User Datagram Protocol (UDP): How to Use it in the right place, at the right time.

User Datagram Protocol (UDP): How to Use it in the right place, at the right time.

A Comprehensive Guide to Understanding UDP, When You Should Use It and it's performance benefits with examples written in NodeJS.

The Internet is a huge and ever-changing space. At any given time, it has several different streams of traffic moving through it, although they rarely all head in the same direction. As a result, depending on the type of information being transferred, various protocols are needed to help with data transfer in various directions. One such protocol is User Datagram Protocol (UDP) which operates differently from its counterpart, Transmission Control Protocol. Let's examine UDP's specifics, how it differs from TCP, and when it should be used to enhance network performance.

What is User Datagram Protocol (UDP)?

User datagram protocol (UDP), sometimes referred to as Universal datagram protocol, is an Internet protocol for data transmission without providing error checking or a guarantee of delivery. If the data is lost, there is no retransmission offered. Although it may not seem like the best way to handle data transfer, this approach has some benefits, especially when efficiency and speed are top objectives. UDP is in Layer 4, or transport, of the Open Systems Interconnection (OSI) Model.

Understanding the Differences Between UDP and TCP

TCP is typically used for larger data transfers that need verification that the recipient is ready to receive them. Before data is exchanged, this validation is made through a "handshake" or another procedure that confirms the well-being of both the sender and the recipient. Because of this, TCP is slower. TCP makes sure that both sides are prepared to accept the data and transfer it completely.

UDP characteristics include the following:

  • It is connectionless.
  • It is best for VoIP, video streaming, gaming and live broadcasts.
  • It allows for missing packets.
  • It uses fewer resources and is faster.
  • The packets don't always come in the correct order.
  • It is better suited for applications that need a fast, efficient transmission, such as games.

TCP characteristics include the following:

  • It is a connection-based protocol.
  • It ensures that all sent data reaches the intended receiver and that no packets go missing.
  • it delivers packets in the correct order.
  • It's slower and requires more resources.
  • It is best suited for apps that need high reliability, and transmission time is relatively less critical.

Example: How to create a UDP service

A UDP service can be written in any programming language. But in this section, we'll be working with NodeJS and Typescript. Working with Datagram sockets is made possible by the NodeJS dgram module. It can be used to transmit messages between computers or servers.

The server

import { createSocket, RemoteInfo } from "dgram"

// Creates a dgram.Socket object
const udpserver = createSocket("udp4")

// Registers a listener function to be called when a message is received.
udpserver.on("message", (message: Buffer, remote: RemoteInfo) => {
  console.log(`server got: ${message} from ${remote.address}:${remote.port}`)

// Binds the socket to a port and starts listening for datagrams on the socket
udpserver.bind(8273, "localhost")

Closing the connection

// Later, when you're ready to close the connection

The client

import { createSocket, RemoteInfo } from "dgram"

// Creates a dgram.Socket object
const udpserver = createSocket("udp4")

const data = "Message from UDP client";

// Creates a buffer from the string data
const message = Buffer.from(data);

// Sends the message to the server
udpclient.send(message, 8273, "localhost", (err) => {
  if (err) {
  console.log("message sent")
  udpclient.close(); // close socket

When Should You Use UDP?

As was already noted, UDP works well for brief data transfers that don't need to be confirmed before being delivered. In situations where efficiency and speed are high objectives, UDP is ideal. UDP sends the data without any verification to ensure that it is transferred quickly. Because data loss is a possibility with UDP, it is not recommended for massive data transfers where accuracy and integrity are more crucial. UDP is the best protocol to use for transferring data that can be completed in a single transmission.

Ideally, I would consider UDP for the following

  1. Game Development
  2. Broadcasting and Multicasting
  3. VoIP
  4. Simple Logger

Tips to Optimise Network Performance with UDP

Now that we've discussed when and why you might utilise UDP, let's look at some ways you might use UDP to improve the speed of your network.

  • Making ensuring that your network equipment is set up correctly to function on UDP should be your first priority. This also applies to the hardware you employ to link several network parts together, such as routers.
  • Make sure you are employing a reputable network monitoring provider. This guarantees that you are able to recognise and address problems as soon as they appear.
  • Be sure you are using a reliable network switch architecture. The network switch architecture determines your network's efficiency. Dependable network switch architecture improves UDP performance.

Limitations of User Datagram Protocol (UDP)

While there are many advantages to using UDP, it is important to understand its limitations as well.

  • Data loss is a genuine concern because UDP offers no delivery verification. This is not only a drawback, but it also raises security issues, especially when sending sensitive data.
  • Most networks prioritise TCP over UDP. This means that compared to TCP, UDP transmission is assigned a lesser priority and is less likely to be sent promptly.
  • UDP makes network monitoring more difficult because data isn't confirmed as received. You won't know whether there's a problem until the recipient contacts you.


Now that you’ve read this article, you should have a better understanding of what UDP is and how it differs from TCP. We’ve covered when and why you would use UDP, as well as tips to optimize your network performance with UDP. We’ve also discussed the limitations of UDP, so now you can make an informed decision on which protocol to use.