Which server would be the best at receiving/sending ~10kb messages from/to ~100 different sources every second ?
Essentially I'm looking for the best ping.
None of those will give you ping improvements because ping depends on your network. if what you want is less overhead then use Jnetwork and UDP (expect only negible performance improvements)
if you want a lightweight protocol with very small footprint try mqtt.
What is MQTT? "MQTT is a Client Server publish/subscribe messaging transport protocol. It is light weight, open, simple, and designed so as to be easy to implement. These characteristics make it ideal for use in many situations, including constrained environments such as for communication in...