TCP vs UDP: Key Difference between TCP and UDP Protocol

TCP/IP is a protocol that helps you determine how a specific computer should be connected to the internet and how data can be transmitted between computers. When multiple computer networks are linked together, it can assist you in creating a virtual network.

TCP/IP is an abbreviation for Transmission Control Protocol/Internet Protocol, respectively. A model for providing a highly reliable and end-to-end byte stream over unreliable internetwork has been developed specifically for this purpose.

In this tutorial on the differences between TCP and UDP, you will learn:

What is UDP?

UDP is a datagram-oriented protocol that is used for the transmission of datagrams. It is used for network transmissions of the broadcast and multicast types, among other things. User Datagram Protocol (UDP) is the full name of this protocol (A datagram is a transfer unit associated with a packet-switched network.) The UDP protocol is very similar to the TCP protocol in that it eliminates all of the error-checking functionality, as well as all of the back-and-forth communication and deliverability.


In contrast to UDP, which is a connectionless protocol, TCP is a connection-oriented protocol.

TCP has a slower transfer rate, whereas UDP has a faster transfer rate.

TCP employs handshake protocols such as SYN, SYN-ACK, and ACK, whereas UDP does not employ any handshake protocols.

On the one hand, TCP checks for errors and recovers from them; on the other hand, UDP checks for errors but discards any packets that are found to be incorrect.

The acknowledgment segments of TCP are present, whereas the acknowledgment segments of UDP are absent.

When comparing the TCP and UDP protocols, we can see that TCP is more heavy-weight and UDP is more lightweight.

How does TCP work?

A three-way handshake is used to establish a TCP connection between two computers. Initiating and acknowledging a connection is the process by which a connection is established. Once the connection has been established, data transfer can begin, and once the transmission process has been completed, the connection is terminated by closing the virtual circuit that has already been established.

How does UDP work?

UDP is a straightforward transmission method that does not rely on implied hand-shaking dialogues to ensure order, reliability, or data integrity. UDP also assumes that error checking and correction are not important or are performed in the application, to avoid the overhead of such processing at the network interface level, as described above. Also compatible with packet broadcasts and multicasting are packet broadcasts and multicasting.

TCP has several characteristics.

The following are some of the most important characteristics of TCP:

Features of TCP

  • Acknowledgments of receipt of goods
  • Transmission is being discussed.
  • When the network is overloaded, it causes the transmission to be delayed.
  • Detection of errors is simple.
  • The following are some of the most significant characteristics of UDP:
  • Designed to support bandwidth-intensive applications that can withstand packet loss.
  • There will be a less waiting time.
  • It sends a large number of packets in a single batch.
  • There is a possibility of data loss.
  • Allows for small transaction sizes ( DNS lookup)
  • What is the difference between TCP and UDP?

Difference between TCP and UDP

Here are the main differences between UDP vs TCP:



Difference between UDP and TCP

Difference between UDP and TCP




It is a connection-oriented protocol. It is a connectionless protocol.
TCP reads data as streams of bytes, and the message is transmitted to segment boundaries. UDP messages contain packets that were sent one by one. It also checks for integrity at the arrival time.
TCP messages make their way across the internet from one computer to another. It is not connection-based, so one program can send lots of packets to another.
TCP rearranges data packets in a specific order. UDP protocol has no fixed order because all packets are independent of each other.
The speed for TCP is slower. UDP is faster as error recovery is not attempted.
The header size is 20 bytes The header size is 8 bytes.
TCP is heavy-weight. TCP needs three packets to set up a socket connection before any user data can be sent. UDP is lightweight. There are no tracking connections, ordering of messages, etc.
TCP does error checking and also makes error recovery. UDP performs error checking, but it discards erroneous packets.
Acknowledgment segments No Acknowledgment segments
Using handshake protocols like SYN, SYN-ACK, ACK No handshake (so connectionless protocol)
TCP is reliable as it guarantees the delivery of data to the destination router. The delivery of data to the destination can’t be guaranteed in UDP.
TCP offers extensive error checking mechanisms because it provides flow control and acknowledgment of data. UDP has just a single error checking mechanism that is used for checksums.

Applications of TCP

A lot of time-sensitive applications, as well as servers that answer small queries from a large number of clients, make use of the UDP communication method.

UDP is compatible with packet broadcasts for sending data throughout the network as well as for multicasting data.

The Domain Name System (DNS), Voice over IP (VoIP), and online games are all examples of applications where it is used.

TCP has several advantages.

The following are some of the advantages and disadvantages of TCP:

Advantages of TCP

It assists you in establishing or setting up a connection between different types of computers (see Figure 1).

It is independent of the operating system and can be used without it.

It is compatible with a large number of routing protocols.

It makes it possible for organizations to collaborate over the internet.

The TCP/IP model is characterized by a client-server architecture that is highly scalable.

It has the capability of being operated independently.

Supports several different routing protocols.

If you want to connect two computers, you can use this program.

UDP has several advantages.

The following are some of the advantages and disadvantages of UDP:

Advantages of UDP

Unlike other communication models, it does not impose any restrictions on you; this is why startup latency in distributed applications is extremely low.

The recipient of UDP packets receives them unmanaged, which includes block boundaries as well as the rest of the packet.

UDP can also be used for broadcast and multicast transmissions, among other things.

It is possible to suffer data loss.

Transaction of limited scope ( DNS lookup)

The app that consumes a lot of bandwidth and suffers from packet loss

TCP has several disadvantages.

The following are some of the drawbacks of using TCP:

Disadvantages of TCP

TCP never ends a transmission unless and until all data in motion is explicitly requested to do so.

You are not permitted to use this for broadcast or multicast transmission.

Because TCP does not have any built-in block boundaries, you must create your own.

TCP comes with a slew of features that you don’t need. It has the potential to waste bandwidth, time, or effort.

In this model, the transport layer does not ensure that packets are delivered to their destinations.

It is difficult to replace a protocol in TCP/IP.

A clear separation between the services, interfaces, and protocols isn’t provided by the system.

UDP has several disadvantages.

The following are some of the disadvantages and drawbacks of UDP:

Disadvantages of UDP

In the UDP protocol, a packet may not be delivered more than once or may not be delivered at all. It is possible that it will be delivered out of order, and you will not be notified.

Routers are extremely careless when it comes to UDP, and they never retransmit it if two packets collide.

Because UDP lacks Congestion Control and flows control, it is the responsibility of the user application to implement them.

UDP is the protocol that suffers the most from packet loss.

When should UDP and TCP be used?

Now, let’s look at the differences between the TCP and UDP protocols:

When to use UDP and TCP?

TCP is an excellent choice, even though it has associated overhead. As a result, when the majority of the overhead is in the connection, your application can remain connected for an extended period.

UDP is particularly well suited for use with multimedia, such as VoIP.

When both the client and the server independently send packets at the same time, TCP sockets should be used; an occasional delay is acceptable. (For example, Online Poker).

If both the client and the server are capable of sending packets independently, and if an occasional delay is not acceptable, you should use user UDP. (For example, multiplayer video games.)