

It is an experimental flag and if you face any issues, please disable the flag. This greatly reduces the time taken to transfer data packets, which improves the data exchange speed and hence the overall internet connectivity speed. It makes it possible to create a single trip between client and server. When these two combine together, it gives not only a much faster browsing experience but also provides a much safer experience. This protocol is a mixture of both TCP and UDP protocols. Although you might not experience a ton load of improvement in speed, still it has a noticeable impact.

There is an Experimental Chrome Flags called QUIC protocol.
