Redundancy Out of the Box - VTS has the ability to share data over a network as one of its out-of-the-box capabilities.

One PC on the network can be designated as a data server for a particular PLC, and the remaining PCs on the network can act as clients. This means that only the server PC actually communicates with the PLC. This Server can, and normally does, function as any other operator station. It is not restricted to just being a data concentrator as with other HMI's, and can switch to becoming a client in fail-over scenarios. The remaining clients all get their data for that PLC from the server PC. This limits the communication to each PLC, vastly improving communication updates. VTS also allows for redundancy in its data servers. A list of backup data servers can be assembled such that, if the first data server drops off of the network the second data server, which could be a client, automatically picks up the server responsibility. This can be continued with a second backup data server and so on. This arrangement produces efficient data propagation and can be arranged in a variety of network paths such as a star node or ring. It is has been used in some cases to provide a redundancy level of 28 backup servers.