A cloud-hosted unified communications solution requires little on-site infrastructure beyond broadband internet (which many businesses already have on hand) and internet-connected devices like smartphones, tablets, and laptops. An on-premises UC solution does require more of an investment, including on-site servers and other equipment. (Note that, for companies struggling to migrate from on-premises to the cloud, there are solutions that can smooth the transition; for example, SIP trunking allows a business to run a legacy PBX phone system over the internet without needing to completely replace all existing hardware or connection points.)