Google announced few days ago it has already started with the deployment of HTTP / 3 and IETF QUIC in Chrome and in the announcement, he states that he expects this update to bring some additional performance improvements, especially with support for QUIC.
QUIC is a new network transport protocol which combines the features of TCP, TLS and more. HTTP / 3 is the latest version of HTTP, the protocol that carries the vast majority of web traffic. HTTP / 3 only works on QUIC.
The Internet Engineering Task Force, or IETF, introduced HTTP / 2 in 2015 and one of the big improvements it made is support for multiplexing.
However, it used TCP as the transport protocol and the loss recovery mechanisms in TCP, so lost packets can still cause a delay in all active transactions.
By adopting QUIC, HTTP / 3 can further improve the transfer process, since the lost packets in this case only affect the directly affected transactions.
In fact, QUIC was originally developed by Google and first announced in 2013. Since then, the protocol has come of age and is currently responsible for carrying a third of Google's traffic.
Then, in 2015, the development of QUIC passed into the hands of the IETF, the standards body responsible for maintaining Internet protocols. The IETF has improved QUIC with several changes. To date, there are two similar, but different protocols, which are: Google QUIC and IETF QUIC.
Google has announced that it has always used its own version of QUIC, but that his QUIC team is also involved in the implementation of the proprietary version of the IEFT. "We have made significant efforts to evolve Google QUIC over the past five years to keep up with the changes made by the IETF, and the current latest version of Google QUIC has many similarities to IETF QUIC," the blog post reads. from Google, in addition, clarified that some things were still missing.
As an example, so far most Chrome users cannot communicate with IETF QUIC servers without enabling some command line options. Likewise, Google added that it has now found that IETF QUIC significantly outperforms HTTP compared to TLS 1.3 compared to TCP.
In particular, the company said that Google's search engine latency is reduced by more than 2%. YouTube's buffering time has been reduced by more than 9%. Additionally, client performance has increased by more than 3% on desktop computers.
On mobile phones, customer performance increased by more than 7%. These and other reasons are behind Chrome's switch to the QUIC version of the IETF. “We are pleased to announce that Chrome is implementing support for IETF QUIC (specifically, the h3-29 pilot version).
Today, about 25% of users of the stable version of Chrome are using h3-29, and we plan to increase this number in the coming weeks by continuing to monitor performance data, ”the company said in its blog post. .
"Chrome will actively support both the IETF QUIC h3-29 and the Google QUIC (Q050) version to allow time for servers that support Q050 to upgrade to IETF QUIC," he added. Chrome m85 does not yet support IETF QUIC 0-RTT and Google expects this performance to be even better when it releases support for IETF QUIC 0-RTT in the coming months. Also, since IETF QUIC versions 30 and 31 do not contain changes that could break compatibility, the company does not plan to change the identifier "over-the-wire."
This means that will continue to track changes in the IETF version, but the will implement as h3-29 / 0xff00001d.
Therefore, it recommends that servers continue to support h3-29 until final RFCs are completed if they want to interoperate with Chrome. However, if the IETF makes changes that break compatibility in a future project, Chrome will reverse that decision.