Development and performance evaluation of highly efficient retransmission scheme for high-speed data transfer via satellite

1990 ◽  
Vol 73 (6) ◽  
pp. 99-108
Author(s):  
Tsutomu Nakamura ◽  
Ryooichi Sasaki ◽  
Nobuyuki Fujikura ◽  
Hiroshi Morita
2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Sicong Wang ◽  
Chen Wei ◽  
Yuanhua Feng ◽  
Hongkun Cao ◽  
Wenzhe Li ◽  
...  

AbstractAlthough photonics presents the fastest and most energy-efficient method of data transfer, magnetism still offers the cheapest and most natural way to store data. The ultrafast and energy-efficient optical control of magnetism is presently a missing technological link that prevents us from reaching the next evolution in information processing. The discovery of all-optical magnetization reversal in GdFeCo with the help of 100 fs laser pulses has further aroused intense interest in this compelling problem. Although the applicability of this approach to high-speed data processing depends vitally on the maximum repetition rate of the switching, the latter remains virtually unknown. Here we experimentally unveil the ultimate frequency of repetitive all-optical magnetization reversal through time-resolved studies of the dual-shot magnetization dynamics in Gd27Fe63.87Co9.13. Varying the intensities of the shots and the shot-to-shot separation, we reveal the conditions for ultrafast writing and the fastest possible restoration of magnetic bits. It is shown that although magnetic writing launched by the first shot is completed after 100 ps, a reliable rewriting of the bit by the second shot requires separating the shots by at least 300 ps. Using two shots partially overlapping in space and minimally separated by 300 ps, we demonstrate an approach for GHz magnetic writing that can be scaled down to sizes below the diffraction limit.


2005 ◽  
Vol 50 (12) ◽  
pp. 2065-2069 ◽  
Author(s):  
R. Marquez ◽  
E. Altman ◽  
S. Sole-Alvarez

2007 ◽  
Vol 1054 ◽  
Author(s):  
Ruth Houbertz ◽  
Herbert Wolter ◽  
Volker Schmidt ◽  
Ladislav Kuna ◽  
Valentin Satzinger ◽  
...  

ABSTRACTThe integration of optical interconnects in printed circuit boards (PCB) is a rapidly growing field worldwide due to a continuously increasing need for high-speed data transfer. There are any concepts discussed, among which are the integration of optical fibers or the generation of waveguides by UV lithography, embossing, or direct laser writing. The devices presented so far require many different materials and process steps, but particularly also highly-sophisticated assembly steps in order to couple the optoelectronic elements to the generated waveguides. In order to overcome these restrictions, an innovative approach is presented which allows the embedding of optoelectronic components and the generation of optical waveguides in only one optical material. This material is an inorganic-organic hybrid polymer, in which the waveguides are processed by two-photon absorption (TPA) processes, initiated by ultra-short laser pulses. In particular, due to this integration and the possibility ofin situpositioning the optical waveguides with respect to the optoelectronic components by the TPA process, no complex packaging or assembly is necessary. Thus, the number of necessary processing steps is significantly reduced, which also contributes to the saving of resources such as energy or solvents. The material properties and the underlying processes will be discussed with respect to optical data transfer in PCBs.


2012 ◽  
Vol 229-231 ◽  
pp. 1543-1546
Author(s):  
Xiao Bo Zhou ◽  
Min Xia ◽  
Hai Long Cheng

To improve data transmission performance of the data acquisition card, a design of high-speed data transmission system is proposed in the thesis. Using FPGA of programmable logic devices, adopting Verilog HDL of hardware description language, the design of modularization and DMA transmission method is implemented in FPGA. Eventually the design implements the data transmission with high-speed through PCI Express interface. Through simulation and verification based on hardware system, this design is proved to be feasible and can satisfy the performance requirements of data transmission in the high-speed data acquisition card applied in high-speed railway communication. The design also has some value of application and reference for a universal data acquisition card.


2021 ◽  
Vol 21 (4) ◽  
pp. 1-23
Author(s):  
Bin Yuan ◽  
Chen Lin ◽  
Deqing Zou ◽  
Laurence Tianruo Yang ◽  
Hai Jin

The rapid development of the Internet of Things has led to demand for high-speed data transformation. Serving this purpose is the Tactile Internet, which facilitates data transfer in extra-low latency. In particular, a Tactile Internet based on software-defined networking (SDN) has been broadly deployed because of the proven benefits of SDN in flexible and programmable network management. However, the vulnerabilities of SDN also threaten the security of the Tactile Internet. Specifically, an SDN controller relies on the network status (provided by the underlying switches) to make network decisions, e.g., calculating a routing path to deliver data in the Tactile Internet. Hence, the attackers can compromise the switches to jeopardize the SDN and further attack Tactile Internet systems. For example, an attacker can compromise switches to launch distributed denial-of-service attacks to overwhelm the SDN controller, which will disrupt all the applications in the Tactile Internet. In pursuit of a more secure Tactile Internet, the problem of abnormal SDN switches in the Tactile Internet is analyzed in this article, including the cause of abnormal switches and their influences on different network layers. Then we propose an approach that leverages the messages sent by all switches to identify abnormal switches, which adopts a linear structure to store historical messages at a relatively low cost. By mapping each flow message to the flow establishment model, our method can effectively identify malicious SDN switches in the Tactile Internet and thus enhance its security.


2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Wenqi Chen ◽  
Hui Tian ◽  
Chin-Chen Chang ◽  
Fulin Nan ◽  
Jing Lu

Cloud storage, one of the core services of cloud computing, provides an effective way to solve the problems of storage and management caused by high-speed data growth. Thus, a growing number of organizations and individuals tend to store their data in the cloud. However, due to the separation of data ownership and management, it is difficult for users to check the integrity of data in the traditional way. Therefore, many researchers focus on developing several protocols, which can remotely check the integrity of data in the cloud. In this paper, we propose a novel public auditing protocol based on the adjacency-hash table, where dynamic auditing and data updating are more efficient than those of the state of the arts. Moreover, with such an authentication structure, computation and communication costs can be reduced effectively. The security analysis and performance evaluation based on comprehensive experiments demonstrate that our protocol can achieve all the desired properties and outperform the state-of-the-art ones in computing overheads for updating and verification.


2009 ◽  
Vol 17 (1-2) ◽  
pp. 43-57 ◽  
Author(s):  
Michael Kistler ◽  
John Gunnels ◽  
Daniel Brokenshire ◽  
Brad Benton

In this paper we present the design and implementation of the Linpack benchmark for the IBM BladeCenter QS22, which incorporates two IBM PowerXCell 8i1processors. The PowerXCell 8i is a new implementation of the Cell Broadband Engine™2 architecture and contains a set of special-purpose processing cores known as Synergistic Processing Elements (SPEs). The SPEs can be used as computational accelerators to augment the main PowerPC processor. The added computational capability of the SPEs results in a peak double precision floating point capability of 108.8 GFLOPS. We explain how we modified the standard open source implementation of Linpack to accelerate key computational kernels using the SPEs of the PowerXCell 8i processors. We describe in detail the implementation and performance of the computational kernels and also explain how we employed the SPEs for high-speed data movement and reformatting. The result of these modifications is a Linpack benchmark optimized for the IBM PowerXCell 8i processor that achieves 170.7 GFLOPS on a BladeCenter QS22 with 32 GB of DDR2 SDRAM memory. Our implementation of Linpack also supports clusters of QS22s, and was used to achieve a result of 11.1 TFLOPS on a cluster of 84 QS22 blades. We compare our results on a single BladeCenter QS22 with the base Linpack implementation without SPE acceleration to illustrate the benefits of our optimizations.


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