381 research outputs found
Quarc: a high-efficiency network on-chip architecture
The novel Quarc NoC architecture, inspired by the Spidergon scheme is introduced as a NoC architecture that is highly efficient in performing collective communication operations including broadcast and multicast. The efficiency of the Quarc architecture is achieved through balancing the traffic which is the result of the modifications applied to the topology and the routing elements of the Spidergon NoC. This paper provides an ASIC implementation of both architectures using UMCpsilas 0.13 mum CMOS technology and demonstrates an analysis and comparison of the cost and performance between the Quarc and the Spidergon NoCs
Quarc: a novel network-on-chip architecture
This paper introduces the Quarc NoC, a novel NoC architecture inspired by the Spidergon NoC. The Quarc scheme significantly outperforms the Spidergon NoC through balancing the traffic which is the result of the modifications applied to the topology and the routing elements.The proposed architecture is highly efficient in performing collective communication operations including broadcast and multicast. We present the topology, routing discipline and switch architecture for the Quarc NoC and demonstrate the performance with the results obtained from discrete event simulations
A performance model of multicast communication in wormhole-routed networks on-chip
Collective communication operations form a part of overall traffic in most applications running on platforms employing direct interconnection networks. This paper presents a novel analytical model to compute communication latency of multicast as a widely used collective communication operation. The novelty of the model lies in its ability to predict the latency of the multicast communication in wormhole-routed architectures employing asynchronous multi-port routers scheme. The model is applied to the Quarc NoC and its validity is verified by comparing the model predictions against the results obtained from a discrete-event simulator developed using OMNET++
A communication model of broadcast in wormhole-routed networks on-chip
This paper presents a novel analytical model to compute communication latency of broadcast as the most fundamental collective communication operation. The novelty of the model lies in its ability to predict the broadcast communication latency in wormhole-routed architectures employing asynchronous multi-port routers scheme. The model is applied to the Quarc NoC and its validity is verified by comparing the model predictions against the results obtained from a discrete-event simulator developed using OMNET++
Security and Privacy Issues in Wireless Mesh Networks: A Survey
This book chapter identifies various security threats in wireless mesh
network (WMN). Keeping in mind the critical requirement of security and user
privacy in WMNs, this chapter provides a comprehensive overview of various
possible attacks on different layers of the communication protocol stack for
WMNs and their corresponding defense mechanisms. First, it identifies the
security vulnerabilities in the physical, link, network, transport, application
layers. Furthermore, various possible attacks on the key management protocols,
user authentication and access control protocols, and user privacy preservation
protocols are presented. After enumerating various possible attacks, the
chapter provides a detailed discussion on various existing security mechanisms
and protocols to defend against and wherever possible prevent the possible
attacks. Comparative analyses are also presented on the security schemes with
regards to the cryptographic schemes used, key management strategies deployed,
use of any trusted third party, computation and communication overhead involved
etc. The chapter then presents a brief discussion on various trust management
approaches for WMNs since trust and reputation-based schemes are increasingly
becoming popular for enforcing security in wireless networks. A number of open
problems in security and privacy issues for WMNs are subsequently discussed
before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the
author's previous submission in arXiv submission: arXiv:1102.1226. There are
some text overlaps with the previous submissio
Implementation of Fuzzy Based Simulation for Clone Detection in Wireless Sensor Networks
Wireless sensor networks are usually left unattended and serve hostile environment, therefore can easily be compromised. With compromised nodes an attacker can conduct several inside and outside attacks. Node replication attack is one of them which can cause severe damage to wireless sensor network if left undetected. This paper presents fuzzy based simulation framework for detection and revocation of compromised nodes in wireless sensor network. Our proposed scheme uses PDR statistics and neighbor reports to determine the probability of a cluster being compromised. Nodes in compromised cluster are then revoked and software attestation is performed.Simulation is carried out on MATLAB 2010a and performance of proposed scheme is compared with conventional algorithms on the basis of communication and storage overhead. Simulation results show that proposed scheme require less communication and storage overhead than conventional algorithms
ECARDM: Energy Consumption Aware Route Discovery for Multicasting in Mobile Ad hoc Networks
Consideration of energy consumption in the case of wireless ad hoc networks leads to effective reduction of energy consumption by the nodes and increases the lifetime of the batteries for nodes. It is imperative from the existing models that there is significant scope for improvement in the energy-consumption based route discovery models. A model of Fuzzy based marginal energy disbursed multicast route discovery model for MANETs can support in reducing the power consumption has been proposed in our earlier research paper. In the present paper, a contemporary solution termed 201C;Energy Consumption Aware Route Discovery for Multicasting for MANETs201D; has been proposed, which is profoundly a fuzzy reasoning and genetic algorithm based model that focus on both the energy consumption and also the element of end-to-end delay whilst discovering the route. The experimental study of the model in comparison to BWDCMR and GAEEQMR models depicted that the proposed algorithm is very effective and can certainly be result oriented
Online Multicast Traffic Engineering for Software-Defined Networks
Previous research on SDN traffic engineering mostly focuses on static
traffic, whereas dynamic traffic, though more practical, has drawn much less
attention. Especially, online SDN multicast that supports IETF dynamic group
membership (i.e., any user can join or leave at any time) has not been
explored. Different from traditional shortest-path trees (SPT) and graph
theoretical Steiner trees (ST), which concentrate on routing one tree at any
instant, online SDN multicast traffic engineering is more challenging because
it needs to support dynamic group membership and optimize a sequence of
correlated trees without the knowledge of future join and leave, whereas the
scalability of SDN due to limited TCAM is also crucial. In this paper,
therefore, we formulate a new optimization problem, named Online Branch-aware
Steiner Tree (OBST), to jointly consider the bandwidth consumption, SDN
multicast scalability, and rerouting overhead. We prove that OBST is NP-hard
and does not have a -competitive algorithm for any
, where is the largest group size at any time. We
design a -competitive algorithm equipped with the notion of the
budget, the deposit, and Reference Tree to achieve the tightest bound. The
simulations and implementation on real SDNs with YouTube traffic manifest that
the total cost can be reduced by at least 25% compared with SPT and ST, and the
computation time is small for massive SDN.Comment: Full version (accepted by INFOCOM 2018
- …