This work introduces characteristics of twisted pair cables which play an important role in transferring data. In this paper, category 5 enhanced as a type of unshielded twisted pair cables was selected to verify all tests on it according to ISO/IEC 11801 as one of international standard specifications. Random samples were selected from cables market. All tests were done on these samples to make sure of using validity and complying with the international standard. After testing the selected samples, it is found that 4% are not satisfying the international standard specification while as 96% are satisfying the international standard specification.
{"title":"Performance testing of twisted pair cables","authors":"Ahmed F. Mahmoud, M. Abd-Allah","doi":"10.1155/2008/586427","DOIUrl":"https://doi.org/10.1155/2008/586427","url":null,"abstract":"This work introduces characteristics of twisted pair cables which play an important role in transferring data. In this paper, category 5 enhanced as a type of unshielded twisted pair cables was selected to verify all tests on it according to ISO/IEC 11801 as one of international standard specifications. Random samples were selected from cables market. All tests were done on these samples to make sure of using validity and complying with the international standard. After testing the selected samples, it is found that 4% are not satisfying the international standard specification while as 96% are satisfying the international standard specification.","PeriodicalId":45621,"journal":{"name":"Journal of Computer Networks and Communications","volume":"2008 1","pages":"4"},"PeriodicalIF":2.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2008/586427","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64175214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We consider a wireless ad hoc network with random access channel. We present a model that takes into account topology, routing, random access in MAC layer, and forwarding probability. In this paper, we focus on drawing benefit from the interaction of the MAC (governed by IEEE 802.11 or slotted Aloha) and routing by defining a new cross-layer scheme for routing based on the limit number of retransmission. By adjusting dynamically and judiciously this parameter in a saturated network, we have realized that both stability of forwarding queues and average throughput are significantly improved in linear networks with symmetric traffic: a gain of 100% can be reached. While in asymmetric topology network with asymmetric traffic, we achieve a better average delay (resp., throughput) for each connection without changing the average throughput (resp., delay). In addition, we show the efficiency of our new scheme in case of multimedia applications with delay constraint. A detailed performance study is presented using analytical and simulation evaluation.
{"title":"Dynamic retransmission limit scheme in MAC layer for routing in multihop ad hoc networks","authors":"Ralph El-Khoury, R. El-Azouzi","doi":"10.1155/2008/414073","DOIUrl":"https://doi.org/10.1155/2008/414073","url":null,"abstract":"We consider a wireless ad hoc network with random access channel. We present a model that takes into account topology, routing, random access in MAC layer, and forwarding probability. In this paper, we focus on drawing benefit from the interaction of the MAC (governed by IEEE 802.11 or slotted Aloha) and routing by defining a new cross-layer scheme for routing based on the limit number of retransmission. By adjusting dynamically and judiciously this parameter in a saturated network, we have realized that both stability of forwarding queues and average throughput are significantly improved in linear networks with symmetric traffic: a gain of 100% can be reached. While in asymmetric topology network with asymmetric traffic, we achieve a better average delay (resp., throughput) for each connection without changing the average throughput (resp., delay). In addition, we show the efficiency of our new scheme in case of multimedia applications with delay constraint. A detailed performance study is presented using analytical and simulation evaluation.","PeriodicalId":45621,"journal":{"name":"Journal of Computer Networks and Communications","volume":"2008 1","pages":"8"},"PeriodicalIF":2.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2008/414073","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64170383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：