Differences between TCP and UDP

Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) both are protocols of the Transport Layer Protocols. TCP is a connection-oriented protocol whereas UDP is a part of the Internet Protocol suite, referred to as the UDP/IP suite. Unlike TCP, it is an unreliable and connectionless protocol. In this article, we will discuss the differences between TCP and UDP.

What is Transmission Control Protocol (TCP)?

TCP (Transmission Control Protocol) is one of the main protocols of the Internet protocol suite. It lies between the Application and Network Layers which are used in providing reliable delivery services. It is a connection-oriented protocol for communications that helps in the exchange of messages between different devices over a network. The Internet Protocol (IP), which establishes the technique for sending data packets between computers, works with TCP.

Grasping the differences between TCP and UDP is essential for excelling in exams like GATE, where networking is a significant topic. To strengthen your understanding and boost your exam preparation, consider enrolling in the GATE CS Self-Paced Course. This course offers comprehensive coverage of networking protocols, including in-depth explanations of TCP, UDP, and their applications, ensuring you’re well-prepared for your exams.

Transmission Control Protocol

Features of TCP

• TCP keeps track of the segments being transmitted or received by assigning numbers to every single one of them.
• Flow control limits the rate at which a sender transfers data. This is done to ensure reliable delivery.
• TCP implements an error control mechanism for reliable data transfer.
• TCP takes into account the level of congestion in the network.

Applications of TCP

• World Wide Web (WWW) : When you browse websites, TCP ensures reliable data transfer between your browser and web servers.
• Email : TCP is used for sending and receiving emails. Protocols like SMTP (Simple Mail Transfer Protocol) handle email delivery across servers.
• File Transfer Protocol (FTP) : FTP relies on TCP to transfer large files securely. Whether you’re uploading or downloading files, TCP ensures data integrity.
• Secure Shell (SSH) : SSH sessions, commonly used for remote administration, rely on TCP for encrypted communication between client and server.
• Streaming Media : Services like Netflix, YouTube, and Spotify use TCP to stream videos and music. It ensures smooth playback by managing data segments and retransmissions.

Advantages of TCP

• It is reliable for maintaining a connection between Sender and Receiver.
• It is responsible for sending data in a particular sequence.
• Its operations are not dependent on Operating System .
• It allows and supports many routing protocols.
• It can reduce the speed of data based on the speed of the receiver.

Disadvantages of TCP

• It is slower than UDP and it takes more bandwidth.
• Slower upon starting of transfer of a file.
• Not suitable for LAN and PAN Networks.
• It does not have a multicast or broadcast category.
• It does not load the whole page if a single data of the page is missing.

What is User Datagram Protocol (UDP)?

User Datagram Protocol (UDP) is a Transport Layer protocol. UDP is a part of the Internet Protocol suite, referred to as the UDP/IP suite. Unlike TCP, it is an unreliable and connectionless protocol. So, there is no need to establish a connection before data transfer. The UDP helps to establish low-latency and loss-tolerating connections establish over the network. The UDP enables process-to-process communication.

User Datagram Protocol

Features of UDP

• Used for simple request-response communication when the size of data is less and hence there is lesser concern about flow and error control.
• It is a suitable protocol for multicasting as UDP supports packet switching .
• UDP is used for some routing update protocols like RIP(Routing Information Protocol) .
• Normally used for real-time applications which can not tolerate uneven delays between sections of a received message.

Application of UDP

• Real-Time Multimedia Streaming : UDP is ideal for streaming audio and video content. Its low-latency nature ensures smooth playback, even if occasional data loss occurs.
• Online Gaming : Many online games rely on UDP for fast communication between players.
• DNS (Domain Name System) Queries : When your device looks up domain names (like converting “www.example.com” to an IP address), UDP handles these requests efficiently .
• Network Monitoring : Tools that monitor network performance often use UDP for lightweight, rapid data exchange.
• Multicasting : UDP supports packet switching, making it suitable for multicasting scenarios where data needs to be sent to multiple recipients simultaneously.
• Routing Update Protocols : Some routing protocols, like RIP (Routing Information Protocol), utilize UDP for exchanging routing information among routers.

Advantages of UDP

• It does not require any connection for sending or receiving data.
• Broadcast and Multicast are available in UDP.
• UDP can operate on a large range of networks.
• UDP has live and real-time data.
• UDP can deliver data if all the components of the data are not complete.

Disadvantages of UDP

• We can not have any way to acknowledge the successful transfer of data.
• UDP cannot have the mechanism to track the sequence of data.
• UDP is connectionless, and due to this, it is unreliable to transfer data.
• In case of a Collision, UDP packets are dropped by Routers in comparison to TCP.
• UDP can drop packets in case of detection of errors.

Which Protocol is Better: TCP or UDP?

The answer to this question is difficult because it totally depends on what work we are doing and what type of data is being delivered. UDP is better in the case of online gaming as it allows us to work lag-free. TCP is better if we are transferring data like photos, videos, etc. because it ensures that data must be correct has to be sent. In general, both TCP and UDP are useful in the context of the work assigned by us. Both have advantages upon the works we are performing, that’s why it is difficult to say, which one is better.

Difference Between TCP and UDP

Where TCP is Used?

• Sending Emails
• Transferring Files
• Web Browsing

Where UDP is Used?

• Gaming
• Video Streaming
• Online Video Chats

Differences between TCP and UDP

TCP is a connection-oriented protocol. Connection orientation means that the communicating devices should establish a connection before transmitting data and should close the connection after transmitting the data.

UDP is the Datagram-oriented protocol. This is because there is no overhead for opening a connection, maintaining a connection, or terminating a connection. UDP is efficient for broadcast and multicast types of network transmission.

TCP provides extensive error-checking mechanisms. It is because it provides flow control and acknowledgment of data.

Sequencing of data is a feature of Transmission Control Protocol (TCP). this means that packets arrive in order at the receiver.

Example: Suppose there are two houses, H1 and H2, and a letter has to be sent from H1 to H2. But there is a river in between those two houses. Now how can we send the letter?
Solution 1: Make a bridge over the river and then it can be delivered.
Solution 2: Get it delivered by a pigeon.

• Consider the first solution as TCP . A connection has to be made (bridge) to get the data (letter) delivered. The data is reliable because it will directly reach another end without loss of data or error.
• The second solution is UDP . No connection is required for sending the data. The process is fast as compared to TCP, where we need to set up a connection(bridge). But the data is not reliable: we don’t know whether the pigeon will go in the right direction, will drop the letter on the way, or some issue is encountered mid-travel.

Conclusion

To summarise, TCP and UDP are both important Transport Layer protocols with distinct properties and uses. TCP offers dependable, orderly, and error-free data transmission, making it ideal for operations that require precision, such as file transfers and web browsing. UDP, on the other hand, provides quicker, connectionless communication that is excellent for real-time applications such as gaming and video streaming, when speed is critical and minor data loss is acceptable. The exact requirements of the task at hand determine whether TCP or UDP should be used.

Frequently Asked Questions on TCP and UDP – FAQs

Which is faster: TCP or UDP?

UDP is faster than TCP. The reason for the faster UDP is its non-existent acknowledge packet (ACK) which allows the streaming of continuous packets where as TCP always works on the acknowledgment of a set of packets calculated with the help of TCP window size and Round Trip Time (RTT) .

Which is better for Video Conferencing?

Both Protocols, TCP and UDP have several practical uses in day-to-day life, but TCP has come as a better solution nowadays in the modern era as a solution for this question of who is better at Video Conferencing.