FAQ: Client Access Licenses (CAL)
Find answers to questions from our customers related to CALs.
Table of contents
What is a Client Access License (CAL)?
A Client Access License (CAL) is a document confirming access rights, which is required during a software audit as proof that a server product is properly licensed in terms of the number of users and devices that have been granted access. It is not a software product of any sort, so it does not need to be installed or deployed in any way.
There is one exception to this rule – RDS CALs.
What types of CALs are there?
There are two main types of CALs and CAL Suites:
User CAL – one user has access to the server and its services from an unlimited amount of devices. User CAL is a great choice if your employee wants to access the server from multiple devices.
Device CAL – one device has access to the server and its services and can be used by an unlimited number of users. Device CAL is a better choice if your employees share one device, for example on different work shifts.
User CAL and Device CAL can be mixed and used all together within one server structure. This option allows users to purchase a suitable amount of each type of CAL, depending on what fits the company server infrastructure best.
Additionally, you only need one CAL per user/device per server product regardless of the number of servers.
Example: One Windows Server 2019 User CAL grants access to all Windows Server 2019 servers within a company or organization.
What is an RDS CAL?
An RDS CAL (Remote Desktop Services Client Access License) is a required license for users or devices which grants access to remote desktops, applications, and files hosted on a given Windows Server via Remote Desktop Services (RDS).
Unlike all other CALs, RDS CALs do have a software component – they need to be set up in order for users or devicers to connect to Windows Server’s RDS. See how to set up RDS on your Windows Server in our guide.
What type of RDS CAL do I need – User or Device?
You need to select the appropriate Remote Desktop Service (RDS) Client Access Licenses (CALs) based on your network setup:
Domain → Windows Server RDS User CALs
Workgroup → Windows Server RDS Device CALs
What is a CAL Suite?
A CAL Suite is a document confirming access rights for server products, but unlike a singular CAL which gives access rights to only one specific server product (e.g. a Windows Server 2019 User CAL only gives access to Windows Server 2019), a CAL Suite grants access to many server products and services at once (e.g. a Core CAL Suite 2019 User CAL gives access to Windows Server 2019, Exchange Server 2019, SharePoint Server 2019 and more).
In summary, CAL Suites are an indivisible* package of CALs that allow access to a variety of server products and services, which depend on the CAL Suite edition – Core or Enterprise.
*One CAL Suite can be assigned to just one user or one device – it cannot be split up among multiple users and devices.
What does a Core/Enterprise CAL Suite contain?
Core CAL Suite: Windows Server CAL, Exchange Server Standard CAL, SharePoint Server Standard CAL, Skype for Business Standard CAL, Skype for Business Server Standard CAL, Microsoft Endpoint Configuration Manager Client ML, System Center Endpoint Protection Client ML.
Enterprise CAL Suite: all components of the Core CAL Suite listed above, plus: Exchange Server Enterprise CAL, SharePoint Server Enterprise CAL, Skype for Business Server Enterprise CAL, Windows Server Active Directory Rights Management Services CAL, Advanced Threat Analytics Client ML, Microsoft Audit and Control Management Server CAL.
Do CAL Suites include an SQL CAL?
No, SQL CALs have to be purchased separately.
How many users or devices can one CAL Suite be used by?
One CAL Suite covers one user or one device.
How many servers can be accessed with a CAL Suite?
A CAL Suite covers a specified number of users or devices and provides access rights to any server within your organization.
Are CAL Suites compatible with older server versions?
Yes, CAL Suites can be used for accessing servers with the same year of release or any of the older server versions.
How do downgrade rights apply to CALs?
Downgrade is an end-user right to revert a software to an older version, offered by Microsoft for products purchased via their Volume distribution channel. Downgrade rights can also be applied to CALs and CAL Suites – for example, if you have an Exchange Server 2016 Standard, you can purchase an Exchange Server 2019 Standard User CAL and downgrade it to Exchange Server 2016 Standard User CAL. Unlike other products from the Volume channel, CALs and CAL Suites are fully backwards compatible – the latest CAL release can be used to allow access even to the oldest server versions.
Downgrade rights allow using an older version of a given product, but do not grant the right to change the edition or type of said product – e.g. Exchange Server 2019 Standard User CAL can become Exchange Server 2016 Standard User CAL, but it cannot become Exchange Server 2016 Enterprise User CAL.
Note: A Volume product with downgrade rights can be used in only one specific version at a given moment. This is valid for software products as well as all types of CALs.