HTTP is an essential backbone of the Internet — it dictates how communications platforms and devices exchange information and fetch resources. In short, it is what allows users to load websites.
HTTP/3 is a new standard in development that will affect how web browsers and servers communicate, with significant upgrades for user experience, including performance, reliability, and security.
What is new in HTTP/3?
HTTP/3 will be the first major upgrade to the hypertext transfer protocol since HTTP/2 was approved in 2015.
An important difference in HTTP/3 is that it runs on QUIC, a new transport protocol. QUIC is designed for mobile-heavy Internet usage in which people carry smartphones that constantly switch from one network to another as they move about their day. This was not the case when the first Internet protocols were developed: devices were less portable and did not switch networks very often.
The use of QUIC means that HTTP/3 relies on the User Datagram Protocol (UDP), not the Transmission Control Protocol (TCP). Switching to UDP will enable faster connections and faster user experience when browsing online.
Why is a new version of HTTP needed?
QUIC will help fix some of HTTP/2’s biggest shortcomings:
Developing a workaround for the sluggish performance when a smartphone switches from WiFi to cellular data
Decreasing the effects of packet loss — when one packet of information does not make it to its destination, it will no longer block all streams of information
Other benefits include:
Faster connection establishment: QUIC allows TLS version negotiation to happen at the same time as the cryptographic and transport handshakes
Zero round-trip time (0-RTT): For servers they have already connected to, clients can skip the handshake requirement (the process of acknowledging and verifying each other to determine how they will communicate)
More comprehensive encryption: QUIC’s new approach to handshakes will provide encryption by default — a huge upgrade from HTTP/2 — and will help mitigate the risk of attacks