Connecting Computer to Rednet Cable

Im trying to set up my computer via red net cable or wireless modem to send a signal to my pistons to open/close on a command from my computer

What would i have to type in to set up this command???

Please help

1) What kind of rednet cable? The networking cables from CC, the MFR cables, or …?

2) What version of CC are you using?

3) Here in AaP, we tend to avoid writing code for you and prefer you learn yourself. Take a look at "help redstone" and "help rednet" from the shell.