Exchange Server Standard2016, 1 Device CAL Exchange requires a CAL for each user or device accessing the server software. There are two CAL variants here : StandardCAL: Enables every user to work productively across virtually any platform, browser and mobile device. Enterprise CAL: Provides additional functionality to help organizations reduce costs and meet compliance requirements, such as archiving and information protection capabilities or unified messaging integration. The Enterprise CAL is an add-on to the StandardCAL and extends it with specific functionalities. To activate the Enterprise CAL functions, a StandardCAL plus an Enterprise CAL must be licensed for each user. You can assign these access licenses either to a Device(Device CAL) or to a user (User CAL). Access licenses are version-specific, which means that the CAL version must be identical to or higher than the server version. Device CAL: A device CAL licenses a Devicefor use by a user to access instances of the ser...