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--- HTTP/3 is coming! And it won't use TCP! ---

A recent announcement reveals that HTTP - the protocol used by browsers to communicate with web servers - will get a major change in version 3!

Before, the HTTP protocols (version 1.0, 1.1 and 2.2) were all layered on top of TCP (Transmission Control Protocol).
TCP provides reliable, ordered, and error-checked delivery of data over an IP network.
It can handle hardware failures, timeouts, etc. and makes sure the data is received in the order it was transmitted in.
Also you can easily detect if any corruption during transmission has occurred.
All these features are necessary for a protocol such as HTTP, but TCP wasn't originally designed for HTTP!
It's a "one-size-fits-all" solution, suitable for *any* application that needs this kind of reliability.
TCP does a lot of round trips between the client and the server to make sure everybody receives their data. Especially if you're using SSL. This results in a high network latency.
So if we had a protocol which is basically designed for HTTP, it could help a lot at fixing all these problems.
This is the idea behind "QUIC", an experimental network protocol, originally created by Google, using UDP.

Now we all know how unreliable UDP is: You don't know if the data you sent was received nor does the receiver know if there is anything missing. Also, data is unordered, so if anything takes longer to send, it will most likely mix up with the other pieces of data. The only good part of UDP is its simplicity.
So why use this crappy thing for such an important protocol as HTTP?
Well, QUIC fixes all these problems UDP has, and provides the reliability of TCP but without introducing lots of round trips and a high latency! (How cool is that?)

The Internet Engineering Task Force (IETF) has been working (or is still working) on a standardized version of QUIC, although it's very different from Google's original proposal.
The IETF also wants to create a version of HTTP that uses QUIC, previously referred to as HTTP-over-QUIC. HTTP-over-QUIC isn't, however, HTTP/2 over QUIC.
It's a new, updated version of HTTP built for QUIC.

Now, the chairman of both the HTTP working group and the QUIC working group for IETF, Mark Nottingham, wanted to rename HTTP-over-QUIC to HTTP/3, and it seems like his proposal got accepted!
So version 3 of HTTP will have QUIC as an essential, integral feature, and we can expect that it no longer uses TCP as its network protocol.

We will see how it turns out in the end, but I'm sure we will have to wait a couple more years for HTTP/3, when it has been thoroughly tested and integrated.

Thank you for reading!