A Grandstream is a small device that connects your phone to your router. All you need to do is plug a supplied ethernet cable into the ethernet port on your Grandstream device and plug the other end of the cable into the top ethernet port on your Linksys router. Then you can connect the phone adaptor into the phone port on the Grandstream device and connect your phone.
If you need any help with installation please view our step-by-step guide.