QUIC is a new communication transport protocol that features reduced latency, greater reliability and security than the currently widely used TCP (RFC 793).
Already much has been said about the advantages of the QUIC transport, which is taken as the basis for the future HTTP / 3 standard . In next-generation HTTP, the TCP transport is changed to QUIC, which means automatically speeding up connections and encrypting all Internet traffic that used to go in clear text over TCP. Unencrypted QUIC is not provided at all.
In May 2021, a significant event took place: the QUIC protocol was adopted as the official RFC9000 standard . This is great news for the entire internet ecosystem.
These standards are approved by the Internet Engineering Task Force (IETF). Ancillary standards RFC 9001 , RFC 9002 and RFC 8999 were previously issued .
Thus, QUIC version 1 is now officially accepted and approved. All parties involved can finish experimenting with draft minutes and move to the first official version .
QUIC has been one of the top priorities for the IETF in recent years. Emerging as a Google experiment, QUIC's development soon went international. It was conducted for almost five years... There were 26 face-to-face meetings , 1,749 tasks in the tracker and many thousands of letters in the mailing list.
QUIC is a very ambitious project that will bring big changes. “The Internet's transport ecosystem has become ossified over several decades, and QUIC will revitalize it,” write engineers at Fastly, who are part of the protocol development working group.
Ossification means that every year the system becomes less flexible, less mobile. QUIC will bring many innovations to the transport layer, including mandatory encryption, versioning, a much richer and more productive set of services on top of which new technologies will be built. QUIC is expected to lead to the next generation of internet innovation. This is already beginning to happen with extensions such as the Unreliable Datagram Extension. Untrustworthy datagrams open the door to a new class of real-time media and other applications that need more functional transport than obligatory packet delivery with a drop in the link when a few pixels are lost. We are already seeing promising technologies such as MASQUE and WebTransport .
HTTP / 3
The HTTP / 3 standard (this is HTTP over QUIC) follows QUIC with a slight delay and will also be officially adopted in the very near future.
34th (!) Draft HTTP / 3
Six years have passed since the adoption of HTTP / 2: the RFC 7540 specification was published in May 2015, but is not yet widely used. The protocol has been implemented in all browsers since the end of 2015, and three years later, only 45.4% of the 10 million most popular Internet sites support HTTP / 2. Two and a half years ago, this figure was 31.2% . Recently, the sites Amazon, Paypal, Telegram.org moved to HTTP / 2.
Now the third version of HTTP / 3 is almost ready, it remains quite a bit to wait.
QUIC is a TCP replacement that runs on top of UDP. This technology was originally created by Google engineers, like the previous SPDY protocol, which became the basis for HTTP / 2. At first, QUIC was called “HTTP / 2-encrypted-over-UDP”.
Then the development of QUIC was submitted to the IETF for standardization. Here it is divided into two parts: transport and HTTP. The idea is that the transport protocol can be used to transfer other data as well, not just exclusive to HTTP or HTTP-like protocols. However, the name remained the same: QUIC. The transport protocol is being developed by the QUIC Working Group in the IETF.
For a long time, the IETF version was called iQUIC, while Google and others continued to work on their own implementation of gQUIC, but on November 7, 2018, one of the leading developers of the protocol, Dmitry Tikhonov, announced that the parties had achieved protocol compatibility, and now the development will continue in the general direction. QUIC in Chrome is enabled in the chrome: // flags settings . There is also an indicator extension that shows which sites support QUIC.
Built-in security and performance
What are the advantages of the QUIC transport protocol over TCP? There are many advantages. The move from legacy TCP to new protocols is inevitable, according to working group leader Mark Nottingham, as it is now clear that TCP is suffering from inefficiency issues.
“Because TCP is a sequential packet delivery protocol, the loss of one packet can prevent the application from delivering subsequent packets from the buffer. In a multiplexed protocol, this can lead to a large loss of performance, explains Mark Nottingham. "QUIC is trying to solve this problem by effectively rebuilding TCP semantics (along with some aspects of the HTTP / 2 streaming model) over UDP."
In addition to the transition of a significant amount of traffic from TCP to UDP, the QUIC protocol requires mandatory encryption: an unencrypted QUIC does not exist at all. QUIC uses TLS 1.3 to set session keys and then encrypt each packet. But since it is UDP-based, much of the session information and metadata exposed in TCP is encrypted in QUIC.
In The Future of Internet Protocols, Mark Nottingham talks about the significant security improvements with the move to QUIC:
« » iQUIC — , — , , ( ). — ACK, .
, RTT ; .
. , .
— -. , -, RTT. , , .
Perhaps the adoption of the QUIC standard would have happened earlier, if Google had not rushed to implement its implementation in the Chrome browser, so a “bifurcation” of the standard happened.
Nevertheless, progress is inevitable - and in the coming years, standardization and widespread implementation of various new generation protocols, including HTTP / 3 on QUIC transport, will certainly continue.
See also:
- "HTTP / 3: From Root to Tip"
- The Future of Internet Protocols by Mark Nottingham
Celebrate GlobalSign's Anniversary and Get Discounts!
