73,612 research outputs found
Influence of Input/output Operations on Processor Performance
Nowadays, computers are frequently equipped with peripherals that transfer great
amounts of data between them and the system memory using direct memory access
techniques (i.e., digital cameras, high speed networks, . . . ). Those peripherals prevent the
processor from accessing system memory for significant periods of time (i.e., while they
are communicating with system memory in order to send or receive data blocks). In this
paper we study the negative effects that I/O operations from computer peripherals have on
processor performance. With the help of a set of routines (SMPL) used to make discrete
event simulators, we have developed a configurable software that simulates a computer
processor and main memory as well as the I/O scenarios where the periph-erals operate.
This software has been used to analyze the performance of four different processors in four
I/O scenarios: video capture, video capture and playback, high speed network, and serial
transmission
Performance of Quantum Preprocessing under Phase Noise
Optical fiber transmission systems form the backbone of today's communication
networks and will be of high importance for future networks as well. Among the
prominent noise effects in optical fiber is phase noise, which is induced by
the Kerr effect. This effect limits the data transmission capacity of these
networks and incurs high processing load on the receiver. At the same time,
quantum information processing techniques offer more efficient solutions but
are believed to be inefficient in terms of size, power consumption and
resistance to noise. Here we investigate the concept of an all-optical joint
detection receiver. We show how it contributes to enabling higher baud-rates
for optical transmission systems when used as a pre-processor, even under high
levels of noise induced by the Kerr effect.Comment: 6 pages, 3 figures; To be published in IEEE GLOBECOM 2022, see this
https://globecom2022.ieee-globecom.or
Deep Space Network information system architecture study
The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control
Image Encryption using AES Encryption Technique with Bernoulli Chaotic Map
In last few years, the progress in communication technology has seen strong interest in digital picture or image transmission. However, computer processor growth in possessing power and storage illegal access has become easier. Encryption method involves some special mathematical algorithms and keys to transform digital data into cipher text or code before they are transmitted and decrypted method involves the application of mathematical algorithms and keys to obtain the original data from cipher text or code, scientific community have seen strong interest in image transmission. However, illegal image or data access has become more easy and established in wireless and general communication networks. Information privacy becomes a difficult issue. In order to protect, secure your valuable image or data from unauthorized readers, data or image encryption or decryption is essential, furthermore. As such in this paper, AES based on encryption has been proposed for secure image transmission over channels
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