programming
Back to the Future: HTTP 2.0
L
et’s have a quick look over the history and development of the HTTP protocol (Hypertext Transfer Protocol), in order to better understand the modifications proposed for the 2.0 version.
The need for evolution of the HTTP protocol Rareș Rusu
rares.rusu@betfair.com Inginer Software @ Betfair România
HTTP is one of the protocols that have nourished the spectacular evolution of the Internet: it allows the clients to communicate with the servers, which is the base of what the Internet is today. It was initially designed as a simple protocol to ensure the transfer of a file from a server to a client (the 0.9 version, proposed in 1991). Due to the undeniable success of the protocol, billions of devices are able to communicate these days using HTTP (the current version 1.1). The extraordinary diversity of content and of the applications available today, together with the users’ requirements for quick interactions push HTTP 1.1 beyond the limits imagined by those who designed it. Consequently, in order to ensure the next leap in the performance of the Internet, a new version of the protocol is required, to solve the current limitations and to allow a new class of applications, of a greater performance.
back (round trip) Broadband (Bandwidth) - The maximum capacity of a communication channel As an analogy to the bathing installation of a house, we can consider the broadband as the diameter of a water pipe. A larger diameter allows more water to pass through. On the other hand, in the case where the pipe is empty, no matter its diameter, the water will reach its destination only after going through the entire length of the pipe (the latency). It’s intuitional to judge the performance of a connection according to its broadband (a 10 Mbps connection is better than a 5 Mbps one), but the broadband is not the only factor responsible for performance: in fact, due to the particularity of web applications to use several short duration
Latency versus broadband
The latency and the broadband are two features that dictate the performance of the traffic of data on the network: Latency (one way/ round trip) - the time from the source sending a packet to the destination receiving it (one way) and
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no. 21/March | www.todaysoftmag.com
Picture 1. The evolution of the uploading time for a page (milliseconds) depending on the broadband (Megabit/s), by Mike Belshe - More Bandwidth Doesn’t Matter (much)