lightpaths into segments to improve resource sharing for both traffic grooming and protection, LF-SSP aims to minimize the network resources allocated for request protection. Extensive simulations are carried out to compare the performance of LF-SSP to some existing approaches, on sub-wavelength-level as well as wavelength-level multicast protections in different cases. Results show that LF-SSP steadily outperforms these existing methods as long as the network resources are not too limited. Influences of the add/drop port resources and the average number of destinations per connection request on the LF-SSP performance are also evaluated. Accepted version

We study delivering delay-sensitive data to a group of receivers with minimum latency. This latency consists of the time that the data spends in overlay links as well as the delay incurred at each overlay node, which has to send out a piece of data several times over a finite-capacity network connection. The latter part is a significant portion of the total delay as we show in the paper, yet it is often ignored or only partially addressed by previous multicast algorithms. We analyze the actual delay in multicast trees and consider building trees with minimum-average and minimum-maximum delay. We show the NP-hardness of these problems and prove that they cannot be approximated in polynomial time to within any reasonable approximation ratio. We then present a set of algorithms to build minimum-delay multicast trees that cover a wide range of application requirements---min-average and min-max delay, for different scales, real-time requirements, and session characteristics. We conduct comprehensive experiments on different real-world datasets, using various overlay network models. The results confirm that our algorithms can achieve much lower delays (up to 60% less) and up to orders-of-magnitude faster running times (i.e., supporting larger scales) than previous related approaches.

Distributed relay scheme for wireless ad hoc multi-hop multicast network composed of low-power and low-complexity wireless devices with high density is proposed. The proposed relay scheme is shown to be better than flooding, which is the distributed relay scheme applied to ZigBee, in the outage probability and the multicast transmission rate by simulations.

The rise in multicast implementations has seen with it an increased support for fast failure recovery from link and node failures. Most recovery mechanisms augment additional services to existing protocols causing excessive overhead, and these modifications are predominantly protocol-specific. In this paper, we develop a multicast failure recovery mechanism that constructs protocol independent fast reroute paths to recover from single link and single node failures. We observe that single link failure recovery in multicast networks is similar to recovering unicast traffic, and we use existing unicast recovery mechanisms for multicast traffic. We construct multicast protection trees that provide instantaneous failure recovery from single node failures. For a given node x, the multicast protection tree spans all its neighbors and does not include itself. Thus, when the node fails, the neighbors of the node are connected through the multicast protection tree instead of node x, and forward the traffic over the multicast protection tree for the duration of failure recovery. The multicast protection trees are constructed a priori, without the knowledge of the multicast traffic in the network. Based on simulations on three realistic network topologies, we observe that the multicast protection trees increase the routing table size only by 38% on average and the path length between any source-destination pair by 13% on average.

At present, six low-power wireless personal area network uses the broadcasting in the link layer (L2) to achieve the multicast in the network layer (L3). Since broadcasting is expensive, this paper proposes a multicast scheme to achieve the L3 multicast with the L2 unicast. In this scheme, an L3 multicast message is transmitted to each member in a multicast group in the unicast way, so the multicast cost and delay are reduced. This paper also presents the handover algorithm to ensure that the multicast communication can be properly performed when the group members move. This paper evaluates the performance of this scheme, and the results show that this scheme effectively reduces the multicast cost and delay.

In this paper, we investigate a multisource multicast network with the aid of an arbitrary number of relays, where it is assumed that no direct link is available at each S-D pair. The aim is to find the fundamental limit on the maximal common multicast throughput of all source nodes if resource allocations are available. A transmission protocol employing the relaying strategy, i.e., compute-and-forward (CPF), is proposed. We also adjust the methods in the literature to obtain the integer network-constructed coefficient matrix (i.e., a naive method, a local optimal method, and a global optimal method) to fit the general topology with an arbitrary number of relays. Three transmission scenarios are addressed. The first scenario is delay-stringent transmission, where each message must be delivered within one slot. The second scenario is delay-tolerant transmission where no delay constraint is imposed. The associated optimization problems to maximize the short- and long-term common multicast throughputs are formulated and solved, and the optimal allocation of power and time slots are presented. The third case (a general $N$ -slot-delay-tolerant scenario) is also discussed, and a suboptimal algorithm is presented. Performance comparisons show that the CPF strategy outperforms conventional decode-and-forward (DF) strategy. It is also shown in the simulation that with more relays, the CPF strategy performs even better due to the increased diversity. Finally, by simulation, it is observed that, with CPF, the $N$ -slot-delay-constraint case can perform close to that of the delay-tolerant case in terms of throughput, given that $N$ is relatively large.

In order to support reliable medium access control (MAC) layer multicast services in Broadband Wireless Access (BWA) networks, we here propose spreading codes (Cumulative ACK (CA) code and ARQ Feedback Request (AFR) code) based reliable multicast feedback scheme. The status indications based on the automatic repeat request (ARQ) mechanism are needed in some multicast services. In accordance with various wireless channel environments, we demonstrate the performance excellency of our proposed scheme with respect to required uplink resources compared with the original feedback scheme based on unicast ARQ feedback messages. In addition, we analyze packet error rate (PER) against the various wireless channel environments.