Rednet Example

--remote terminal program
while true do
    term.clear()
    term.setCursorPos(1,1)
    write("Enter Password: ")
    sPassword = tostring(read())
    if sPassword == "Open Sesame" then
        rednet.send ( nDoorId, "safe to open" ) --nDoorId is the ID # of the door's computer
    end
end




--door program
while true do
    ID, message = rednet.receive ( 5 )
    if ID == safeID and message == "safe to open" then --safeID being the remote terminal's ID #
        --do door opening code
    else
        os.sleep(0.5)
    end
end