Hello

Need help. I have connected my decox60 yeasterday directly to fiberbox without router. The deco I have connected to act as router but when followed the steps of installation on the app on iPhone reaching the step when one is applying the SSID code found in the deco node but it did not ask for it in the app and connedted directly to the deco, then ask to give the wifi system a name and password. My question is : is it safe so if ot didnt ask for the ssid code? Can anyone connect to my wifi without a password? 
Thansk