Tài liệu Network Segmentation

A PLC access network can be realized to include a whole low-voltage power supply
network or to include only a part of a supply network. To reduce the number of users
per PLC system and the network length, it is possible to divide the low-voltage network
into several parts (e.g. one PLC system per network section). In this case, several PLC
systems can work simultaneously in a low-voltage network. Fig. 3.4 presents a possible
segmentation of the low-voltage supply network that consists of three network sections.
Each network section has a base station that connects a number of subscribers of a
separated PLC access network. So, there are three separate PLC access systems within
the low-voltage network. In this way, the number of subscribers who share the available
network capacity is reduced.
One result of the network segmentation in multiple PLC access systems is a reduced
length of originated PLC networks operating in individual network sections. Accordingly,
the transmission can be realized with a lower signal power, which is important because
of the electromagnetic compatibility problem (EMC, Sec. 2.4.2, Sec. 3.3). There are also
a smaller number of potential subscribers in a network section than in the whole supply
network and the transmission capacity is shared by a smaller number of PLC subscribers.
The network segmentation is not limited only to network sections/branches. Each part of
a supply network could also be realized as a separate PLC access system. It causes a
further decrease in network length and in the number of subscribers connected to a PLC
access network. It can be concluded that individual PLC systems within a low-voltage
network also keep the physical tree topology