Network Management System for Telecommunication and Internet Application

In a network management system (NMS) for broad band PLC a lot of different tasks and services must be integrated. The partly different requirements to data rate, transmission reliability and real time functionality must be met. The power-line is a very difficult transmission medium with limited channel capacity. To realise a reliable data transmission, a huge effort is necessary for modulation, equalisation and channel coding. Therefore, the NMS has to use the existing resources very efficiently. After discussion of the different options, we present a TDMA-System with resource-administration realised centrally in the master. Services for Broad Band PLC Currently, the most important service is internet access. This is a general term for several services with different requirements. On the one hand, www browsing requires a packet oriented data transmission with low real time requirements, but low acceptable bit error rate. On the other hand, voice-over-IP or web cast require connectionoriented services with high real-time requirements. A minimum quality of service must be guaranteed to allow commercial application. Experience shows that packet-oriented networks, such as Ethernet, can offer such services only if they are heavily overdimensioned and, therefore, utilise the channel very inefficiently. Another application is Broadband PLC for the last mile in telephony. This application requires a minimum quality of service, similar to the requirements of voice-over-IP, probably with even higher real-time requirements. Additional services, such as meter reading and home automation have low real-time and data requirements, but a large transmission range, which will most likely be difficult to achieve with broad band PLC, is necessary. To allow these requirements to be met using a channel with limited capacity, Quality of Service (QoS) parameters must be available. Efficient use of QoS is only possible if the backbone can also use the QoS data. This can be achieved by combi ig PLC with ATM. ATh4 is nowadays established as a standard in telecommunication and also for IP routers by CISCO. Block sizes and frame lengths have been taken into account in the NMS presented in this paper.