1. The document discusses various options for deploying Skype for Business voice solutions, including on-premises, cloud-only, and hybrid models.
2. An on-premises deployment involves hosting all infrastructure and services locally, while a cloud-only model relies entirely on Office 365 hosted services including Cloud PBX and PSTN calling.
3. A hybrid model combines an existing on-premises Skype for Business deployment with cloud services, allowing users to be homed locally or online while sharing the same phone system resources.