Scan time

Today, the difference between PLCs and DCSs is becoming blurred. However, historically PLCs handled the bulk of digital inputs and outputs and the CPU scan time depends on the number of I/Os and the processing power. How do today's DCSs compare with PLCs in terms of the scan time given the same number of inputs and outputs both digital and analog?

There's processing time, and I/O scan/update time. Today, the I/O update time is usually the same, but the PLC scan time is still much much much faster.