03-08-2015, 07:34 PM
I wiin need afull projectreport of ATM on-line monitoring system
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atm networks for online monitoring system pdf
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I wiin need afull projectreport of ATM on-line monitoring system
08-03-2017, 12:08 PM
A low-cost ATM monitoring system, hosted by a standard PC. The monitor can be used remotely. Return information about ATM traffic flows to a central site. The monitor is connected to a GPS timing receiver, which provides absolute time accuracy of better than 1 ms. By tracking the same traffic flow at different points in a network, it is possible to measure the cellular delay and the variation of delay in real time, and with the existing traffic. The monitoring system characterizes the cells by means of a CRC calculated on the payload of the cell, so no special measurement cells are required. Delays in local area and wide area networks have been measured using this system. It is possible to measure the delay in a network that is not ATM end-to-end, as long as some cells remain identical at the entry and exit points. Examples of traffic and delay measurements are given on wide area and local network systems, including delays measured via the Internet from Canada to New Zealand.
At present, measuring the performance of wide area ATM networks is a complex and costly business requiring a cost of equipment in the region of $ 100,000 installed at each monitoring site. Traditional methods of network performance monitoring also depend on the introduction of measurement cells in the network, which disturbs the same conditions being measured. This paper describes a low-cost, non-invasive method for measuring traffic flow, cell delay, variation of cell delay and cell loss in ATM networks, including geographically large networks. It is also possible to perform delay measurements on non-ATM end-to-end networks, such as the Internet, if the ATM over ATM encapsulation is the same at both ends of the measured portion of the network. The technique requires the installation of PC-based ATM monitors at network measurement sites, and each monitor returns information about the cells it receives back to a central analysis site. If this information return flow can be taken to a separate network, then the measurement process itself does not impose additional traffic on the network being measured. The non-invasive method of measuring cellular delay depends on the correlation of traffic at different sites by identifying individual cells in existing traffic. The measurement systems calculate a CRC on the payload of each ATM cell received. This acts as a cell signature, which does not change as the cell moves through the network. If these cell signatures and arrival times are returned to a central site, the cell flows can be matched and the time delay calculated for each adapted cell.
![[Image: image10.gif]](http://wand.net.nz/pubs/27/html/images/image10.gif)
The precise clock required for measuring cellular delay is provided by a GPS time receiver at each measurement site. These receivers have a time precision (relative to UTC) of approximately 100 nsec, and cost less than $ 1,000 per unit. Figure 1 shows a general diagram of the remote monitoring system.
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