User's Manual

Table Of Contents

Fig. 5.4: Router - Base driven, Addressing - Serial

5.2.2. Router - Flexible

Router mode with Flexible protocol is suitable for Multipoint networks of all topologies with unlimited

number of repeaters on the way, and all types of network traffic where Multi-master applications and

any combination of simultaneous polling and/or report-by-exception protocols can be used.

Each RipEX2 can access the Radio channel spontaneously using sophisticated algorithms to prevent

collisions when transmitting to the Radio channel. Radio channel access is a proprietary combination

of CSMA and TDMA; the Radio channel is deemed to be free when there is no noise, no interfering

signals and no frames being transmitted by other RipEX2 stations. In this situation, a random selection

of time slots follows and a frame is then transmitted on the Radio channel.

Frame acknowledgement, retransmissions and CRC check, guarantee data delivery and integrity even

under harsh interference conditions on the Radio channel.

5.2.2.1. Functionality example

In the following example, there are two independent SCADA devices connected to RipEX2's ports

(COM and ETH). One is designated RTU (Remote Telemetry Unit) and is assumed to be polled from

the centre by the FEP (Front End Processor). The other is labelled PLC (Programmable Logic Controller)

and is assumed to communicate spontaneously with arbitrary chosen peer PLCs.

RipEX2 in detail