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- Extended Performance Research on 5 GHz IEEE 802.11n WPA2 Laboratory LinksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioWireless communications by microwaves are increasingly important, e.g. Wi-Fi. Performance is a crucial issue, improving reliability and efficiency in communications. Security is also most important. Laboratory performance measurements are presented for Wi-Fi 5 GHz IEEE 802.11n WPA2 links. Our study contributes to performance evaluation of this technology under WPA2 encryption, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New results are given, namely for OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet length. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for point-to-point, point-to-multipoint and four-node point-to-multipoint links. Comparisons are also made to corresponding data obtained for Open links. Conclusions are drawn about performance of the links. © Springer Nature Singapore Pte. Ltd. 2019
- Performance Evaluation of 5 GHz IEEE 802.11n WPA2 Laboratory LinksPublication . Carvalho, Jose Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioThe increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a crucial issue, leading to more reliable and efficient communications. Security is also critically important. Laboratory measurements were performed about several performance aspects of Wi-Fi IEEE 802.11n WPA2 5 GHz links. Our study contributes to performance evaluation of this technology, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New detailed results are presented and discussed, namely at OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet length. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for both point-to-point and point-to-multipoint links. Comparisons are also made to corresponding results obtained for Open links. Conclusions are drawn about performance of the links.
- Extended Performance Research on IEEE 802.11a 54 Mbps Multi-Node Laboratory LinksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioWireless communications, involving electronic devices, are increasingly important Performance is a fundamental issue, leading to more reliable and efficient communications. Security is also most important. Laboratory measurements were performed about several performance aspects of Wi-Fi IEEE 802.11a 54 Mbps Open links. Our study contributes to performance evaluation of this technology, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New detailed results are given, namely at OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet length. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for point-to-point, point-to-multipoint and four-node point-to-multipoint links. Conclusions are drawn about performance of the links. © 2018, International Association of Engineers.
- A new performance assessment of 5 GHz IEEE 802.11n four-node point-to-multipoint linksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioThe performance of wireless communications is an essential point, leading to more trusty and efficacious communications. Security is also important. Laboratory experiments were performed on various performance points of Wi-Fi 5 GHz IEEE 802.11 n Open four-node point-to-multipoint links. Our study contributes to the performance assessment of this technology, utilizing accessible equipments (V-M200 access points from HP and WPC600N adapters from Linksys). New elaborated results are given and discussed, essentially at OSI levels 4 and 7, from TCP and UDP experiments: TCP throughput versus TCP packet size; jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to correspondent results from Open point-to-point links. Conclusions are taken about the comparative performance of the links. © 2017 Institute of Measurement Science SAS.
- Extended research on effects of encryption and topology on performance of IEEE 802.11a laboratory linksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioThe increasing importance of wireless communications, involving electronic devices, has been worldly recognized. Performance is an essential issue, leading to more reliable and efficient communications. Security is also critically important. Laboratory measurements were performed about several performance aspects of Wi-Fi IEEE 802.11a WPA2 and WPA point-to-multipoint links. Our study contributes to the performance evaluation of this technology, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New detailed results are presented and discussed, namely at OSI level 4, from TCP and UDP measurements: TCP throughput, jitter and percentage datagram loss. Comparisons are made to corresponding results obtained for WPA2 and WPA point-to-point, and Open links. Conclusions are drawn about the comparative performance of the links.
- Performance Evaluation of IEEE 802.11a 54 Mbps WEP Laboratory LinksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioThe increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, resulting in more reliable and efficient communications. Security is also crucially important. Laboratory measurements are presented about several performance aspects of Wi-Fi IEEE 802.11a 54 Mbps WEP point-to-point and point-to-multipoint links. Our study contributes to performance evaluation of this technology under WEP encryption, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New results are given from TCP and UDP experiments concerning TCP throughput versus TCP packet length, jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to corresponding results for Open links. Conclusions are drawn about the comparative performance of the links.
- Potentialities of low energy MeV nuclear techniques and computer simulation in surface analysis of materialsPublication . Carvalho, José Pacheco de; Pacheco, Cláudia Ribeiro; Reis, AntónioSurface analysis is made by nuclear, non-destructive, means and computer simulation for the energy method of analysis. The predicted energy spectra are compared to experimental data, giving target composition and concentration profile information. Mainly, target parameterization and available nuclear data are considered in the computations. The method is favourably applied to the determination of an 18O step concentration profile in a thick oxidized target. A uniform concentration profile of 12C is found for a thick target. Elastic scattering permits depth profiling of Al and O in a thick oxide target. © 2017 Institute of Measurement Science SAS.
- Performance Evaluation of IEEE 802.11a 54 Mbps WEP Multi-Node Laboratory LinksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioWi-Fi is an increasingly important wireless communication technique using microwaves. Performance is a very crucial issue, improving communication reliability and efficiency. Security is also most important. Laboratory performance measurements are presented for Wi-Fi IEEE 802.11 a 54 Mbps WEP multi-node links. Our study contributes to performance evaluation of this technology under WEP encryption, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). The paper gives new results from TCP and UDP experiments in terms of TCP throughput versus TCP packet length, jitter and percentage of datagram loss versus UDP datagram size. Comparisons are made with corresponding results for open links. Conclusions are drawn about the comparative performance of the links. © 2018 IEEE.
- Extended Performance research on IEEE 802.11 A 54 mbps WEP Laboratory LinksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioWireless communications by microwaves are increasingly important, e.g. Wi-Fi. Performance is a crucial issue, improving reliability and efficiency in communications. Security is also most important. Laboratory performance measurements are presented for Wi-Fi IEEE 802.11a WEP links. Our study contributes to performance evaluation of this technology under WEP encryption, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New results are given, namely for OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet size. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for point-to-point, point-to-multipoint and four-node point-to-multipoint links. Comparisons are also made to corresponding data obtained for Open links. Conclusions are drawn about the comparative performance of the links. © 2019 Springer Nature Singapore Pte Ltd
- Performance Evaluation of IEEE 802.11a 54 Mbps Open Laboratory LinksPublication . Carvalho, José Pacheco de; Veiga, Hugo; Pacheco, Cláudia Ribeiro; Reis, AntónioThe increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, leading to more reliable and efficient communications. Security is also critically important. Laboratory measurements were performed about several performance aspects of Wi-Fi IEEE 802.11a 54 Mbps Open links. Our study contributes to performance evaluation of this technology, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New detailed results are presented and discussed, namely at OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet length. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for both point-to-point and point-to-multipoint links. Conclusions are drawn about performance of the links.