TCP vs UDP: Difference You Should Know

You may have heard of technical terms TCP and UDP while setting up a router, configuring your firewall software, or looking through VPN features, or you might have never heard of them. But what are TCP and UDP, and how are they different from each other?

To understand the difference between the two, you need to first know what they are. Here in this post, we have discussed everything in detail. So let us get started.

What is TCP?

TCP/IP or Transmission Control Protocol/ Internet Protocol helps determine how a computer should be connected to the internet and how you can transfer data between them. It allows you to create a virtual network when multiple computer networks are connected.

The TCP/IP is specially designed as a model to offer reliable and end-to-end byte stream over an unreliable network.

What is UDP?

UDP or User Datagram Protocol is a datagram-oriented protocol used for broadcasting and multicasting types of network transmission. The UDP protocol works similar to the TCP/IP, but it throws all the error-checking out, all the back and forth communication, and data delivery.

How does TCP Work?

A TCP connection is a 3-way transmission process. It is a process of initiating and acknowledging a connection. Once a connection is made, the data transfer begins, and once the transfer is finished, the connection is terminated by closing the virtual circuit.

How does UDP Work?

Unlike TCP/IP, UDP uses a simple transmission method for ordering, reliability, and data integrity. According to the UDP protocol, error checking and correction is not important in the application.

This helps to avoid the overhead of processing at the network interface level. UDP is also compatible with packet broadcasts and multicasting.

Features of TCP/IP

1. Acknowledgment of all the deliveries.
2. Re-transmission.
3. Delay the transmission if there is any network error.
4. Easy error detection.

Features of UDP

1. Supports bandwidth-intensive applications that can tolerate packet loss.
2. Less delay in transmission.
3. Can share bulk quantities of data.
4. Possibility of data loss.
5. Also allows the transmission of fewer data.

Advantages of TCP

• TCP/IP is an industry-standard model that is used in practical networking problems.
• It allows communication with different platforms among heterogeneous networks.
• TCP/IP is an open protocol suite and thus, can be used by any individual or organization.
• It is scalable and has a client-server framework. It allows different networks to be added without disturbing the current service.
• The TCP protocol assigns an IP address to every computer on the network, making each device identifiable over the network. It assigns each site a domain name and also offers name and address resolution services.
• TCP/IP model is highly scalable and is the best client-server framework.

Disadvantages of TCP

• It is not generic. Therefore it fails to represent any protocol stack other than the TCP/IP network.
• TCP does not separate the services interfaces and protocols. Therefore it is not a suitable protocol to describe new technologies in the network.
• It cannot differentiate between the data link and the physical layers that have different functions.
• The protocol is designed and used for wide area networks and is not optimized for small networks, like LAN and PAN.

Advantages of UDP

1. It never restricts you from using the connection-based communication framework.
2. The recipient of UDP data gets them unmanaged, including the block boundaries.
3. UDP makes broadcast and multicast transmission easy.
4. It allows small transactions.

Disadvantages of UDP

• In the UDP protocol, the data files may not be delivered or delivered twice and do not show any alert.
• Routers are careless in the case of UDP, so they never retransmit when they collide with each other.
• UDP has no congestion and flow control, so the user application is responsible for the implementation.
• There is a lot of data loss that occurs during the file transfer in UDP.

Difference Between TCP and UDP (TCP vs UDP)

Now that you know the definition, features, advantages, and disadvantages of TCP and UDP. Here in this section, we have mentioned the difference between the two. So let us get started:

TCP/IP	UDP
It is a connection-oriented protocol.	It is a connectionless protocol.
TCP reads data as bytes, and the data is transmitted to segment boundaries.	UDP messages contain data files that are sent one by one. It also allows you to check the integrity of data at the arrival time.
TCP messages establish a connection from one computer to another.	Since it is not connection-based, one program can send many data packets.
TCP rearranges data packets in a specific order.	Since all the data packets are independent, the UDP protocol follows no fixed order.
TCP is very slow.	UDP is faster, and no error can occur.
The header size is 20 bytes.	The header size is 8 bytes.
TCP is heavy. It needs 3 data packets to create a connection and transfer data from one network to another.	Since UDP is lightweight, it does not track any network connection.
TCP checks and detects, and solves all the errors.	UDP checks for errors but discards error packets.
It uses handshake protocols, like SYN, SYN-ACK, and ACK.	It does not use the handshake protocol.
Acknowledgment segments.	Non-acknowledgment segments.

When to use TCP and UDP?

• TCP is the best choice and has associated overheads. So most of the overheads in your application stay connected for a very long time.
• UDP is the best with different multimedia like VoIP.
• You should use TCP sockets when both the client and the server send data packets at that time. Plus, there will be occasional delays.
• You should use UDP if both clients and servers send data packets separately and there is no delay.

Final Thoughts!

Here in this post, we mentioned the difference between TCP and UDP. Let us recap:

• TCP is Transmission Control Protocol, and UDP is known as User Datagram Protocol.
• TCP is a connection protocol, and UDP is a connectionless protocol.
• TCP messages establish a connection from one computer to another. On the other hand, UDP is one program that sends many data packets.
• TCP/IP is very slow, and occasional errors occur. UDP is fast and comes with zero errors.
• TCP is bulky. It needs three data packets to create a connection and transfer data from one network to another. On the other hand, UDP is lightweight and does not track any network connection.