Eliminating Roundtrips with Preconnect

1 ยท Ilya Grigorik ยท Aug. 17, 2015, 7 a.m.
The "simple" act of initiating an HTTP request can incur many roundtrips before the actual request bytes are routed to the server: the browser may have to resolve the DNS name, perform the TCP handshake, and negotiate the TLS tunnel if a secure socket is required. All accounted for, that's anywhere from one to three โ€” and more in unoptimized cases โ€” roundtrips of latency to set up the socket before the actual request bytes are routed to the server. Modern browsers try their best to anticipate w...