TCP vs UDP: When to Use What, and How TCP Relates to HTTP

Think if millions of computers start communicating with each other without any rules, there will be chaos. That is why we need protocols like TCP and UDP to make communication effective and meaningful. In this article we will understand TCP and UDP transport protocols, when to use what, and how TCP relates to HTTP protocol.

TCP vs UDP

TCP (Transmission Control Protocol) is a transport protocol that transfers data from one computer to another reliably, ordered, and error-free. It ensures safety and reliability. Think of it like a courier, which takes the package, ensures everything is OK, and delivers it safely and reliably.

UDP (User Datagram Protocol) is also a transport protocol that does the same work of transferring the data from one computer to another, but the working of both protocols is different. UDP is fast but not reliable; it’s risky because it does not ensure that all data will be delivered, it does not retransmit the lost data, and it throws data and does not care whether the receiver will receive it or not. Think of it like an announcement; an announcement is made, and they don’t care whether anyone listens or not; they make it.

So the use cases of TCP and UDP are different TCP is used when accuracy matters more than speed, like loading a website, logging into a system, banking, etc. Think if a single chunk of data will be lost while making an online payment and you’ll transfer $1000 and the receiver will receive only $1. On the other side UDP is used when speed matters more than accuracy and precision, like in video calling, live streaming, etc.

How does TCP relate to HTTP?

HTTP works on top of TCP, TCP works in the transport layer, and HTTP works in the application layer. Both of the protocols work together to ensure effective communication with the server. HTTP defines what data is to be sent or fetched, and TCP sends the data or fetches it. Many think that these protocols are the same, but no, they are totally different and work together. And some may be thinking that if HTTP is used, then why use TCP? I already mentioned it. HTTP can’t work without TCP.

Conclusion

Both TCP and UDP are transport protocols that are used to transfer the data on a network. TCP ensures reliability, ordering of data packets, error-free delivery, etc., while UDP is fast but unreliable and risky; it doesn’t ensure the delivery of data packets.

HTTP works on top of TCP, and both of the protocols work together to ensure effective and reliable web communication.