Current Issue : July - September Volume : 2015 Issue Number : 3 Articles : 4 Articles
We present an optimization platform for Fiberto-\nthe-Home network design. The platform is capable of\nminimizing the capital expenditures (CAPEX) of network\ndeployment by optimizing locations of optical equipment,\nsignal splitters and cable cabinets, optimizing cable routes\nand types of cables as well as the number and types of optical\ncards and splitters. We present the architecture of the platform,\nthe design process it implements, and the algorithms\nit deploys. The platform is used to indicate the parts of the\ndesign process that require complex optimization with dedicated\nalgorithms and those that can be left to appropriately\ncrafted engineering rules. We indicate that while keeping\nthe computation time acceptable, much of the CAPEX savings\ncan be obtained when locations of optical equipment\nare thoroughly optimized, cable routes are determined with\nplain engineering rules, and finally, signal splitting patterns\nare optimized carefully to lower the fiber count and thus the\ncost of cables....
Wireless technologies are an essential communication\nmeans that transform a branched localized fixed\nmeshwork into a ubiquitous disconnected network. A clear\ntrend shows that cells are becoming smaller, homogeneously\ndistributed, operating at higher carrier frequencies, and\nmore energy conscious. This points toward wireless picocell\nsystems that implement millimeter-wave (mm-wave) modulation.\nIn this work various techniques are proposed, which\nare oriented to specific traits of the 60-GHz mm-wave band.\nTwo techniques oriented to solve physical and data-link layer\nissues are proposed. Single carrier frequency division multiple\naccess (SC-FDMA) is proposed as the technology to be\nimplemented at the physical layer, and a variable slot time\nmultiplexing access technique, called variable slot time-time\ndivision multiple access (VST-TDMA), with a conscious\nenergy-conservation protocol, is proposed for the data-link\n(MAC) layer. SC-FDMA with pulse shaping is implemented\nto minimize the peak-to-average power ratio of the system,\nwhich reduces energy consumption. The multiplexing\naccess technique takes advantage of the reduced cell size\nby multiplexing data in the time domain, this allows the\nreduced number of users to utilize the entire available bandwidth.\nIncorporated into the access protocol is the option of\nenergy pacing or even self-sustainability if an energy harvesting\ndevice is present. Self-sustainability can be achieved\nat the cost off throughput, some techniques are discussed to\nrelieve this trade-off condition. Also, a thorough discussion\nis included on battery energy depletion, even with an energy\nharvesting device present, to further increase the through- put performance. Since using SC-FDMA reduces the energy\nconsumption, it enables VST-TDMA to operate at higher\nspeeds under self-sustainability mode. Overall the proposed\nset of solutions showed independently significant improvements\nto the system. It is also discussed howthese techniques\ncoalesce conveniently by working in unison, improving the\nenergy efficiency and throughput capabilities of 60-GHz systems....
Overlay multicasting providing live streaming\nservices became crucial service in contemporary Internet. In\nthis paper, we focus on applying the overlay multicasting for\ndelivering of critical data that require to be transmitted safely,\nintact and with as little delay as possible. To improve survivability\nof the overlay multicasting, we propose to use dual\nhoming approach, i.e., each peer is connected to the overlay\nby two separate access links. We consider the following\nnetwork failures: overlay link failure, uploading node failure\nand ISP interconnection failure. The main goal of our\nexperiments is to determine the additional cost of providing\nsurvivability to the overlay multicasting network with dual\nhoming technology for both flow assignment and capacity\nand flow assignment problems. Our studies indicate that the\nadditional survivability requirements do not have a substantial\nimpact on the overlay multicasting system expressed as\nstreaming cost or network cost....
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