The Experts below are selected from a list of 2484 Experts worldwide ranked by ideXlab platform
Robert Morris - One of the best experts on this subject based on the ideXlab platform.
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ExOR: Opportunistic multi-hop routing for wireless networks
2014Co-Authors: Sanjit Biswas, Robert MorrisAbstract:This paper describes ExOR, an integrated routing and MAC protocol that increases the throughput of large unicast trans-fers in multi-hop wireless networks. ExOR chooses each hop of a packet’s route after the transmission for that hop, so that the choice can reflect which intermediate nodes actually received the transmission. This deferred choice gives each transmission multiple opportunities to make progress. As a result ExOR can use long radio links with high loss rates, which would be avoided by traditional routing. ExOR in-creases a connection’s throughput while using no more net-work capacity than traditional routing. ExOR’s design faces the following challenges. The nodes that receive each packet must agree on their identities and choose one forwarder. The agreement protocol must have low overhead, but must also be robust enough that it rarely forwards a packet zero times or more than once. Finally, ExOR must choose the forwarder with the lowest remaining cost to the Ultimate Destination. Measurements of an implementation on a 38-node 802.11b test-bed show that ExOR increases throughput for most node pairs when compared with traditional routing. For pairs between which traditional routing uses one or two hops, ExOR’s robust acknowledgments prevent unnecessary retransmissions, increasing throughput by nearly 35%. For more distant pairs, ExOR takes advantage of the choice of forwarders to provide throughput gains of a factor of two to four
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a high throughput path metric for multi hop wireless routing
ACM IEEE International Conference on Mobile Computing and Networking, 2003Co-Authors: Douglas S J De Couto, Daniel Aguayo, John Bicket, Robert MorrisAbstract:This paper presents the expected transmission count metric (ETX), which finds high-throughput paths on multi-hop wireless networks. ETX minimizes the expected total number of packet transmissions (including retransmissions) required to successfully deliver a packet to the Ultimate Destination. The ETX metric incorporates the effects of link loss ratios, asymmetry in the loss ratios between the two directions of each link, and interference among the successive links of a path. In contrast, the minimum hop-count metric chooses arbitrarily among the different paths of the same minimum length, regardless of the often large differences in throughput among those paths, and ignoring the possibility that a longer path might offer higher throughput.This paper describes the design and implementation of ETX as a metric for the DSDV and DSR routing protocols, as well as modifications to DSDV and DSR which allow them to use ETX. Measurements taken from a 29-node 802.11b test-bed demonstrate the poor performance of minimum hop-count, illustrate the causes of that poor performance, and confirm that ETX improves performance. For long paths the throughput improvement is often a factor of two or more, suggesting that ETX will become more useful as networks grow larger and paths become longer.
Douglas S J De Couto - One of the best experts on this subject based on the ideXlab platform.
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a high throughput path metric for multi hop wireless routing
ACM IEEE International Conference on Mobile Computing and Networking, 2003Co-Authors: Douglas S J De Couto, Daniel Aguayo, John Bicket, Robert MorrisAbstract:This paper presents the expected transmission count metric (ETX), which finds high-throughput paths on multi-hop wireless networks. ETX minimizes the expected total number of packet transmissions (including retransmissions) required to successfully deliver a packet to the Ultimate Destination. The ETX metric incorporates the effects of link loss ratios, asymmetry in the loss ratios between the two directions of each link, and interference among the successive links of a path. In contrast, the minimum hop-count metric chooses arbitrarily among the different paths of the same minimum length, regardless of the often large differences in throughput among those paths, and ignoring the possibility that a longer path might offer higher throughput.This paper describes the design and implementation of ETX as a metric for the DSDV and DSR routing protocols, as well as modifications to DSDV and DSR which allow them to use ETX. Measurements taken from a 29-node 802.11b test-bed demonstrate the poor performance of minimum hop-count, illustrate the causes of that poor performance, and confirm that ETX improves performance. For long paths the throughput improvement is often a factor of two or more, suggesting that ETX will become more useful as networks grow larger and paths become longer.
Baldazzi Cristiana - One of the best experts on this subject based on the ideXlab platform.
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Mirror Images in al-Andalus: The Quest for Self-Identity in Two Arabic Travelogues
place:Trieste, 2020Co-Authors: Baldazzi CristianaAbstract:This essay aims to bring to light the approach to Spain that two Arab intellectuals, the Egyptian writer Ahmad Zaki (1867-1934) and the Lebanese painter Mustafa Farrukh (1901-1951), had in common. Both of them wrote a travelogue: Zaki\u2019s Rihla ila al-mu\u2019tamar was published in 1893 and Farrukh\u2019s Rihla ila bilad al-magd al-mafqud (was published in 1930. Zaki, in keeping with the methodology that was typical of the classical Arab travelogue (adab al-rihla), described all the European cities he visited on his way to his Ultimate Destination, the Congress of Oriental Scholars in London. On his return journey he stopped off in Spain which, he admitted unequivocally, was the country where he felt most at home. Farrouk, on the other hand, went directly to Spain to gather evidence on the artistic heritage that the Arabs had left in Andalusia. Despite the differences in their works, both these authors find in Spain a testimony to the ancient glory of its Muslim past, a fact which was in direct contrast to what they considered to be the general ignorance of other European countries at the same period. For both the authors, Spain was an example of the past greatness of Arabic civilization that belonged to the West as much as it did to the East and should, therefore, be considered by the Arabs as a means whereby they could emerge from the impasse of their decline. It was in the Other wich they found in Spain that they discovered themselves: they saw the Spaniards of their day as being similar to the Arabs because it was precisely to the latter that they were indebted for their own talent. They were, infact, a mirror image that both the authors could make work in the construction of the idea of a modern Arabic State
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Mirror Images in al-Andalus: The Quest for Self-Identity in Two Arabic Travelogues
EUT Edizioni Università di Trieste, 2020Co-Authors: Baldazzi CristianaAbstract:This essay aims to bring to light the approach to Spain that two Arab intellectuals, the Egyptian writer Aḥmad Zakī (1867-1934) and the Lebanese painter Muṣṭāfà Farrūkh (1901-1951), had in common. Both of them wrote a travelogue: Zakī’s Riḥla ilà l-mu’tamar was published in 1893 and Farrūkh’s Riḥla ilà bilād al-majd al-mafqūd (was published in 1930. Zakī, in keeping with the methodology that was typical of the classical Arab travelogue (adab al-rihla), described all the European cities he visited on his way to his Ultimate Destination, the Congress of Oriental Scholars in London. On his return journey he stopped off in Spain which, he admitted unequivocally, was the country where he felt most at home. Farrūkh, on the other hand, went directly to Spain to gather evidence on the artistic heritage that the Arabs had left in Andalusia. Despite the differences in their works, both authors find in Spain a testimony to the ancient glory of its Muslim past, a fact which was in direct contrast to what they considered to be the general ignorance of other European countries at the same period. For both the authors, Spain was an example of the past greatness of Arabic civilization that belonged to the West as much as it did to the East and should, therefore, be considered by the Arabs as a means whereby they could emerge from the impasse of their decline. It was in the Other which they found in Spain that they discovered themselves: they saw the Spaniards of their day as being similar to the Arabs because it was precisely to the latter that they were indebted for their own talent. They were, in fact, a mirror image that both authors could make work in the construction of the idea of a modern Arabic State
John Bicket - One of the best experts on this subject based on the ideXlab platform.
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a high throughput path metric for multi hop wireless routing
ACM IEEE International Conference on Mobile Computing and Networking, 2003Co-Authors: Douglas S J De Couto, Daniel Aguayo, John Bicket, Robert MorrisAbstract:This paper presents the expected transmission count metric (ETX), which finds high-throughput paths on multi-hop wireless networks. ETX minimizes the expected total number of packet transmissions (including retransmissions) required to successfully deliver a packet to the Ultimate Destination. The ETX metric incorporates the effects of link loss ratios, asymmetry in the loss ratios between the two directions of each link, and interference among the successive links of a path. In contrast, the minimum hop-count metric chooses arbitrarily among the different paths of the same minimum length, regardless of the often large differences in throughput among those paths, and ignoring the possibility that a longer path might offer higher throughput.This paper describes the design and implementation of ETX as a metric for the DSDV and DSR routing protocols, as well as modifications to DSDV and DSR which allow them to use ETX. Measurements taken from a 29-node 802.11b test-bed demonstrate the poor performance of minimum hop-count, illustrate the causes of that poor performance, and confirm that ETX improves performance. For long paths the throughput improvement is often a factor of two or more, suggesting that ETX will become more useful as networks grow larger and paths become longer.
Daniel Aguayo - One of the best experts on this subject based on the ideXlab platform.
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a high throughput path metric for multi hop wireless routing
ACM IEEE International Conference on Mobile Computing and Networking, 2003Co-Authors: Douglas S J De Couto, Daniel Aguayo, John Bicket, Robert MorrisAbstract:This paper presents the expected transmission count metric (ETX), which finds high-throughput paths on multi-hop wireless networks. ETX minimizes the expected total number of packet transmissions (including retransmissions) required to successfully deliver a packet to the Ultimate Destination. The ETX metric incorporates the effects of link loss ratios, asymmetry in the loss ratios between the two directions of each link, and interference among the successive links of a path. In contrast, the minimum hop-count metric chooses arbitrarily among the different paths of the same minimum length, regardless of the often large differences in throughput among those paths, and ignoring the possibility that a longer path might offer higher throughput.This paper describes the design and implementation of ETX as a metric for the DSDV and DSR routing protocols, as well as modifications to DSDV and DSR which allow them to use ETX. Measurements taken from a 29-node 802.11b test-bed demonstrate the poor performance of minimum hop-count, illustrate the causes of that poor performance, and confirm that ETX improves performance. For long paths the throughput improvement is often a factor of two or more, suggesting that ETX will become more useful as networks grow larger and paths become longer.
