use the same protocol as RS232 to avoid doubling up
use the TCP/IP transport not UDP so that the connected control system can be certain that messages have been received.
do not use WOL to wake the thing up. This is a complete pain for integrators/programmers having to know the MAC address of the unit. The MAC address needs to be kept either hard coded in the program (bad) or in a configuration file that can be read at program startup (better). If the unit has to be replaced for whatever reason, then the integrator cannot simply swap the unit out – either the programming or the configuration file needs to be modified as well which costs time and money which can rarely be recouped.