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This paper presents an analysis of new Dual Crosspoint Queued (DCQ) crossbar switch architecture. It is well-known that in order to achieve performance guarantees, the priority separation of incoming traffic is necessary. Therefore, we modified CQ crossbar switch with the separation of different traffic flows, by implementing two buffers in each crosspoint of switch fabric. Different round robin based scheduling algorithms are presented and analyzed. With the particular attention on the cell delay and cell loss probability, results of simulations show that proposed switch architecture can achieve desired QoS only for the high priority traffic flow. [ABSTRACT FROM PUBLISHER]

As an important radio resource management scheme in wireless cellular network, scheduling plays an important role in balancing the system throughput and user fairness. This paper studies the scheduling scheme in a special scenario, where the ordinary users and onboard high-speed train users are co-served by the same basestation (BS) in cellular network. Orthogonal frequency-division multiple-access (OFDMA)-based cellular communication systems such as the Third-Generation Partnership Project (3GPP) long-term evolution (LTE) is considered, thus the radio resources are scheduled in both frequency and time domains among different users. In the addressed scenario, it is shown that none of the max C/I, round robin (RR), proportional fair (PF) algorithms can provide good performance in terms of user fairness. Therefore, a new scheduling algorithm based on the original PF scheme is proposed, which not only improves the user fairness greatly but also causes no degradation to the system throughput. The performance of the proposed scheme is simulated and compared with other scheduling schemes in terms of both system throughput and user fairness. [ABSTRACT FROM PUBLISHER]

In embedded systems power consumption and area tightly constrain the cache capacity and management logic. Many good cache replacement policies have been proposed in the past, but none approach the performance of the least recently used (LRU) algorithm without incurring high overheads. In fact, many embedded designers consider even pseudo-LRU too complex for their embedded systems processors. In this paper, we propose a new level 1 (L1) data cache replacement algorithm, Protected Round-Robin (PRR) that is simple enough to be incorporated into embedded processors while providing miss rates that are very similar to the miss rates of LRU. Our experiments showed that on average the miss rates of PRR are only 0.22% higher than the miss rates of LRU on a 32KB, 4-way L1 data cache with 32 byte long cache lines. PRR has miss rates that are on average 4.72% and 4.66% lower than random and round-robin replacement algorithms, respectively. [ABSTRACT FROM PUBLISHER]

Infrastructure as a Service (IaaS) providers currently have no knowledge of the time frame customers intend to lease resources. However, scheduling in the absence of lease time information leads to wasted resources in times of decreasing demand. We explore how IaaS providers can use lease times to optimize resource allocation. We present two virtual machine scheduling algorithms to optimize the virtual-to-physical machine mapping taking lease time into account. Through simulation with synthetic and real-world workloads we evaluate the algorithms' potential to reduce the number of powered-up physical machines. Depending on data center size and request distribution the cumulative machine uptime is reduced by 28.4\% to 51.5\% when compared to round robin scheduling and by 3.3\% to 16.7\% when compared to first fit. Using a real-world workload from Google we achieve savings of 36.7\% and 9.9\% compared against round robin and first fit, respectively. [ABSTRACT FROM PUBLISHER]

Infrastructure as a Service Cloud system is based on virtualization technology to enables the hosting of massive number of computing resources. The efficient power management can help lower the cost of operating a large cloud substantially. Power usage in a cloud system depends largely on the system load and the proper use of physical machines. This paper proposes a new algorithm, Two Phases Power Convergence (TPCC) Algorithm that can be used to decrease the system power consumption substantially. This algorithm is based on the converging of the power usage to system utilization using 2 phases strategy - scaling phase and balancing phase. The implementation on our cloud system, Maekin, shows the result of lower power consumption as expected. The contribution of this work is a better understanding of workload management in cloud computing environment to achieve a good power consumption. This is very useful for the improvement of a cloud system resource utilization. [ABSTRACT FROM PUBLISHER]

Java Enterprise Edition or Java EE is one of the popular development platforms used for web applications and web services. In addition, critical business applications usually deploy a Java EE cluster for enhancing service performance and availability since the application workload has been increasing recently. This paper proposes a model to evaluate the performance of a Java EE cluster based on the characteristics of the TPC-H queries which are widely used for evaluating the performance of several databases. Each TPC-H query is characterized by the number of tables accessed, and its response time which is used as a guideline for balancing the workload on the Java EE cluster. The experimental results show that the proposed model gives better throughput than that of the typical Round Robin. [ABSTRACT FROM PUBLISHER]

Mechanism to support a massive number of machine-type-communication (MTC) devices in machine-to-machine (M2M) communication is crucial, because simultaneous concurrent transmission from massive MTC device yield in traffic congestion. This paper will tackle the congestion problem in Radio Access Network (RAN) that is happened in evolved Node-B (eNB) of Long Term Evolution (LTE) network. An adaptive mechanism to schedule the usage of radio resource is proposed, so that the congestion is alleviated. The mechanism ensures the network availability while targeting to maintain low delay and constant throughput. This mechanism facilitates devices to avoid continuous congestion in the next attempt of access. [ABSTRACT FROM PUBLISHER]

Providing efficient resource allocation in the grid computing is a major task. In this paper, a simple and proficient fuzzy based resource allocation algorithm is proposed that not only provides efficient allocation of resources but also ensures high utilization of the resources which are dynamic. The proposed technique constitutes of three different stages namely classification of grid resources, generation of fuzzy rules, and resource allocation based on those fuzzy rules. In the first stage, the grid resource is classified on the basis of dwelling time. In the second stage, the fuzzy rules are developed to allocate the resources to the particular job. In the third & final stage of the technique, the resources are allocated to the submitted jobs based on the generated fuzzy rules. The performance of the proposed algorithm is evaluated on the basis of utilization, failure rate and makespan, and is compared with conventional scheduling algorithms like First Come First Serve (FCFS), Round robin and Random. The results shows that the proposed fuzzy based resource allocation of resource and thereby improving the performance. [ABSTRACT FROM PUBLISHER]

A very common and typical problem faced by many big companies i.e. executing multiple projects at the same time. They have a huge pool of similarly skilled human resource (experts) which needs to be allocated to different projects with different payment rates. To allocate these resources to different projects such that there is not too much variation in their average compensation over a period of time means they get an equitable pay. The above problem is considered to be hard and no polynomial-time algorithm exists to solve this optimally. This paper concerns the development of innovative approach to solve the equitable payment distribution problem. The simple and foremost solution in adoption is round robin approach. This approach has a set of limitations. The problems which are constrained with equitable distribution objective finds round robin approach a non-suitable approach. For such problems to be solved optimally needs a novel approach to the equitable payment distribution. In this paper a Genetic Algorithm (GA) based novel approach has been proposed to find the optimal solution for the equitable payment distribution. [ABSTRACT FROM PUBLISHER]

Many papers focus on how to provide high performance for on-chip network. However, fewer papers have discussed fair resource allocation. In fact, global unfairness problem does exist in a network even if locally fair arbitration is adopted. In this paper, we propose Group Allocation to solve global unfairness problem. By controlling the timing to assert the allocation request, Group Allocation changes the service unit of allocation from packet to Group which takes one packet from every competing flow on an input port. In this way, router delivers one packet of every competing flow in an allocation round, so link bandwidth can be equally shared by competitors. Additionally, due to grouping, Group can be automatically adjusted based on the competition of flows. Hence, Group Allocation can be applied to various traffic patterns without prior knowledge of traffic patterns. Simulation results show Group Allocation is able to allocate bandwidth evenly and incur less impact on performance. In hotspot traffic case, the standard deviation of accepted throughputs under Group Allocation is 5.5179*10-6 flits/cycle and it is 0.0210 flits/cycle under round robin policy. It confirms Group Allocation reduces the difference of bandwidth usage among flows and allows resource allocation to be fair. [ABSTRACT FROM PUBLISHER]

Relay aided cellular network promises numbers of attractive performances such as cell-edge throughput improvement, fairness enhancement, higher throughput and etc, which is considered in Long-Term-Evolution-Advanced (LTE-A) standard. However, the promised advantages can only be achieved under proper co-channel interference control such as employing Fractional Frequency Reuse (FFR). To overcome the drawback of FFR, we propose a location-aided round robin scheduling algorithm in this paper, which allows the several carefully chosen frequencies to be reused among donor eNodeBs and relay nodes, so as to satisfy the fluctuation of traffic demand. [ABSTRACT FROM PUBLISHER]

Consistent hashing is known as a load balancing method for cases where a large number of requests are to be handled by multiple servers. However, if the frequencies of the requested keys, which are used for the hash calculation, are unbalanced, this causes an uneven distribution of the load to the servers. To solve this problem, this paper presents a load balancing method in which keys are classified into groups according to the frequency at which they are requested, and a different load balancing method is applied to each key group based on a single parameter. An evaluation of the proposed method using simulation has confirmed that the system can successfully balance the load with a reasonable number of commodity, low cost servers in cases where consistent hashing cannot be applied. [ABSTRACT FROM PUBLISHER]

Voice communication requires stricter QoS than other types of data communication. Thus, network operations, including the MAC layer protocol, should provide specific voice communication handling to meet voice application requirements. The current MIL-STD-188-220 does not guarantee the QoS of voice communication because of the round robin scheduling mechanism in network access control. Thus, we propose a hybrid MAC that provides adaptive virtual slots for voice messages on top of Deterministic Adaptable Priority Network Access Delay (DAP-NAD). In our proposed scheme, packet delay and jitter requirements of voice communication can be guaranteed, regardless of the number of stations in the network. Besides, the jitter tolerance time allows the other stations to adaptively transmit their data without disturbing voice communication and preserving data packet delay. The extensive simulation results show that the proposed scheme can guarantee quality of voice communication, regardless of network size. [ABSTRACT FROM PUBLISHER]

“Cloud computing” is a term, which involves virtualization, distributed computing, networking, software and web services. A cloud consists of several elements such as clients, datacenter and distributed servers. It includes fault tolerance, high availability, scalability, flexibility, reduced overhead for users, reduced cost of ownership, on demand services etc. Central to these issues lies the establishment of an effective load balancing algorithm. The load can be CPU load, memory capacity, delay or network load. Load balancing is the process of distributing the load among various nodes of a distributed system to improve both resource utilization and job response time while also avoiding a situation where some of the nodes are heavily loaded while other nodes are idle or doing very little work. Load balancing ensures that all the processor in the system or every node in the network does approximately the equal amount of work at any instant of time. This technique can be sender initiated, receiver initiated or symmetric type (combination of sender initiated and receiver initiated types). [ABSTRACT FROM PUBLISHER]

More and more data centers are built, consuming ever more kilo watts of energy. Over the years, energy has become a dominant cost factor for data center operators. Utilizing low-power idle modes is an immediate remedy to reduce data center power consumption. We use simulation to quantify the difference in energy consumption caused exclusively by virtual machine schedulers. Besides demonstrating the inefficiency of wide-spread default schedulers, we present our own optimized scheduler. Using a range of realistic simulation scenarios, our customized scheduler OptSched reduces cumulative machine uptime by up to 60.1%. We evaluate the effect of data center composition, run time distribution, virtual machine sizes, and batch requests on cumulative machine uptime. IaaS administrators can use our results to quickly assess possible reductions in machine uptime and, hence, untapped energy saving potential. [ABSTRACT FROM PUBLISHER]

With the introduction of 4th generation mobile networks, applications such as high-quality video streaming to the end user becomes possible. However, the expected demand for such services outpaces the capacity increase of the networks. Since there is mostly a capacity bottleneck in the air interface between a base station and user equipment, one of the main challenges for radio resource management is therefore to enforce precise quality guarantees for users with high expectations on service quality. We consider, in this paper, an OFDMA access network with YouTube users, and address the challenge of improving the quality of experience (QoE) of a dedicated user by utilizing the buffered playtime of a YouTube video for scheduling. The advantage of this approach is that scheduling is done according to the instantaneous throughput requirement of the end user application, and not by the network by maintaining average quality-of-service (QoS) parameters. The paper describes the concept and provides a simulative evaluation of the approach in an LTE network to demonstrate the benefits. [ABSTRACT FROM PUBLISHER]

The results of packet delay variation analysis for 32×32 crosspoint queued switch with unbalanced arrival traffic are presented in this paper. We analyzed switches with various buffer lengths for fixed-size packet lengths at switch inputs using several scheduling algorithms, i.e., longest-queue-first, round-robin, exhaustive-round-robin and frame-based-round-robin-matching. The results have shown that the round-robin algorithm gives the best performance among observed algorithms, considering delay variation. [ABSTRACT FROM PUBLISHER]

The widespread deployment of varying networking technologies, coupled with the exponential increase in end-user data demand, have all led to the proliferation of multi-homed or multi-interface enabled devices. To date, these interfaces are mainly utilized one at a time based on network availability, cost, and user-choice. Researchers have recently focused on leveraging these interfaces simultaneously by proposing solutions to aggregate their bandwidths in order to ultimately increase throughput and satisfy the end-user's growing demand on data. These solutions, however, have faced a steep deployment barrier due to various system design choices and heavy demand on energy. In this paper, we propose a novel Green and Deployable Bandwidth Aggregation System (G-DBAS) for multiple interface enabled devices. G-DBAS addresses a set of challenges including automatically estimating the characteristics of applications and scheduling various connections to different interfaces along with meeting different energy consumption goals set by users. We fully implement G-DBAS on the Windows OS and evaluate various scheduling strategies that we propose. Our implementation and simulation results show that G-DBAS can achieve the user energy-throughput goals while operating as an out-of-the-box standard Windows executable, highlighting its deployability and ease of use. [ABSTRACT FROM PUBLISHER]

Hydrophobic polymer insulators show higher contamination flashover voltages compared with ceramic insulators, but standard artificial contamination test methods have not yet been established. Test methods used for ceramic insulators are now usually used also for polymer insulators, but due to different surface properties and configurations between ceramic and polymer insulators, test procedures and conditions for ceramic insulators may not be pertinent for assessing polymer insulators. Under such circumstances, CIGRE WG C4.303 started round robin tests and results from four laboratories were presented but some differences were obtained. [ABSTRACT FROM PUBLISHER]

In this paper, a code division multiple access (CDMA) enabled dynamic bandwidth allocation (CDBA) algorithm is proposed for the upstream access scheme for Ethernet passive optical networks (EPON). The CDBA algorithm is based on two major components: The first is the parallel transmission capacity offered by CDMA according to the quality of service (QoS) requirement and the second component is the scheduling algorithm which uses the round robin technique. Extensive simulations have been performed in order to compare the proposed CDBA with existing dynamic bandwidth allocation (DBA) algorithms that achieve good bandwidth utilization by use of polling schemes. It is shown that the CDBA can significantly improve the network performance in terms of packet delay, throughput, and queue size management as compared with the well known IPACT algorithm. [ABSTRACT FROM PUBLISHER]

Process variations and device aging have a significant impact on the reliability and performance of nano scale integrated circuits. Proactive reconfiguration is an emerging technique to extend the lifetime of embedded SRAM memories. This work introduces a novel version that modifies and enhances the advantages of this method by considering the process variability impact on the memory components. Our results show between 30% and 45% SRAM lifetime increases over the existing proactive reconfiguration technique and between 1.7X and ∼10X improvement over the non-proactive reconfiguration. [ABSTRACT FROM PUBLISHER]

In recent years, much research attention has been paid to evolving self-learning game players. Fogel's Blondie24 is a demonstration of a real success in this field, inspiring many other scientists. In this paper, artificial neural networks are used as function evaluators in order to evolve game playing strategies for the game of checkers. We introduce a league structure into the learning phase of an individual and learning system based on the Blondie24 architecture. We show that this helps eliminate some of the randomness in the evolution. The best player we evolve is tested against an implementation of an evolutionary checkers program, and also against a player, which utilises the proposed round robin tournament and finally against an individual and social learning checkers program. The results are promising, suggesting many other research directions. [ABSTRACT FROM PUBLISHER]

This paper proposes the evaluation of LTE (Long Term Evolution) uplink performance using time and time-frequency domain Round Robin packet scheduling. In the analysis performed two types of non-real time services are considered, in both different and equal priorities cases. The number of users served in time-frequency domain packet scheduling strategy is limited by the number of PDCCHs (Physical Downlink Control Channel) and the results obtained take into account this constraint. Cell throughput, average user throughput and cell capacity are the performance indicators delivered by the simulations based on various scenarios of traffic, service priority and packet scheduling algorithms. [ABSTRACT FROM PUBLISHER]

This paper presents the results of the packet delay variation analysis for 32×32 crosspoint queued switch with uniform arrival traffic. Switches with various buffer lengths are analyzed using different scheduling algorithms: longest-queue-first, round-robin, exaustive-round-robin and frame-based-round-robin-matching. The results have shown that the round-robin algorithm has the least packet delay variation among the observed algorithms. [ABSTRACT FROM PUBLISHER]

NetFPGA is an open platform that enables rapid and efficient development and practical implementation of networking devices. On this platform we have implemented an originally designed Ethernet switch, based on a crossbar switching matrix with buffers at its crosspoints. In this paper we give an overview of the implemented switch design. We have carried out a number of tests of the switch in a real network environment. Based on the achieved results, we analyze the impact of the crosspoint buffers size on the packet loss probability inside the switching matrix, as well as the impact of the output buffers on the switch performance in general. [ABSTRACT FROM PUBLISHER]

The focus of this workshop paper is to show that highly constrained scheduling problems can be solved for business use using computational intelligence. We give detailed examples of school timetabling, sports scheduling and staff scheduling problems. The key components of a computational intelligence algorithm are discussed. [ABSTRACT FROM PUBLISHER]

Embedded systems designers are free to choose the most suitable configuration of L1 cache in modern processor based SoCs. Choosing the appropriate L1 cache configuration necessitates the simulation of long memory access traces to accurately obtain hit/miss rates. The long execution time taken to simulate these traces, particularly separate simulation for each configuration is a major drawback. Researchers have proposed techniques to speed up the simulation of caches with LRU replacement policy. These techniques are of little use in the majority of embedded processors as these processors utilize Round-robin policy based caches. In this paper we propose a fast L1 cache simulation approach, called SCUD(Sorted Collection of Unique Data), for caches with the Round-robin policy. SCUD is a single-pass cache simulator that can simulate multiple L1 cache configurations (with varying set sizes and associativities) by reading the application trace once. Utilizing fast binary searches in a novel data structure, SCUD simulates an application trace significantly faster than a widely used single configuration cache simulator (Dinero IV). We show SCUD can simulate a set of cache configurations up to 57 times faster than Dinero IV. SCUD shows an average speed up of 19.34 times over Dinero IV for Mediabench applications, and an average speed up of over 10 times for SPEC CPU2000 applications. [ABSTRACT FROM AUTHOR]

The upcoming generation of high accuracy synchrotron radiation (SR) optics will be characterized by a slope deviation from ideal shape in the range of some 0.05μrad rms at a sampling interval of about 1mm. To certify and improve the measurement capabilities of metrology tools to inspect these stringent specifications, an essential step is a worldwide intercomparison of these measurements based on a set of transfer standards. It is the aim of these cross measurements to verify the “absolute” correctness and comparability of the measurement results obtained by the cooperating partners when measuring the topography of specific reference optics (ROs) using their latest metrology tools and methods. Organized by members of the SR-optics community, new national and international cross measurement comparisons of typical synchrotron radiation mirrors have been realized during the last few years: A round robin test by the European COST-program (BESSY, Elettra, ESRF, Soleil) during the years 2004–2005 and a similar cooperation realized by the APS, ESRF and Spring-8 have proceeded. The first results of both projects were presented at the “Optics & Photonics” conference in San Diego in August 2005. This work build upon earlier work. The participants of both groups and representatives of other SR-laboratories agreed to start a global cooperation bringing together the two round-robin projects and open these activities to other partners from the SR-community, optical manufacturers and other interested parties. This initiative is intended to start an extensive comparison of various measurement principles and tools and will help to push the frontiers in metrology, and hence production, to a precision well below the current state-of-the-art limit of 0.5μrad rms for slope errors. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper presents a novel B-tree storage scheme that reduces the number of time-consuming erase operations on flash memory-based systems. The scheme adopts group-based round robin fashion and in-block logging technique for efficiently maintaining the B- tree nodes in the heavy-update workloads. Experimental results show that the proposed scheme improves the I/O performance by up to 3X , compared to the related work. [ABSTRACT FROM PUBLISHER]

Eligibility Based Round Robin (EBRR) scheduler proposed by Lenzini et al. is a packet scheduling algorithm which can be considered as an extension of Surplus Round Robin (SRR), computational complexity of which is O(1) even when quantum size is less than the maximum packet size. In this paper, we propose an extension of EBRR which makes it possible to transmit packets smaller than a threshold prior to packets larger than the threshold among packets received in one scheduling round. It can be used in Home Gateway. The computational complexity of the proposed algorithm is O(1). [ABSTRACT FROM PUBLISHER]

Performances of packet switch with buffers on input are given. Analyze of SLIP algorithm has done for following types of scenarios: different buffer capacity, different number of iteration, different acceleration. In addition, ideal case for fair allocation of recourse's and experimental results are given. [ABSTRACT FROM PUBLISHER]