I have been using Pusher for some time now. I always assumed "Real time" meant "instantaneous". Lately I have step into this article: https://en.wikipedia.org/wiki/Real-time_computing, and a sentence grab my attention:
"Real-time programs must guarantee response within specified time constraints"
They give an example based on audio processing:
"Consider an audio DSP example; if a process requires 2.01 seconds to analyze, synthesize, or process 2.00 seconds of sound, it is not real-time. However, if it takes 1.99 seconds, it is or can be made into a real-time DSP process."
My questions: 1. This definition only applies to hardware/electronic devices or can be applied to software too? 2. If applies to software, does it apply to remote services like Pusher? 3. What is the time constraint for pusher to be considered "Real time"? 4. What is the time constraint for other services like WebRTC, Firebase?