By Ilya Grigorik on October 04, 2011 The last major update to the HTTP spec dates back to 1999, at which time RFC 2616 standardized HTTP 1.1 and introduced the much needed keep-alive and pipelining support. Whereas HTTP 1.0 required strict "single request per connection" model, HTTP 1.1 reversed this behavior: by default, an HTTP 1.1 client and server keep the connection open, unless the client in