Minecraft stops after a few minutes on my server

I wanted to play on my own server with my friends. Minecraft starts normaly and I can join the server but after a few minutes minecraft stops and I get a message that minecraft isn't working.

what I expected to happen was.....
that minecraft works and that I can play it

what actually happen was........
I can play for a few minutes but than it stops

steps to reproduce:
1. start minecraft
2. go to multiplayer and click on the server
3. Notice that I can play for a few minutes but that it stops and I get a message that minecraft isn't working