Windows Server Cal

Windows Server Cal

The Windows Server CAL is a license that companies purchase in addition to the server licenses from Microsoft to allow individual users or devices to access the services of the Windows server. The abbreviation stands for "Client Access License" and is available as a User CAL for users and as a Device CAL for devices. As a company, using CALs allows you to meet legal requirements and ensure that your software is used properly. In a mixed environment, the latest version should always be used, while current RDS CALs (Remote Desktop Service) are useful for users who also need access from remote locations.

What are Windows Server CALs?

If you as a company want to expand your infrastructure, digitize new workplaces and expand the access options for your employees (clients) to the Windows server, Microsoft requires CAL licenses per user or device. At the same time, the licenses ensure that only authorized clients can access the server software and that you are on the safe side legally. The CAL licenses depend on the respective operating system. If you use a Windows Server 2019, you need a different license than for Windows Server 2022 and Windows Server 2025.

What Windows Server CALs are there?

A distinction is made between the User CAL license and the Device CAL license. Both each user and each device require an individual license to access Windows Server services. This applies not only to PC use, but also to mobile devices such as notebooks, smartphones or tablets. Individual end devices that are operated by several employees are also affected. In simple terms, this means that User CALs are necessary if there are more devices than users, and Device CALs if there are more users than devices.

User CAL license

You purchase the User CAL license for each individual user, who thereby receives exclusive access rights. It is useful if one person accesses the server from different devices, for example from a desktop PC in the office and from a laptop or smartphone on the go or at home.

Device CAL license

With a Device CAL, you license a specific device that can then be used by multiple users as required. This is useful if, for example, your company operates a call center or offers shift work, where occasional device access or the use of a device by multiple employees is necessary. Here you can track exactly which PC or mobile devices are active in the network.

RDS CAL license

There are also RDS CALs as an additional license for certain Windows features that allow access to the Remote Desktop Services. These are currently available as User CAL and Device CAL, primarily for administrators and for employees who need remote access, for example when working not only in the office but also from home. Accordingly, they are useful when access is made from different locations and from devices to the desktop and to applications that are hosted on the server.

Why do companies need CALs?

At Microsoft, CAL licenses are required for various Windows server services. This includes RDS CALs for access via the remote desktop, Exchange CALs for access to a mailbox and email traffic, and SQL Server CALs for access to the database system. You can decide which licenses are required for your company and adapt them individually to the access rights. In the terminal server environment, RDS access licenses must be activated. A CAL license is valid per device and per user, regardless of proxy, front-end, pooling and multiplexing solutions. Accordingly, it is not enough to license only individual intermediate parts of the chain, but always the device or the respective user at the end of the chain. If communication in your company takes place via a portal for employees, licensing is also necessary for each individual user. The same applies to devices such as the multifunction printer if it works via the server's network services. Administrative remote access rights also always require a license. As soon as a user accesses the desktop, RDS CALs must be configured and registered on the license server. This also applies to third-party solutions and all installed applications on the desktop Windows server.

When does the RDS CAL license make sense per user or per device?

With the current RDS CALs, you can choose between the User and Device CAL, with the products being offered for one user or one device, but also as a package for 5 and 10 users or devices. It is also possible to mix both license types. However, this is not always advisable, especially if employees use the same PC for access. If employees use their own dedicated Windows device to access RD session hosts, the User CAL per person is recommended. It is assigned via Active Directory, tracked by the server and cannot be revoked. However, tracking is not possible within a workgroup, so the Device CAL would be an alternative here, which also allows tracking regardless of Active Directory membership. A Device CAL, in turn, allows many users to access a device. The licenses for each device are physically assigned and are also available for 1, 5 or 10 devices. As soon as the second connection is established, the license server issues a permanent RDS CAL. For all variants, they must be entered on the license server and the Windows server must also be configured as an RDS license server in order to register the RDS CALs and ensure clean licensing. Tip: A mixture of User and Device CALs is particularly suitable for commercial companies that want to cover access in the office and in the field with User CALs and simplify production and assembly with Device CALs.

Windows Server CAL products

For “Windows Server 2025” there are RDS user CALs for 1, 5, 10, 25 and 50 users as Microsoft Windows Server 2025 RDS User CAL and RDS device CALs for 1, 5, 10, 25 to 50 devices in the version Microsoft Windows Server 2025 RDS Device CAL. You can select the number of CALs individually. For “Windows Server 2022” the client-based access license for 1 user is available as Microsoft Windows Server 2022 RDS - 1 User CAL or compact packages for 5 users or 10 users, here through the products Microsoft Windows Server 2022 RDS - 5 User CAL and Microsoft Windows Server 2022 RDS - 10 User CAL. Of course there is also the CAL license for 1 user. The "Windows Server 2019" requires licenses for 1 user or 1 device, including Microsoft Windows Server 2019 RDS - 1 User CAL and Microsoft Windows Server 2019 RDS - 1 Device CAL. There are also packages for 5 and 10 users or 5 and 10 devices, for users Microsoft Windows Server 2019 RDS - 5 User CAL and Microsoft Windows Server 2019 RDS - 10 User CAL and for devices Microsoft Windows Server 2019 RDS - 5 Device CAL and Microsoft Windows Server 2019 RDS - 10 Device CAL. All licenses are valid permanently. They are available in all languages ​​and are delivered within 24 hours.

The advantages of CAL licenses at a glance

• Compliance with legal requirements: To use Microsoft operating systems, every user or device that accesses the services of a Windows Server must have a valid CAL.
• Controlled access management: CALs allow companies to manage and control access to server services. You can decide whether you need user CALs or device CALs, depending on the specific needs of your business.
• Better cost efficiency: By choosing between user and device CALs, companies can adapt licensing to usage and field of work and thus save costs.
• High flexibility: Access to the server from different devices and users allows employees to switch between the office, home office and mobile devices.
• Support and updates: Owning CALs makes it easier to access support and software updates from Microsoft to ensure the highest level of security.
• Secure connection: Modern security features allow sensitive company data to be protected to protect the system from threats.