The HTTP specifications explain HTTP messages fairly well, but they don’t talk much about HTTP connections, the critical plumbing that HTTP messages flow through. If you’re a programmer writing HTTP applications, you need to understand the ins and outs of HTTP connections and how to use them.
HTTP connection management has been a bit of a black art, learned as much from experimentation and apprenticeship as from published literature. In this chapter, you’ll learn about:
How HTTP uses TCP connections
Delays, bottlenecks and clogs in TCP connections
HTTP optimizations, including parallel, keep-alive, and pipelined connections
Dos and don’ts for managing connections