Client access licenses - Cals

When purchasing Windows Server, you also need to account for Client Access Licenses (CALs) and, in some cases, Remote Desktop Services (RDS) CALs. These licenses are required depending on how users or devices will access and interact with the server.

Client Access Licenses (CALs) for Windows Server are required to grant users or devices the right to access and use the server’s services. These CALs are necessary in addition to the server’s core license.

Types of Windows Server CALs:

• User CALs: A User CAL provides a license for a specific user to access the server from any device. This is ideal for employees who use multiple devices (e.g., desktops, laptops, mobile phones) to connect to the server.
• Device CALs: A Device CAL is tied to a specific device (e.g., a workstation, laptop, or kiosk). This option is useful when multiple users share the same device to access the server.

Key Points about Windows Server CALs:

• Required for Each User/Device: Each user or device accessing the server needs a CAL.
• No CALs for Internal Access: Even if the server is only used for internal purposes (such as file sharing or databases), CALs are still required for every user or device accessing it.
• External Connector License: External users (outside your organization) who need access to the server may need an External Connector License instead of individual CALs.

Remote Desktop Services (RDS) allow users to remotely access a Windows Server through a graphical desktop or virtual desktop infrastructure (VDI). RDS CALs are separate from regular Windows Server CALs and are required for users or devices that need remote access to the server, including hosted applications.

Types of RDS CALs:

• User RDS CALs: A User RDS CAL grants a specific user the right to access the server remotely from any device. This is useful for users who need to access the server from various locations or devices (e.g., from home, a mobile device, or while traveling).
• Device RDS CALs: A Device RDS CAL grants a specific device the right to access the server remotely. This is helpful if multiple users access the server remotely using the same device (e.g., in a shared workstation environment).

Key Points about RDS CALs:

• Separate from Windows Server CALs: RDS CALs are required in addition to Windows Server CALs when remote desktop access is needed.
• Access to Remote Desktops or Apps: RDS CALs provide access to remote desktops and applications hosted on the server.
• Required for Remote Access: If users will be using RDS features (such as virtual desktops or remote applications), they must have an RDS CAL.

When Do You Need Both Windows Server CALs and RDS CALs?

• If users are accessing the server locally (e.g., through file shares or applications installed on the server), they only need Windows Server CALs.

• If users are accessing the server remotely using Remote Desktop Services (RDS), they will need both:

  • Windows Server CALs (for general access to the server),
  • RDS CALs (for remote desktop or application access).

  You can choose between User RDS CALs (for users accessing from any device) or Device RDS CALs (for shared devices accessed by multiple users remotely).

Summary

• Windows Server CALs are necessary to access the server itself.
• RDS CALs are required for remote access to Windows Server through Remote Desktop Services.
• Both User CALs and Device CALs are available for each license type, depending on how access is managed.
• RDS CALs are essential if users or devices require remote desktop or remote application access, in addition to the standard Windows Server CALs.

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