146722
Adaptive dissemination of dynamic information services in an extended data broadcast environment
Considering that most information broadcast services generate data dynamically in practice, we devise in this paper an extended data broadcast mechanism which supports not only the original data broadcast scenario but also the dissemination of dynamic inforamtion services. Furthermore, we design an on-line loan-based slot allocation and feedback technique to tolerate the dynamic changes of broadcast traffic and accordingly perform the adaptation of service classification, bandwidth allocation and broadcast schedule so as to enhance the performance. Our experimental studies show that the extended data broadcast mechanism associated with the loan-based feedback technique is able to achieve a substantial saving in message traffic for dynamic information dissemination in wireless networks.
20310851
A mobile agent-based active network architecture for intelligent network control
The innovation and evolution of network technologies and services to enhance network functionality have traditionally encountered the problems of backward-compatibility and standardization. To resolve the related issues, active networks have been introduced to enable specific customization of network functionality without the lengthy standard-mediated committee processes. In this paper, we exploit the capability of mobile agent technology to construct an active network architecture. We argue that the mobile agent can be a building block for specific network customizations, and introduction of new network functionality. Both integrated and discrete operational models of network customizations can be supported in our prototype implementation. For the service development and deployment, an abstract service structure and a service loading mechanism are presented. Furthermore, we provide an agent management/control mechanism and devise a service management/control mechanism, which is either not available or incomplete in the other related work. The proposed architecture allows new service introduction, and as a result, achieves improved network functionality.
863906
Per-Flow Queueing by Dynamic Queue Sharing
Per-flow queuing is believed to be able to guarantee advanced Quality of Service (QoS) for each flow. With the dramatic increase of link speed and number of traffic flows, per-flow queuing faces a great challenge since millions of queues need to be maintained for implementation in a traditional sense. In this paper, by setting only a small number of physical queues, we propose a Dynamic Queue Sharing (DQS) mechanism to achieve an equal performance to the pure per-flow queuing with a lower cost. The proposed mechanism is based on an interesting fact that the number of simultaneous active flows in the router buffer is far less than that of in-progress flows. In DQS, a physical queue is dynamically created on-demand when a new flow comes and then dynamically released when the flow temporarily pauses. Hashing and binary sorting tree (or linked list) are combined to manage the mapping between flows and queues, so as to isolate flows in different queues. Theoretical analysis and traces experiments are conducted to evaluate DQS. The results demonstrate that when the parameters are well set, the operation delay is less than two time cycles in average with an extra memory of 16k bits.
44360962
Parallel Solution of the Poisson-Boltzmann Equation for Proteins
A fortran code PBSOLVE is created for numerical solution of a linear Poissson-Boltzman equation. Finite difference discretization and successive overrelaxation (SOR) iterations on the sequence of grids are used to obtain the approximate electrostatic potential on the grid. Error control is provided by comparison of solution on nested grids. A parallel versioon of the PBSOLVE which exploits the message passing interface (MPI) has also been constructed. The performances of the program and the efficiency of parallelization have been tested on the small peptide Met-Enkephalin.
7704531
A TCAM-based distributed parallel IP lookup scheme and performance analysis
Using ternary content addressable memory (TCAM) for high-speed IP address lookup has been gaining popularity due to its deterministic high performance. However, restricted by the slow improvement of memory accessing speed, the route lookup engines for next-generation terabit routers demand exploiting parallelism among multiple TCAM chips. Traditional parallel methods always incur excessive redundancy and high power consumption. We propose in this paper an original TCAM-based IP lookup scheme that achieves both ultra-high lookup throughput and optimal utilization of the memory while being power-efficient. In our multi-chip scheme, we devise a load-balanced TCAM table construction algorithm together with an adaptive load balancing mechanism. The power efficiency is well controlled by decreasing the number of TCAM entries triggered in each lookup operation. Using four 133 MHz TCAM chips and given 25% more TCAM entries than the original route table, the proposed scheme achieves a lookup throughput of up to 533 MPPS while remains simple for ASIC implementation
14245590
RED with optimized dynamic threshold deployment on shared buffer
Prior survey of RED algorithm deployment on multiqueue system with shared buffer was unfair and sensitive to congestion level by statically setting the parameters. In this paper, our goal is to deploy the Random Early Detection (RED) algorithm in routers on shared buffer and solve these problems. A novel buffer management scheme that dynamically adjusts the parameters of RED named RED-ODT is proposed. Simulations under uniform traffic load and nonuniform traffic load are given, the results of which ascertain and demonstrate the superiority of the proposed scheme in terms of low packet drop ratio, satisfying buffer utilization and fairness. Simulation also shows that RED-ODT is insensitive to congestion level.
206440147
Berkeley reliability tools-BERT
Berkeley reliability tools (BERT) simulates the circuit degradation (drift) due to hot-electron degradation in MOSFETs and bipolar transistors and predicts circuit failure rates due to oxide breakdown and electromigration in CMOS, bipolar, and BiCMOS circuits. With the increasing importance of reliability in today's and future technology, a reliability simulator such as this is expected to serve as the engine of design-for-reliability in a building-in-reliability paradigm. BERT works in conjunction with a circuit simulator such as SPICE in order to simulate reliability for actual circuits, and, like SPICE, acts as an interactive tool for design. BERT is introduced and the current work being done is summarized. BERT is used to study the reliability of a BiCMOS inverter chain, and performance data are presented. >