Networking Example

I found a few tutorials on a basic echo server/client where you can send text from the client to the server and the server will echo your text back.

The code is very simple and I feel as though merely communicating between two machines won't be hard. The problem I foresee is if we're already having trouble with the number of entities on screen, will we be able to still run the game at an optimal speed if the program will have to continuously send and receive data during multiplayer.