HTTP pipelining appeared in HTTP/1.1. It allows clients to send multiple requests at once, without waiting for an answer. Servers can send multiple answers without closing their socket too. This results in fewer roundtrips and faster load times. This is particularly useful for Satellite Internet connections and other connections with high latency as seperate requests need not be made for each image/Javascript file etc.

Since it is possible to cram several HTTP requests in the same TCP packet (the average MSS, or maximum segment size, being 512 bytes), fewer TCP packets are sent over the network, so pipelining benefits network load too.

HTTP Pipelining requires both the client and the server to support it. A server is required to support it in order to be HTTP/1.1 compliant. Recent versions of the Apache HTTP Server support it.

How to enable HTTP pipelining in Firefox

1. Go to about:config

2. Scroll down to network.http.pipelining

3. Double click it so its value is set to "true"

4. Double click network.http.pipelining.maxrequests & enter a value into the box (20 to 40) and click OK.

External links

• A faq on pipelining, courtesy of mozilla.org: http://www.mozilla.org/projects/netlib/http/pipelining-faq.html
• A w3c page measuring the benefits of pipelining, along with modern design technologies (CSS and png): http://www.w3.org/TR/NOTE-pipelining