What is a CAL? Do I need a CAL?

As Microsoft explains, “A CAL is not a software product; rather, it is a license that gives a user the right to access the services of the server.”

The challenge with CAL licensing is that it requires a technical understanding of how devices and users are connecting to the embedded device. Each connection to a Windows Server or SQL Server requires a CAL, so the typical answer to the question, “Do I need a CAL for this scenario?” is most often, “Yes.”

There are two types of CALs: Device and User CALs. Figuring out the number of users and devices that will be connecting to the solution helps you determine which type to use. Our goal is cost effectiveness, so an OEM will want to select the lower number between the two.

User CALs

With User CALs, an OEM purchases a CAL for every user who accesses the server to use services, regardless of the number of devices they use for that access. This sort of license is useful for situations where users do not regularly have access to a specific machine, like a gas station company that monitors stations across a region, or when users tend to have access to their own personal machine, like in remote work.

Device CALs

When it comes to Device CALs, an OEM purchases a CAL for every device that has access to the server, rather than each specific user. In these cases, several users could utilize a single licensed device. This sort of license is useful for situations where multiple users might be accessing the same device, like a store open 24 hours a day, or a manufacturing facility where employees over several shifts use the same machine.

In general, User CALs are more common, however, there are certain scenarios that make Device CALs the better choice.

Choosing the right CAL

Here are a few interesting things to keep in mind on choosing the right CAL for your business. First, embedded program CALs are channel-agnostic, meaning if you purchase an embedded CAL, it can be used with products purchased in other Microsoft licensing channels (for example, Volume Licensing).

Second, you cannot use previous generation CALs with newer versions. For example, you may not use Windows Server 2016 CALs with Windows Server IoT 2019. Instead, you will need new 2019 version CALs. You can, however, use newer CALs with older products.

Finally, SQL Server CALs are typically more expensive than Windows Server CALs. But Microsoft has a Core-based SQL license available that provides for unlimited connections, meaning no CALs required. This often is a cost-effective choice for OEMs building solutions that require many (or difficult to predict) connections.