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Quality of Service (QoS) mechanisms provide the necessary level of services (bandwidth and delay) to any application in order to maintain an expected quality level. This paper studies the effect of adopting QoS on the performance of (real time) system like video conferencing. A simulation model of the real time network is built using OPNET package. The various parameters affecting the system performance are determined and different solutions to enhance the system performance are suggested .A modified switch architecture is proposed to enhance the real time performance of the system and to modify its quality of service capability .The modification includes adding Etherchannel unit which can classify data into real time or non-real time data and direct each data packet to the appropriate channel .The architecture of the Etherchannel unit is described by VHDL programming and built on FPGA chip .Accordingly , the modified switch is found to need only extra seven clock pulses to classify each data packet .

The use of Kohonen self-organizing feature maps in real time applications requires high computational performance, especially for embedded systems and hence neural network chips are essential. A digital architecture of Kohonen neural network with learning capability and on-chip adaptation and storage is proposed with the implementation of Kohonen Self-Organizing Map (SOM) neural networks on the low-cost Spartan-3 FPGAs. The architecture of th i s di gi tal ch i p b ased on th e i dea th at som e assum pti on s f or th e restri cti on s of th e algorithm can simplify the implementation. Using the Manhattan distance, a special treatment of the adaptation factor, and neighborhood functions will decrease the necessary chip area so that a high number of processing elements can be integrated on one chip.

This paper studies Industrial Ethernet performance under different circumstances using the network simulation package(OPNET).It was assumed that industrial Ethernet is used to connect the different components of an electrical substation automation system. In the first simulation case, unicast transmission procedure is assumed. Unicast consumes CPU power and resources of the industrial node. In addition, if the packet production rate is high, queuing delay is created at different network layers of the industrial node. All this adds extra delay to the total value of the latency. Then, a comprehensive study to the effect of using multicasting was made. MulticastingNVLAN techniques are used to enhance the real time performance of industrial Ethernet by modifying packet generation process. Industrial nodes use multicasting technique to generate a packet forwarded to all members of a multicast group in the same time. Meanwhile, VLAN technique is used to forward the multicast traffic to its intended destinations only.

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