Exchange Server 2010 Standard 20 User CALs through Microsoft Open Business Licensing
This product comes pre-bundled with 20 CALs. If you need additional CALs you may order them seperately.
The Standard CAL is designed to help users be more productive from virtually any platform browser or mobile device with new features in Exchange Server 2010 that help manage communications overload and lower helpdesk costs. The Standard CAL works with either server edition.
A User CAL permits one user (using any device) to access or use Exchange server software. User CALs are likely to be more cost effective than Device CALs if there are multiple devices per user (for example a user has a laptop and handheld computer accessing Windows Server). This product comes pre-bundled with 20 CALs. You can order additional CALs if needed.