The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Mario Gerla - One of the best experts on this subject based on the ideXlab platform.

  • cognitive Multicast cocast in vehicular networks using ofdm subchannels and network coding
    2012 International Conference on Computing Networking and Communications (ICNC), 2012
    Co-Authors: Wooseong Kim, Brian Sung Chul Choi, Mario Gerla
    Abstract:

    The deployment of wireless Multicast in vehicular networks using the ISM band is challenging due to the interference from residential WiFi users. Recently developed cognitive radio techniques can help overcome such interference, with spectrum sensing and multi-channel assignment. CoCast is a cognitive multi-channel Multicast Protocol originally designed for the urban environment under the assumption that channels are orthogonal. In fact, Wi-Fi channels in the 2.4-GHz ISM band are partially overlapped. In this paper, we remodel the CoCast Protocol to handle the more realistic environment where channels are overlapped in frequency. The main challenge is the adjacent channel interference, the effect of which is mitigated in CoCast by employing two techniques: 1) parallel frame transmission over OFDM subchannels, and 2) network coding. Our evaluation shows that the reliability of Multicast communication among vehicles in a dense urban environment can be significantly improved with these Protocol extensions.

  • codecast a network coding based ad hoc Multicast Protocol
    IEEE Wireless Communications, 2006
    Co-Authors: Joonsang Park, Mario Gerla, Desmond S Lun, Muriel Medard
    Abstract:

    In this article we present CodeCast, a network-coding-based ad hoc Multicast Protocol. CodeCast is especially well-suited for multimedia applications with low-loss, low-latency constraints such as audio/video streaming. The key ingredient of CodeCast is random network coding, which transparently implements both localized loss recovery and path diversity with very low overhead. Simulation results show that in a typical setting, CodeCast yields a nearly 100 percent delivery ratio, as compared to a 94 percent delivery ratio by traditional Multicast. More importantly, the overhead is reduced by as much as 50 percent

  • team oriented Multicast a scalable routing Protocol for large mobile networks
    Lecture Notes in Computer Science, 2003
    Co-Authors: Mario Gerla, Joonsang Park, Dario Maggiorini
    Abstract:

    This paper proposes a Multicast Protocol, called Team Oriented Multicast (TOM). TOM builds up a “motion aware” hierarchy to support efficient, scalable team Multicast Protocol. TOM identifies clusters of nodes with same affinity as teams and manages the Multicast membership information using the unit of team rather than dealing with individual node members. TOM uses a two-tier data dissemination approach where the source propagates a data packet to each subscribed team’s leader and each leader forwards the data to the entire team. TOM constructs a Multicast mesh structure among leaders of subscribed teams, where each leader is connected to m other parent leaders, receiving duplicate packet streams from each parent. Each team leader proactively maintains the list of nodes in the same Multicast mesh.

  • a performance comparison study of ad hoc wireless Multicast Protocols
    International Conference on Computer Communications, 2000
    Co-Authors: Sungju Lee, Mario Gerla, Julian Hsu, Rajive Bagrodia
    Abstract:

    In this paper we investigate the performance of Multicast routing Protocols in wireless mobile ad hoc networks. An ad hoc network is composed of mobile nodes without the presence of a wired support infrastructure. In this environment, routing/Multicasting Protocols are faced with the challenge of producing multihop routes under host mobility and bandwidth constraints. In recent years, a number of new Multicast Protocols of different styles have been proposed for ad hoc networks. However, systematic performance evaluations and comparative analysis of these Protocols in a common realistic environment has not yet been performed. In this study, we simulate a set of representative wireless ad hoc Multicast Protocols and evaluate them in various network scenarios. The relative strengths, weaknesses, and applicability of each Multicast Protocol to diverse situations are studied and discussed.

  • Forwarding Group Multicast Protocol (FGMP) for multihop, mobile wireless networks
    Cluster Computing, 1998
    Co-Authors: Ching–chuan Chiang, Mario Gerla, Lixia Zhang
    Abstract:

    In this paper we propose a new Multicast Protocol for multihop mobile wireless networks. Instead of forming Multicast trees, a group of nodes in charge of forwarding Multicast packets is designated according to members' requests. Multicast is then carried out via “scoped” flooding over such a set of nodes. The forwarding group is periodically refreshed to handle topology/membership changes. Multicast using forwarding group takes advantage of wireless broadcast transmissions and reduces channel and storage overhead, thus improving the performance and scalability. The key innovation with respect to wired Multicast schemes like DVMRP is the use of flags rather than upstream/downstream link state, making the Protocol more robust to mobility. The dynamic reconfiguration capability makes this Protocol particularly suitable for mobile networks. The performance of the proposed scheme is evaluated via simulation and is compared to that of DVMRP and global flooding.

Ritesh Jain - One of the best experts on this subject based on the ideXlab platform.

  • a secure Multicast Protocol with copyright protection
    ACM Special Interest Group on Data Communication, 2002
    Co-Authors: Lintian Qiao, Klara Nahrstedt, Hua Wang, Ritesh Jain
    Abstract:

    We present a simple, efficient, and secure Multicast Protocol with copyright protection in an open and insecure network environment. There is a wide variety of multimedia applications that can benefit from using our secure Multicast Protocol, e.g., the commercial pay-per-view video Multicast, or highly secure military intelligence video conference. Our secure Multicast Protocol is designed to achieve the following goals. (1) It can run in any open network environment. It does not rely on any security mechanism on intermediate network switches or routers. (2) It can be built on top of any existing Multicast architecture. (3) Our key distribution Protocol is both secure and robust in the presence of long delay or membership message. (4) It can support dynamic group membership, e.g., JOIN/LEAVE/EXPEL operations, in a network bandwidth efficient manner. (5) It can provide copyright protection for the information provider. (6) It can help to identify insiders in the Multicast session who are leaking information to the outside world. We have implemented a prototype system which validates our secure Multicast Protocol and evaluated it against various performance matrices. The experimental results are very encouraging, but also show where new engineering approaches need to be deployed to conform fully to the design goals.

Wendi B. Heinzelman - One of the best experts on this subject based on the ideXlab platform.

  • Stateless Multicast Protocol for Ad Hoc Networks
    IEEE Transactions on Mobile Computing, 2012
    Co-Authors: Chen-hsiang Feng, Yuqun Zhang, Ilker Demirkol, Wendi B. Heinzelman
    Abstract:

    Multicast routing Protocols typically rely on the a priori creation of a Multicast tree (or mesh), which requires the individual nodes to maintain state information. In dynamic networks with bursty traffic, where long periods of silence are expected between the bursts of data, this Multicast state maintenance adds a large amount of communication, processing, and memory overhead for no benefit to the application. Thus, we have developed a stateless receiver-based Multicast (RBMulticast) Protocol that simply uses a list of the Multicast members' (e.g., sinks') addresses, embedded in packet headers, to enable receivers to decide the best way to forward the Multicast traffic. This Protocol, called Receiver-Based Multicast, exploits the knowledge of the geographic locations of the nodes to remove the need for costly state maintenance (e.g., tree/mesh/neighbor table maintenance), making it ideally suited for Multicasting in dynamic networks. RBMulticast was implemented in the OPNET simulator and tested using a sensor network implementation. Both simulation and experimental results confirm that RBMulticast provides high success rates and low delay without the burden of state maintenance.

Saurabh Bagchi - One of the best experts on this subject based on the ideXlab platform.

  • lrrm a randomized reliable Multicast Protocol for optimizing recovery latency and buffer utilization
    Symposium on Reliable Distributed Systems, 2005
    Co-Authors: N Malhotra, S Ranjan, Saurabh Bagchi
    Abstract:

    An efficient recovery Protocol for lost messages is crucial for supporting reliable Multicasting. The tree-based recovery Protocols group nodes into recovery regions and designate a recovery node per region for buffering and retransmitting lost messages. In these Protocols, the recovery host may get overloaded during periods of large message losses and costly remote recovery may be initiated even though a peer node has the lost message. To address these drawbacks, the randomized reliable Multicast Protocol (RRMP) was proposed which distributes the responsibility of error recovery among all members in a group. The pressure on the buffer and computational resources on the intermediate nodes is increasing due to the wide distribution of Multicast participants with widely varying reception rates and periodic disconnections. In this paper, we propose the lightweight randomized reliable Multicast (LRRM) Protocol that optimizes the amount of buffer space by providing an efficient mechanism based on best-effort Multicast for retrieving a lost message. A theoretical analysis and a simulation based study of two realistic topologies indicate that LRRM provides comparable recovery latency to RRMP for lower buffer space usage. While presented in the context of RRMP, LRRM can also benefit other tree-based reliable Multicast Protocols.

  • failure handling in a reliable Multicast Protocol for improving buffer utilization and accommodating heterogeneous receivers
    Pacific Rim International Symposium on Dependable Computing, 2004
    Co-Authors: G Khanna, Saurabh Bagchi, J Rogers
    Abstract:

    Reliable Multicast Protocols are an important class of Protocols for reliably disseminating information from a sender to multiple receivers in the face of node and link failures. A tree-based reliable Multicast Protocol (TRAM) provides scalable reliable Multicast by grouping receivers in hierarchical repair groups and using a selective acknowledgment mechanism. We present an improvement to TRAM to minimize the resource utilization at intermediate hosts and to localize the effect of slow or malicious receivers on normal receivers. We present an evaluation of TRAM and TRAM++ on a campus-wide WAN without errors and with message errors. The evaluation brings out that, given a constraint on the buffer availability at intermediate hosts, TRAM++ can tolerate the constraint at the expense of increasing the end-to-end latency for the normal receivers by only 3.2% compared to TRAM in error-free cases. When slow or faulty receivers are present, TRAM++ is able to provide the same uninterrupted quality of service to the normal nodes while localizing the effect of the faulty ones without incurring any additional memory overhead.

Saumitra Mohan Das - One of the best experts on this subject based on the ideXlab platform.

  • high throughput Multicast routing metrics in wireless mesh networks
    International Conference on Distributed Computing Systems, 2006
    Co-Authors: Sabyasachi Roy, Dimitrios Koutsonikolas, Saumitra Mohan Das
    Abstract:

    The stationary nature of nodes in a mesh network has shifted the main design goal of routing Protocols from maintaining connectivity between source and destination nodes to finding high-throughput paths between them. In recent years, numerous link-quality-based routing metrics have been proposed for choosing high-throughput paths for unicast Protocols. In this paper we study routing metrics for high-throughput tree or mesh construction in Multicast Protocols. We show that there is a fundamental difference between unicast and Multicast routing in how data packets are transmitted at the link layer, and accordingly there is a difference in how the routing metrics for each of these primitives are designed. We adapt certain routing metrics for unicast for high-throughput Multicast routing and propose news ones not previously used for high-throughput. We then study the performance improvement achieved by using different link-quality-based routing metrics via extensive simulation and experiments on a mesh network testbed, using ODMRP as a representative Multicast Protocol. Our testbed experiment results show that ODMRP enhanced with linkquality routing metrics can achieve up to 17.5% throughput improvement as compared to the original ODMRP.