The two most common transmission protocols used to communicate over the Internet are:
TCP – Transmission Control Protocol and
UDP – User Datagram Protocol.
Both TCP and UDP are built on top of the Internet Protocol (IP), and both send bits of data, known as packets, to and from IP addresses. While both protocols do the same job, they go about it in very different ways. TCP is more concerned about accuracy. It allows devices to send and receive an ordered and error-checked stream of packets. UDP is more concerned with speed. It streams information faster by eliminating the error-checking.
TCP, UDP, and OpenVPN
OpenVPN, the VPN protocol that the Proton VPN Windows app and Linux command line tool are built upon, allows you to choose between TCP or UDP for your VPN connection. OpenVPN’s default is to use UDP simply because it is faster.
Our smart protocol selection feature will always attempt to establish a connection using UDP first. But you can also switch between UDP and TCP manually in our app or command line tool. However, unless there is a concrete reason to change protocols, Proton VPN recommends maintaining the default settings.
By default, OpenVPN uses UDP port 1194 and TCP port 443, but Proton VPN’s apps can connect via OpenVPN using multiple ports to defeat censorship attempts.
TCP, UDP, and WireGuard
By default, WireGuard uses UDP only. However, Proton VPN has adapted the protocol so that it can now run over TCP in our Android app (with support on more apps to follow). WireGuard TCP is more resistant to censorship than WireGuard UDP, but is not as effective as our custom Stealth protocol.
Learn how to how to change VPN protocols or select Smart Protocol
When to use UDP vs. TCP
- UDP does not use TCP’s error correction mechanism, which speeds up the connection and reduces latency. This is why we advise anyone streaming a video or playing a video game online use UDP.
- If you have not been able to connect using UDP or you are on an unstable network, we encourage you to switch to TCP and try to connect again. Because the Proton VPN app’s default port for TCP is 443, the port that handles HTTPS traffic, it is difficult to block. If a government official or network administrator were to implement such a block, they would make large portions of the Internet inaccessible. Furthermore, TCP traffic looks identical to traffic with HTTPS encryption, making it hard to detect.
- TCP may allow you to use your VPN even if you are in a country that blocks VPNs. (A government that uses deep-packet inspection will likely still be able to find and block your VPN, even if you use TCP.) It could also help you if you are on a controlled WiFi network, like at work or university. TCP is not as effective at defeating censorship as our Stealth protocol.
- If you are using the Proton VPN Windows app, the smart protocol selection feature will detect this block and switch to OpenVPN or WireGuard TCP automatically.
FAQs
UDP is faster, but TCP is more reliable and can be effective at defeating certain kinds of censorship (but not as effective as Stealth).
What is the difference between UDP and TCP in Proton VPN? ›
TCP is more concerned about accuracy. It allows devices to send and receive an ordered and error-checked stream of packets. UDP is more concerned with speed. It streams information faster by eliminating the error-checking.
Should I use UDP or TCP for VPN? ›
One is UDP (Port 1194), and the other is TCP (Port 443). Choosing the best protocol depends on a number of factors, but UDP typically offers the best performance for a VPN service and is the go-to choice except for some special circ*mstances.
Which protocol is best for Proton VPN? ›
Proton VPN performance with other protocols
| Protocol | Best use case |
|---|
| WireGuard | Best Proton VPN protocol overall |
| OpenVPN (TCP/UDP) | Best Proton VPN protocol for overall security |
| IKEv2/IPsec | Best Proton VPN protocol for Wi-Fi connection |
| Stealth | Best Proton VPN protocol for bypassing firewalls |
Apr 23, 2024
TCP is best used for direct communication in which a reliable connection is needed, such as web browsing, email, text messaging, and file transfers. UDP is best used for live and real-time data transmission when speed is more important than reliability.
Is it safe to use TCP or UDP? ›
TCP is more reliable and provides error-checking to ensure that data packets are delivered in the correct order. TCP is also slightly more secure than UDP because it tracks all data packets, making it more difficult to insert malicious data. Both TCP and UDP are supported by OpenVPN.
What type of VPN protocol is best? ›
OpenVPN is the most secure VPN protocol and the safest choice thanks to its near-unbreakable encryption, which keeps users' data private even when using public Wi-Fi. Because it's open source, users can check the source code for vulnerabilities and reassure themselves that there are no weaknesses in its security.
Why would you use UDP over TCP? ›
Typically, applications that transfer data files will use TCP since the protocol's latency and performance issues are not that critical. UDP benefits applications that need to receive data quickly even if accuracy suffers. This is why real-time applications like audio and video streaming will often use UDP.
Is TCP or UDP better for streaming? ›
User Datagram Protocol (UDP) is the superior choice for online streaming videos. UDP emphasizes speed and efficiency, making it exceptionally well-suited for real-time data transmission, including video streaming. It delivers data with minimal latency and without burdening your network's resources.
Is UDP or TCP better for private Internet access? ›
TCP is excellent for secure email, sensitive account access, and browsing because it offers stability and reliability. UDP is best for VOIP services, most streaming applications, and gaming because it's fast and efficient.
It provides a secure and reliable connection, advanced encryption protocols, a wide range of servers, a no-logs policy, and a user-friendly interface. However, it can be a bit slower, the free version has limited servers, no ad-blocker feature, a cluttered interface, and the relatively high cost of the paid version.
Which VPN is better than Proton? ›
NordVPN is better than ProtonVPN by a pretty wide margin. It has around 10 times as many servers in nearly 20 more countries, so it's likely that you'll get faster speeds with NordVPN compared to ProtonVPN. NordVPN also works with up to six devices, while ProtonVPN works with a maximum of five.
Does Proton VPN slow down internet? ›
All Proton VPN users, even those on our Free plan, have unlimited bandwidth and data. However, it is likely that your connection will be slightly slower when you are connected to one of our VPN servers than it is when you are browsing the Internet without using Proton VPN.
Should I use TCP or UDP for VPN? ›
SUMMARY: If your VPN gives you a choice out of UDP or TCP, try UDP first. UDP is faster than TCP, and you can still use TCP for activities such as web browsing inside your UDP VPN tunnel. Using TCP with your VPN can help if UDP is blocked by a firewall or you have an unreliable connection.
What are the disadvantages of UDP? ›
No reliability: UDP does not guarantee delivery of packets or order of delivery, which can lead to missing or duplicate data. No congestion control: UDP does not have congestion control, which means that it can send packets at a rate that can cause network congestion.
What are the benefits of using TCP instead of UDP? ›
TCP is more reliable (better) than UDP as it is guarantees the delivery of the data to the destination and provides an extensive error-checking system while UDP doesn't guarantee the delivery to the destination and provides only basic error-check system.
What is an advantage of UDP over TCP? ›
We learned that TCP is a connection-oriented protocol while UDP is a connectionless protocol. The main difference between TCP and UDP is their speed. UDP is a comparatively faster, simpler, and more efficient protocol. On the other hand, TCP is reliable and provides the advantage of retransmission of lost data packets.
What is the difference between TCP and UDP proxy? ›
The TCP and UDP transport protocols handle much of the data transferred over IP-based networks. TCP offers accurate delivery between two locations but requires more time and resources. UDP requires less overhead and lower latency but cannot guarantee that every datagram will be delivered.
What is the difference between UDP and TCP in Astrill VPN? ›
Speed is the major difference between TCP and UDP packets. UDP is faster than TCP because it permits a continuous packet stream. TCP permits a set of packets, transmitted by using the TCP window size and round-trip time (RTT).
Does DNS use TCP or UDP? ›
DNS has always been designed to use both UDP and TCP port 53 from the start 1 , with UDP being the default, and fall back to using TCP when it is unable to communicate on UDP, typically when the packet size is too large to push through in a single UDP packet.
