If you need to access a computer remotely, you have the option of using Remote Desktop Protocol (RDP) or Virtual Network Computing (VNC). Sometimes it may not be clear which option to use when. This article will compare these two technologies to clear up any confusions you may have and provide a general overview of the difference between VNC and RDP protocols.
VNC and RDP – What do they do?
RDP and VNC are both protocols that allow you to connect and access a device or computer remotely.
Using RDP or VNC you can:
- • Access the user interface of the remote computer and perform all actions as if you were sitting in front of the computer.
- • Allow technical support staff to troubleshoot by logging in to a remote computer and working on the problem at the source.
- • Connect two devices using a direct peer-to-peer connection.
To use RDP or VNC, you must install software on both the client and the server machines. The server is the machine that you wish to access remotely while the client is the device from which you will be accessing the server. An additional configuration requirement is that the software installed on the server must be set up to allow remote access.
RDP server software only works with the Windows operating system and is preinstalled on all Windows Server versions as well as Windows 10 Professional and above. However, RDP clients are available for most popular operating systems such as macOS, Linux as well as iOS, and Android.
Unlike RDP, VNC server software is compatible with all operating systems, and client software is easily available for download online.
What is RDP?
Remote Desktop Protocol or RDP is a proprietary protocol developed by Microsoft. It provides the opportunity to connect to a remote computer and take control of the desktop as if you were actually sitting in front of the remote computer.
RDP is defined as a semantic protocol – what this means is the data that is transferred between client and server happens at a level deeper than visuals. This makes data transfer fast and efficient. RDP allows for desktop sharing and resource sharing across remote computers.
What is VNC?
VNC stands for Virtual Networking Computing. It allows desktop sharing using remote frame buffer or RFB protocol. RFB allows access to all system settings and applications of the server machine. Remote access can be granted and someone at the server machine can view what is happening and interact with the remote user.
VNC offers greater flexibility than RDP, but it is less efficient – as it is pixel-based, it deals with the transmitting of raw data between server and client. The disadvantage of this is the reliance on bandwidth quality as lag can be evident when using a poor connection. This can also result in higher connectivity costs when compared to an object-based protocol. Some common VNC applications available include RealVNC, TeamViewer, TightVNC, and AnyDesk.
The differences between RDP and VNC protocols
It is not possible or correct to declare RDP to be better than VNC or vice versa. Each protocol has its specific use case, and it should be implemented accordingly.
1. The way VNC and RDP work
As a pixel-based desktop sharing system, VNC sends pixels across the network to the requesting client in what is essentially an image exchange. This process is slower than RDP but the upside to this is the ease of cross-platform sharing. RDP on the other hand is object-based, its basic function is to transmit the server monitor or display to the requesting client machine. The encrypted data is sent in blocks and results in a faster and more efficient process.
VNC is essentially a screen-sharing protocol and is ideal for collaboration sessions which include presentations and training, as well as remote technical support functions. Each logged-in client can view and interact within the same session. RDP on the other hand does not allow concurrent logins and a new login will automatically force a previous session to log off.
3. VNC vs RDP performance
The main goal of RDP is resource sharing, not screen sharing. For that reason, it provides a much faster and more efficient way of accessing a remote computer. RDP is often used in Virtual Private Servers (VPS) to allow multiple users simultaneous yet autonomous access to the same resources.
4. Supported operating systems
RDP may be a proprietary Microsoft application, but RDP clients can be run on all common operating systems including Windows, Mac, and Linux, as well as mobile operating systems iOS and Android. The limitation on RDP is that the Server software is only compatible with the Windows operating system.
VNC is platform agnostic and will run across all typical operating systems. The client software does not impose any restrictions on the operating system of the server machine allowing you to connect from any operating system or device.
5. VNC vs RDP security
RDP makes use of RSA Security’s RC4 cipher to encrypt data that is transferred between server and client. It is important to maintain your software updates to ensure you benefit from all new security updates. Older versions of RDP were known to be vulnerable to “man-in-the-middle” attacks. Secure RDP access is available with the help of SSL / TLS on most versions of Windows and Windows Server.
VNC makes use of end-to-end encryption and relies on passwords. It is possible to secure VNC further by using SSH tunneling. This is not a standard feature of VNC and entails further configuration that is not within the scope of this article. The downside of using an SSH tunnel is that the remote user gains full access to the server which could be a security risk.
Use cases comparison: VNC and Remote Desktop
Use RDP when you need:
- • to share resources from one computer to one or many other users remotely;
- • to access a computer without necessarily sharing the screen;
- • multi-screen support.
Choose VNC if:
- • the user on the server machine still requires access to the computer;
- • screen sharing is a necessity such as presentations or educational sessions;
- • cross-platform access is required.
RDP and VNC have very different specific use cases, and both offer a great solution for their specific purpose. RDP is more suitable for remote resource sharing while VNC is purpose-built for remote screen sharing.