Lag attacks

I was at my server right, and I was getting emeralds and my friends were at my server right. There is a lag attacking my server after the last emerald stage, I checked the ping and I said? Zipppeer, I was just typing fast and my server shuts down.

Whats going on here my server connection's maybe slow but how can I fix that.

Dude, I don't know if you know but I know that I know but well, do you know? It might depend on your connection or his connection. Or your computer simply JUST SUCKS!