In an attempt to avoid these issues, SPDY uses a single SSL-encrypted session between a browser and a client, and then compresses all the request/response overhead. The requests, responses, and data are all put into frames that are multiplexed over the one connection. This makes it possible to send a higher-priority small file without waiting for the transfer of a large file that’s already in progress to terminate.
via SPDY: Google wants to speed up the web by ditching HTTP.
This article is two years old.