  Smart manufacturing has the objective of creating highly flexible and
resource optimized industrial plants. Furthermore, the improvement of product
quality is another important target. These requirements implicate more complex
control algo-rithms. Processing these algorithms may exceed the capabilities of
resource constrained devices, such as programmable logic controllers (PLCs). In
this case, the necessity for computation offloading is given. Due to the fact
that industrial plants are currently designed for a life-cycle-time of more
than ten years, in a realistic smart manufacturing scenario, these devices have
to be considered. Therefore, we investigate the impact of complex algorithms on
conventional PLCs by simulating them with a load generator. In addition, we
propose a realistic factory scenario including benchmarks for both wireline and
wireless communication systems. Thus, their round-trip time (RTT) is measured
with and without additional load on the network. With the help of these
investigations, break-even points for the application of computation offloading
of two typical PLCs of Siemens S7 series can be calculated.
