HTTP protocols

HTTP/1.X

A discussion on optimization strategies for HTTP/1.0 is a simple one: all HTTP/1.0 deployments should be upgraded to HTTP/1.1; end of story.

Improving performance of HTTP was one the key design goals for the HTTP/1.1 working group, and the standard introduced a large number of critical performance enhancements and features. A few of the best known include the following:

• Persistent connections to allow connection reuse

• Chunked transfer encoding to allow response streaming

• Request pipelining to allow parallel request processing

• Byte serving to allow range-based resource requests

• Improved and much better-specified caching mechanisms

This list is incomplete, and a full discussion of the technical details of each and every HTTP/1.1 enhancement deserves a separate lesson. Once again, check out HTTP: The Definitive Guide by David Gourley and Brian Totty. Similarly, speaking of good reference books, Steve Souders’ High Performance Web Sites offers great advice in the form of 14 rules, half of which are networking optimizations:

Reduce DNS lookups

Every hostname resolution requires a network roundtrip, imposing latency on the request and blocking the request while the lookup is in progress.

Make fewer HTTP requests

No request is faster than a request not made: eliminate unnecessary resources on your pages.

Use a Content Delivery Network

Locating the data geographically closer to the client can significantly reduce the network latency of every TCP connection and ...