Unified Communications-as-a-Service (North America):

Unified Communications as a Service (UCaaS) is a category of “as a Service” or “Cloud” delivery mechanisms for Enterprise Communications. Similar to “Platform as a Service” (PaaS) (where data center capacity is made available to an enterprise on a consumption model from a service provider), with UCaaS, unified communications services can be made available from the cloud to enterprises. UCaaS is part of the global industry trend towards cloud services.