Analysis and Design of a Modern SCADA System

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  1. 9 Improving System Reliability Using a Standby WirelessMesh
    Network (WMN)
    In this thesis a standby WMN network is used as a redundancy
    method in the event of any wiring, redundant paths, and dual links failure.
    Wireless networks could be used to keep the network services alive until
    fixing the wiring system. The designed work in this case involves the wise
    selection of wireless standard and WMNs routing protocol, then
    transmitting powerand received powerestimation. DSR is one of WMNs
    protocol which is chosen for transferring FTP files from network
    substationsto the central station (Mosul400) with minimum delay, packets
    loss, and response time.

  2. 9 .1Object Configuration:
    The objects in the environment are nodes, server, application, and
    profile. The application configuration object is used in configuring the
    types of application used and the packet length. The profile application
    object is used to group applications configured in the application object
    into a profile; i.e. an FTP profile is the profile created in the profile object
    and configured to support FTP application created in the application object.
    The FTP profile is then configured in all nodes except the destination node.

  3. 9 .2 Transmit Power Estimation:
    In order to estimate the proper value of transmission power of
    each substation, it was found out that, OPNET Modeler uses the following
    formula to calculate the transmit power of a wireless node:


푃= 4 휋퐿퐷 ²∗ 10 −^12.^5 ........................................................ ( 3 - 22 )


Where D is the transmission range in meters and P is the transmit power,
and L is the wavelength lambda of the packet transmission. This formula is
used when operating at 11Mbps 802.11b and -95dbm as the received power

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