Multicast Data Packets Research Articles

An Accelerated End-to-End Probing Protocol for Narrowband IoT Medical Devices

In this study, a narrowband internet of things (NB-IoT) medical device (MD) was presented. We consider a wireless communication system where the multi-hop sources shared the downlink and uplink resources to probe and control hospital patients’ MDs.A multicast data packet was distributed over the multi-hop MD networks, and a random linear network coding approach was applied in the source instead of the intermediate nodes. We evaluated the MD probe cycle between a master station and remote terminal units, which were connected with several critical devices in a medical room. Furthermore, an accelerated end-to-end (E2E) probing protocol was established in the wireless mesh network to minimize the probing cycle of the health devices. In particular, a faster protocol was developed to address the probe and control subproblem.The proposed approach could assist in realizing the accelerated E2E probing for NB-IoT MDs, reducing the number of retransmissions, recovering lost packets, and providing a prompt overview of the medical network performance,based on several basic parameters such as modulation types, Quadrature amplitude modulation (QAM) and Frequency-shift keying (FSK), acknowledgment (ACK), average message sizes AMS, subcarrier spacing (SCS). Furthermore, in a comparative study of the contemporary probing cycle techniques, the proposed protocol notably outperformed several widely used protocols,with the reduction of the number of transmissions as well as the improvement of round trip time (RTT), and E2E probing cycle exceeding 89%, 71%, and 60%, respectively.

A Cooperative Peer-to-Peer Repair Scheme Based on Hybrid Network Coding

Cooperative peer-to-peer (P2P) repair (CPR) is an efficient way to recover the lost packets in wireless multicast system. Using network coding in CPR can further improve the transmission efficiency. However, there will be high computational overhead for random linear network coding and high optimization complexity for XOR-based network coding when the number of multicast data packet is relatively large. With regard to this problem, we propose a hybrid network coding based cooperative P2P repair scheme (HNC-CPR) with two efficient and light-weight scheduling algorithms. The HNC-CPR scheme can reduce the computational complexity while ensuring high transmission efficiency. Finally, example analyses and simulations demonstrate the efficiency and low-complexity of HNC-CPR.

A Scalable Destination-Oriented MulticastProtocol with Incremental Deployability

In this paper, we develop a scalable destination-oriented multicast (DOM) protocol for computer networks where the routers have enhanced intelligence to process packets. The basic idea of DOM is that each multicast data packet carries explicit destinations information, instead of an implicit group address, to facilitate the data delivery. Based on such destinations information, each router can compute necessary multicast copies and next-hop interfaces. A fundamental issue in DOM is to constrain the bandwidth overhead due to explicit addressing, which is tackled with a Bloom-filter based design. Our design incorporates the reverse path forwarding (RPF) concept and the BGP routing information, so that DOM can work efficiently in practical networking scenarios especially with asymmetric inter-domain routing. A critical issue in Bloom-filter based design is the issue of forwarding loop due to false positives. We propose an accurate tree branch pruning scheme, which equips the DOM the capability to completely and efficiently remove the false-positive forwarding loop. Furthermore, we study how the DOM can be deployed in an incremental manner over a network, in which only a small fraction of the routers have DOM-aware intelligence while others are legacy routers. We present extensive simulation results over a practical topology to demonstrate the performance of DOM, with comparison to the traditional IP multicast and the free riding multicast (FRM) protocols.

Reliable Buffering Management Algorithm Support for Multicast Protocol in Mobile Ad-hoc Networks

Multicasting is one of the relevant issues of communication in infrastructure or centralized administration networks. The reliable delivery of multicast data packets needs feedback from all multicast receivers to indicate whether a retransmission is necessary. A reliable multicast delivery in the wireless Ad-hoc network requires a multicast packet to be received by all multicast receiver nodes. Thus, one or all members need to buffer data packet for possible error recovery. Furthermore, different buffer strategies are essentially used in existing reliable multicast protocols towards support error recovery and reducing buffer overflow. This study proposed two algorithms to improve the performance of the source tree reliable multicast (STRM) protocol. The first algorithm was developed to avoid buffer overflow in the sender node as the forward server (FS) nodes of STRM. This reduction is achieved by managing the buffer of the FS nodes, i.e., selecting the FS nodes depending on its empty buffer size and reducing the feedback sent from the receiver nodes to their FS node. The second algorithm was developed to decrease duplicated packets in the multicast members of the local group, which may be achieved by sending the repair packets to the requesting member. The FS in the local group should create a dynamic and temporary subgroup whose members are only those that requested the repair packet retransmission. The algorithms were tested using detailed discrete event simulation models encompassing messaging systems including error, delay, and mobility models to characterize the performance benefits of the proposed algorithms compared with the existing wireless Ad-hoc network protocols. Several experiments were conducted, revealing numerous results that verify the superior performance of the proposed algorithms over the existing algorithms.

Prepare Tone: Enhancing Broadcast-Packet Transmission of Multiple Rendezvous Mac Performance in Multiple-Channel Ad Hoc Network

Multiple Rendezvous approaches utilized multi-channel which was only with a single transceiver radio may enhance Mac throughputs of multi-channel ad hoc network no less than that of other approaches which need extra radios or hardware for time synchronization. However, for the media-access methods of Multiple Rendezvous, nodes in ad hoc network should be listening on different channels to preserve the control packets of any data transmission with noneinterference each other. Therefore, for any broadcast data packet or multicast data packet, it should be transmitted to its destinations like a set of single-cast data packets. And then other performances of ad hoc network as routing may be reduced by the high overload of broadcast packet. In order to reduce the transmission number of a broadcast packet, a method of using prepare tones (single-cast tone and broadcast tone) before data-packet transmission is presented, we called it PTMC (Prepare Tone for Media-access Control). In the method of PTMC, any broadcast packet will be send out only once to preserve it can reach any idle destination, which is not sending or receiving any data-packets at that time, nevertheless any single-cast packet will be matched and send out just as MAXM done. Simulation results among PTMC, MAXM and SSCH show: If every broadcast packet was send to potential receivers one by one, the throughputs of ad hoc network routed by AODV and media controlled by MAXM or SSCH may not be improved as the available channel number is increasing, for reasons of the routing discovery time increasing. Using PTMC to solve this problem, whatever data-traffics or available channels are provided, the throughput of PTMC will be better than the other two. Thus with available channels increasing, the throughput of PTMA is improved.

An Intelligent Multicast Ad-hoc On demand Distance Vector Protocol for MANETs

Recently multicast ro uting protocols in Mobile Ad-hoc Networks (MANETs) are emerging for wireless group communication. This includes application such as multipoint data dissemination and multiparty conferencing which made the analytical design and development of the MANETs in a very efficient manner. For MANETs there are several multicast routing protocols are available, but they perform well under specific scenarios only. The topology of a MANET changes adequately based on the random mobility of network nodes, unlike the network topology of a wired network which is static. Multicast routing protocol outperforms the basic broadcast routing by sharing the resources along general links, while sending information to a set of predefined multiple destinations in a concurrent way. Due to the lack of redundancy in multipath and multicast structures, the multicast routing protocols are vulnerable to the component failure in ad-hoc networks. So it is the dire need to solve the problem optimally. One of the efficient techniques for solving the optimization problem is the Genetic Algorithm (GA). The key factors that determine the performance of GA is by the well designed architecture of chromosomes and operators in the intelligent algorithm. This paper proposes a new genetic algorithm based Multicast Ad-hoc On demand Distance Vector Protocol for MANETs (GA-MAODV), which improves the packet delivery ratio of the routing messages. The GAbased MAODV allows each node in the network to send out multicast data packets, and the multicast data packets are broadcast when propagating along the multicast group tree.

FI-Based Local Group Key Generation/Distribution for Mobile Multicast in a Hierarchical Mobile IPv6 Network

In order to securely transmit multicast data packets in a mobile environment where frequent join/leave events are a characteristic of the environment, there is a need for a new secure and efficient group key management solution. We propose a secure group key generation/distribution solution providing scalability and reliability. Using this solution, when a mobile node, which is in a multicast session, enters a new domain, the agent of the domain joins the multicast session and coordinates its data packets with the mobile node. The agent encrypts and transmits subsequent data packets to the mobile node, using a local one-time pad key. This key is generated with FI sequences, enabling the mobile node to regenerate the same data packet, based on the information sent by the agent. Our performance analysis demonstrates that the proposed solution can significantly reduce the number of key generations and distributions, when it is applied to the hierarchical mobile IPv6 network.

A Fast and Efficient Explicit Multicast Routing Protocol

The state-oriented design of IP multicast may lead to the scalability problem, especially when there is a very large number of concurrent multicast groups in the network. Motivated by this problem, explicit multicast offers a stateless design using header space of multicast data packets. In this paper, we propose a novel stateless scheme called Linkcast that efficiently eliminates processing overhead of explicit multicast protocols. In Linkcast, the multicast sender encodes the tree listing its links in a proper way. The tree code is sent with every multicast data packet. Simulation results and experiments with real-trees show that Linkcast completely eliminates processing overhead of other explicit multicast protocols such as Xcast with comparable header size overhead.

Network tomography from aggregate loss reports

Multicast applications and network monitors can potentially benefit from the ability to infer the loss rates along links within a multicast tree. Estimators, known generically by minc or multicast inference of network characteristics, have been developed to provide this ability. They consider multicast data packets to be probes, and conduct inference based upon reports of which probes reached each receiver. In practice, gathering reports from receivers in real time is a non-trivial task that presents scaling problems as the number of receivers increases. Prior work has led to an extension of the RTP data transport protocol to permit receivers to report per-probe information in packets known as RTCP XR packets. This paper demonstrates how minc inference can, in fact, be conducted using only a default RTP packet format known as RTCP RR. RTCP RR packets contain summary information rather than per-probe information. They thus offer bandwidth savings, although this comes at the expense of an increase in estimator convergence time. Furthermore, this technique can be used by the observer of any standard RTP session, whereas estimation based upon per-probe information is only possible when a session explicitly employs the extended reporting format.

Next Branch Multicast (NBM) routing protocol

It is well known that IP multicast suffers from deployment issues. The problem mainly originates from the multicast routing complexities in the inter-domain level and state-full nature of current solutions. To cope with the problem, many alternative group communication methods have been proposed. Among them, branching point (BP) based approaches have promising features like incremental deployment, high tree availability, low memory requirement and, hence, high scalability. However, current BP-based methods suffer from two major inefficiencies namely the tree construction difficulties and presence of excessive lookups in the forwarding process of unicast and multicast data packets. We propose a new BP-based protocol named NBM (Next Branch Multicast) to avoid the existing drawbacks. NBM constructs the multicast distribution tree in the forward direction and has a fault-detection and repair mechanism which protects the tree against BPs failures. NBM detects the failure of a higher level BP in the tree sooner than a lower level BP. NBM does not maintain any type of control state in non-branching routers. Our simulation results show that NBM memory requirement for maintaining multicast forwarding states is approximately less than half when compared to the traditional approach. In addition, the NBM tree is more available than the traditional one at least by a factor of 2.

Multicast Communication in Ad Hoc Networks with Directional Antennas

This paper investigates the benefits and impacts of using directional antennas for multicast communications in ad hoc networks. In terms of signal reception, directional antennas have shown considerable improvement in the performance of all aspects over omni-directional antennas, especially over dense networks with heavy traffic load. In addition, we have found that transmitting multicast packets directionally to known neighboring group members or forwarders can help reduce the average end-to-end packet delay and increase the overall throughput. However, directional transmission of unacknowledged data transfers may result in lower performance in terms of packet delivery ratio than omni-directional transmission in any carrier sensing MAC protocols under moderate load due to the effect from the hidden terminal problem. Both analytical results and simulation results, as well as an acknowledgment mechanism to improve the successful delivery rate of multicast data packets, are presented.

Optimal Time Slot Assignment Algorithm for Combined Unicast and Multicast Packets

This paper considers a packet-scheduling al- gorithm for a given combined traffic of unicast and multicast data packets and proposes a hybrid router with several dedi- cated buses for multicast traffic. Our objective is to develop a scheduling algorithm that minimizes schedule length for the given traffic in the hybrid router. We derive a lower bound and develop an optimal solution algorithm for the hybrid router.

Transmission range effects on AODV multicast communication

As laptop computers begin to dominate the marketplace, wireless adapters with varying bandwidth and range capabilities are being developed by hardware vendors. To provide multihop communication between these computers, ad hoc mobile networking is receiving increasing research interest. While increasing a node's transmission range allows fewer hops between a source and destination and enhances overall network connectivity, it also increases the probability of collisions and reduces the effective bandwidth seen at individual nodes. To enable formation of multihop ad hoc networks, a routing protocol is needed to provide the communication and route finding capability in these networks. The Ad hoc On-Demand Distance Vector Routing protocol (AODV) has been designed to provide both unicast and multicast communication in ad hoc mobile networks. Because AODV uses broadcast to transmit multicast data packets between nodes, the transmission range plays a key role in determining the performance of AODV. This paper studies the effects of transmission range on AODV's multicast performance by examining the results achieved at varying transmission ranges and network configurations.