Streaming market depth data: On what condition is quote data pushed?

prp

I want to execute trades based on (near) real-time analysis of market depth.
I want to know on which of the following conditions is quote data published on websocket?:

1. When market depth data changes
   
2. When an instrument is traded
   
3. When an instrument is traded and LTP changes?
   
4. Some other condition (please elaborate)
   
   

sujith

You can refer to websocket queries of FAQs.