You are an IT administrator responsible for managing a medium$-$sized business network that has experienced significant growth in the number of connected devices. The current network infrastructure relies on IPv$4,$ and you are tasked with addressing the challenges posed by address exhaustion. You have a need for future scalability and must consider the challenges outlined in this exploration. In light of the challenges posed by address exhaustion in your medium$-$sized business network using IPv$4,$ what would be the most suitable solution to ensure future scalability and seamless communication?