Original URL: http://www.theregister.co.uk/2013/07/10/http_20_ietf_draft_lands/

HTTP 2.0 interop tests slated for August

Google fooling around with next protocol

By Richard Chirgwin

Posted in Networks, 10th July 2013 01:29 GMT

Fresh from seeing its SPDY protocol adopted into the IETF's HTTP 2.0 draft, Google is pressing on with its quest for faster Interwebs with an experimental protocol called QUIC (Quick UDP Internet Connections).

HTTP 2.0 (draft here) proposes a number of changes compared to HTTP 1.1 to cut latency for Web applications, without breaking the familiar semantics of HTTP.

A major change is binary framing. This is not HTTP 1.1 compatible, but since it's designed to be handled in browser and server, it should be invisible to users. The other is full request multiplexing, replacing the older one-request-at-a-time model.

Infoworld reports that interop testing for HTTP 2.0 is slated for August, which means it's on track for its planned 2014 rollout.

In this Chromium blog post, Google's Jim Roskind argues that that's not enough: he argues that round-trip-times (RTT) will remain a problem, particularly on mobile networks. So the Chocolate Factory is looking at another protocol, QUIC, which would move traffic from TCP to UDP.

A host of factors contribute to RTT: signal propagation delays (the speed of light in optical and copper media), the number of router hops between two parties, the congestion and capacity of those routers – these aren't accessible to the Web user or the server.

However, the way that clients and servers handle Web sites also contributes to RTT, Roskind writes. Anything that requires packet retransmission – packet loss or errors – increases the RTT observed at the client, so these are dealt with by error correction and “packet pacing”. QUIC also proposes using UDP transport instead of TCP “to avoid TCP head-of-line blocking”.

There's a lot more on QUIC here. ®