What does RDP stand for?
RDP stands for Remote Desktop Protocol. Microsoft's protocol for a remote graphical session on a Windows machine, on TCP port 3389. Never expose it directly to the internet: use a VPN or gateway, enable Network Level Authentication and restrict which accounts can connect.
RDP is Microsoft's protocol for working on a remote Windows computer as if sitting in front of it: the screen is sent to the client, and the keyboard and mouse are sent back. It listens on port 3389. Network Level Authentication makes the user sign in before a full session is created. RDP that is reachable directly from the internet is one of the most attacked services there is, so remote access should go through a VPN or a Remote Desktop gateway, with multifactor authentication.
RDP in practice: an example
A technician needs to fix an application on a server in another building. She opens Remote Desktop Connection, enters the server name, signs in with her administrator account and sees the server's desktop in a window. From home, she first connects to the company VPN, because the firewall does not allow port 3389 from the internet.
What RDP is confused with
RDP vs VNC: what is the difference?
RDP is a Microsoft protocol that creates a Windows session for the remote user. VNC works on many platforms and shares the screen that is already displayed, which is why it is common for helping a user who is watching. What VNC stands for
RDP vs SSH: what is the difference?
RDP gives a graphical desktop, on port 3389. SSH gives an encrypted command line, on port 22. What SSH stands for
Which exams cover RDP?
RDP is on the official CompTIA acronym list for two of the four exams covered here.
- Network+ N10-009: 1.0 (Networking Concepts).
- A+ 220-1201 and 220-1202: 220-1201 2.0 (Networking); 220-1202 1.0 (Operating Systems); 220-1202 4.0 (Operational Procedures).
Each number is a CompTIA exam objective and the name in brackets is its domain. The exam puts the term in a scenario; it does not ask you to recite the expansion.
Check yourself: two practice questions
Written by CertSprint for this page. They are not taken from any exam.
1. Which port must be allowed through an internal firewall for Remote Desktop connections to a Windows server?
- 22
- 443
- 3389
- 5900
Show the answer
C. 3389. RDP uses port 3389 by default. Port 22 is SSH, 443 is HTTPS and 5900 is VNC.
2. A company finds that its server's RDP port is open to the whole internet and under constant password guessing. What is the best correction?
- Change the wallpaper on the server
- Close the port to the internet and require a VPN or gateway with multifactor authentication
- Give every user the same strong password
- Disable the server's event log
Show the answer
B. Close the port to the internet and require a VPN or gateway with multifactor authentication. Removing direct exposure stops the guessing at the source, and a second factor protects the accounts that connect through the approved path.
Sources: Microsoft Learn: Understanding the Remote Desktop Protocol (RDP); NIST glossary: Remote Desktop Protocol. The acronym and its expansion come from CompTIA's official acronym lists, linked from each exam glossary above. The explanation, example and questions are CertSprint's own, checked against these sources on 11 November 2026.