The Microsoft Exchange Server Enterprise Client Access License (CAL) provides the necessary access for users to utilize the full potential of Microsoft Exchange Server. This license is designed for users who need advanced features and capabilities associated with the Enterprise edition of Exchange Server.
This license must be purchased in addition to the Exchange Server licenses. Each CAL grants access to a single user and includes software assurance for one year, ensuring that users stay up-to-date with the latest features and updates.
Microsoft PGI-00056?ANNIV2018 Exchange Server Cal - Enterprise