Microsoft Remote Desktop Services (RDS) is a Windows Server feature that allows users to access desktops and applications remotely over a network. Instead of installing and managing everything on each endpoint, businesses can centralize desktops and apps in the data center or the cloud. They are able to give users access from almost anywhere. Microsoft’s current RDS guidance covers Windows Server 2025, making it the most relevant version for businesses.
What is RDS?
Remote Desktop Services, previously known as Terminal Services, is a role-based infrastructure in Windows Server that allows authorized users to connect to a full desktop or to specific applications known as RemoteApp programs. Microsoft positions RDS as a way to centralize application and desktop management, improve security, and give users a consistent experience whether they work from another location. RDS supports both multi session server-based desktops and single session virtual desktops, so organizations can choose the model that best fits performance, compatibility, and budget requirements.
It is useful to note that Microsoft and modern documentation refers to the workload host as RD Session Host, even though the older abbreviation RDSH is still commonly used in the current market.
For many organizations, RDS offers three major advantages:
- Centralized delivery of Windows desktops and applications
- Easier management and patching
- Secure remote access over the internet with RD Gateway,
Components of Remote Desktop Services
A full RDS environment can include several Windows Server roles that work together.
RD Session Host is the server role that hosts the actual Windows sessions and applications users work with. This is the core workload role in most RDS environments. In addition to this role, Microsoft documents several key infrastructure roles:
- RD Connection Broker to manage and broker user sessions
- RD Gateway to provide secure, encrypted access over the internet
- RD Licensing to install and manage RDS CALs
- RD Web Access to publish desktops and applications through a web portal
Microsoft also supports access to RDS resources from a range of client platforms, and according to their current guidance, users can connect through Windows App or the Remote Desktop client, depending on platform and scenario. Furthermore, Microsoft continues to support browser-based access through the Remote Desktop web client, which works in modern desktop browsers on Windows, macOS, ChromeOS, and Linux.
How RDS works in modern environments
RDS remains relevant for organizations that want to deliver Windows applications and desktops from a centralized environment while keeping data in the data center or in cloud infrastructure. Microsoft’s current architecture guidance shows that RDS can be deployed on premises, in Azure, in other cloud environments, or in hybrid scenarios. Both basic deployments and high availability deployments are documented, depending on business needs for scale and uptime.
For external access, RD Gateway plays an important role as it enables secure and encrypted connections to RDS resources over the internet. It also allows users to access internal resources remotely without the need for a VPN. That makes it especially relevant for businesses that want a controlled remote access setup without exposing internal systems directly.
Users are strongly advised to use Microsoft’s current platform guidance. According to it, using the most recent version of Windows Server for the Remote Desktop infrastructure is the norm. Additionally, the guidance notes that if you upgrade RD Session Hosts to Windows Server 2025, you should also upgrade the license server so it can process the appropriate CAL version.
RDS 2025 CALs: the current licensing version
If you are deploying or upgrading a modern environment, the current version to reference is Windows Server 2025 Remote Desktop Services CALs, often called RDS 2025 CALs. Microsoft’s own licensing documentation applies to Windows Server 2025, and Microsoft Store currently lists Windows Server 2025 Remote Desktop Services CALs in both User CAL and Device CAL options.
Each user or device that connects to a Remote Desktop Services session host running Windows Server needs an RDS CAL. These are additional to the underlying Windows Server access licensing requirements, so businesses should always review the full licensing picture before purchasing.
Read more about License Remote Desktop Services with Client Access Licenses (CALs).
RDS User CAL licensing model
User CALs are usually the best fit when one employee needs access from multiple devices, such as a desktop, laptop, tablet, or phone. In Microsoft’s licensing model, an RDS User CAL allows one licensed user to connect from any number of devices. That often makes this model attractive for office staff, hybrid workers, and employees who regularly switch between managed and unmanaged devices.
There is one important compliance point here: Microsoft states that per user licensing is not technically enforced in the same way as per device licensing. That means administrators remain responsible for making sure every user who connects is correctly licensed.
RDS Device CAL licensing model
Device CALs are often the better option when multiple employees share the same workstation or terminal. Microsoft specifically highlights environments with two or more shifts of workers using the same computers as a common case for the per device model. This can make RDS Device CALs a practical choice for manufacturing, retail, healthcare, education labs, and other shared device scenarios.
Microsoft also notes that temporary per device CALs can be issued on first sign in and that permanent Device CALs are then renewed through the license server. In contrast to per user licensing, per device licensing is actively tracked by the license server.
Can you combine RDS User CALs and RDS Device CALs?
Yes, in practice organizations can have environments where both licensing approaches exist, but the key issue is not whether it is technically possible. The real issue is whether you can keep your licensing administration clear and audit ready. Microsoft’s licensing guidance stresses that every user or device connecting to the RDS environment must be properly licensed, so a mixed approach only works well when there is strong internal tracking and a clear policy for who is licensed under which model.
For that reason, many businesses prefer to standardize on either User CALs or Device CALs per environment or user group, because it is easier to manage and easier to defend during a licensing review. That is not a Microsoft rule in itself, but it is a sensible operational best practice based on how the licensing model works.
Read more about License Remote Desktop session hosts.
Which RDS CAL model is right for your business?
As a rule of thumb:
- Choose User CALs when one employee uses several devices
- Choose Device CALs when several employees share the same device
- Review your setup carefully if you are moving from older Windows Server versions to Windows Server 2025, because the license server must also support the newer CAL version
Read more about RDS 2022 (Device CAL and User CAL).
Questions about RDS licensing?
Choosing between User CALs and Device CALs is not only a technical decision. It also affects your organization’s costs, compliance, and long-term IT management. If you are planning a new Remote Desktop Services environment, upgrading to Windows Server 2025 with RDS 2025 CALs, or reviewing your current licensing setup, it is important to select the right licensing model.
At Softtrader, our specialists can help you determine the most suitable and cost-effective Microsoft licensing solution for your business.
Request your quotation today and receive tailored advice for your RDS project.
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FAQs
What is Microsoft Remote Desktop Services (RDS)?
Microsoft Remote Desktop Services (RDS) is a role in Windows Server that allows users to remotely access Windows desktops and applications hosted on a central server. Instead of installing software on every device, applications and desktops run on a server while users connect to them remotely through a secure network connection.
Read more about Microsoft Remote Desktop Services overview in Windows Server.
What is the difference between Remote Desktop and Remote Desktop Services?
Remote Desktop typically refers to connecting to a single computer remotely. Remote Desktop Services (RDS) is a server-based solution that allows multiple users to access desktops or applications simultaneously from a centralized Windows Server environment.
Learn more about Remote Desktop Services.
What are RDS CALs?
RDS CALs (Remote Desktop Services Client Access Licenses) are licenses required for every user or device that connects to a Remote Desktop Session Host server. In addition to a Windows Server CAL, organizations must purchase an RDS CAL for each user or device accessing the RDS environment.
Read more about License Remote Desktop Services with Client Access Licenses (CALs).
What are RDS 2025 CALs?
RDS 2025 CALs are the latest generation of Remote Desktop Services Client Access Licenses designed for Windows Server 2025 environments. These licenses allow users or devices to access Remote Desktop Services hosted on Windows Server 2025.
What is the difference between User CAL and Device CAL for RDS?
A User CAL allows one specific user to access Remote Desktop Services from multiple devices. A Device CAL allows a single device to access RDS, even if multiple users use that device. The best option depends on how employees access the system and how many devices are involved.
Read more about License Remote Desktop Services with Client Access Licenses (CALs).
When should you choose User CALs?
User CALs are typically the best option when employees work from multiple devices, such as a desktop, laptop, tablet, or smartphone. They are common in offices with hybrid work or remote employees.
When should you choose Device CALs?
Device CALs are often more cost effective when multiple employees share the same workstation, such as in factories, call centers, healthcare environments, or schools.
Can you mix User CALs and Device CALs in the same RDS environment?
Yes, organizations can use both licensing models in the same environment. However, it is important to keep clear records to ensure every user or device accessing the server is properly licensed according to Microsoft licensing rules.
Read more about License Remote Desktop session hosts.
Do you need a Windows Server CAL in addition to an RDS CAL?
Yes. Microsoft requires both a Windows Server CAL and an RDS CAL for each user or device that accesses Remote Desktop Services.
Read more about Desktop Application Software for use with Windows Server Remote Desktop Services licensing guidance.
Is Remote Desktop Services still used in modern IT environments?
Yes. Many organizations still use RDS to deliver centralized desktops and applications. It is commonly used in on premises infrastructure, hybrid cloud environments, and hosted data centers to provide secure remote access for employees.
How many users can connect to Remote Desktop Services?
The number of users that can connect to Remote Desktop Services depends on the server hardware, available resources, and number of RDS CALs installed. A single RD Session Host server can support many simultaneous sessions, but the exact number depends on CPU, RAM, and the workload of the applications being used.
Read more about Build and deploy your Remote Desktop Services deployment.
Is Microsoft RDS the same as Citrix?
No, Microsoft Remote Desktop Services and Citrix are not the same. RDS is a built-in Windows Server technology that enables remote desktop and application delivery. Citrix solutions often build on top of RDS infrastructure by adding advanced management tools, optimization features, and additional security capabilities.
Can RDS be deployed in the cloud?
Yes. Remote Desktop Services can be deployed on-premises, in public cloud infrastructure, or in hybrid environments. Microsoft documentation explains that organizations can run RDS workloads in their data center or in cloud platforms such as Azure while maintaining the same core architecture.
Read more about Plan and design Remote Desktop Services environment.
