hwo is HTTP pipelining used

[rookie1010]

Hello,

I am trying to understand how HTTP pipelining is used?

would a request to say the home page for www.cnn.com results in one HTTP request, in which case is it correct to say that if i am opening up multiple pages e.g. www.cnn.com, www.reuters.com, www.time.com, this will result in 3 HTTP requests and necessitate a need for HTTP pipelining?

 

[bsobel]

Originally posted by: rookie1010
Hello,

I am trying to understand how HTTP pipelining is used?

would a request to say the home page for www.cnn.com results in one HTTP request, in which case is it correct to say that if i am opening up multiple pages e.g. www.cnn.com, www.reuters.com, www.time.com, this will result in 3 HTTP requests and necessitate a need for HTTP pipelining?

Most browsers open up only N connections to a web server (IE6/7 is 2, IE8 is 6). Each of those connections can grab content. When piplelining is off, the connection is closed between requests. When its on the connection stays open so the browser can issue additional requests without resetting up the TCPIP connection.

Bill

 

[rookie1010]

thanks for the reply,

my understanding is that a persistent connection is required for pipelining?

how long can a persistent connection remain open for?

when does IE6/7 use the second connection, i guess if i were to open cnn.com, reuters.com simultaneously on IE6, it would necessitate the use of one connection, what would necessitate the use (opening) of a second connection?

 

[bsobel]

en does IE6/7 use the second connection, i guess if i were to open cnn.com, reuters.com simultaneously on IE6, it would necessitate the use of one connection, what would necessitate the use (opening) of a second connection?

If you opened cnn and reuters, those would be two seperate connections no matter what. As an example, you connnect to cnn.com. The home page has 14 items [example, I havent counted] (graphics, css, scripts) that get loaded as part of loading the page up. Those 14 items get loaded up over 2 connections to cnn.com (over 6 connections if on broadband in IE8)

 

[rookie1010]

thanks for the reply,

so if i was to open only www.cnn.com, IE7 would open up both connections, since there are multiple items to open up resulting in multiple requests.
if it was a less intensive page then probably a connection woudl do.

IE8 speeds up things by opening up upto 6 connections. does this mean when peopel switch to IE8, servers would be overburdened with connection requests?

 

[bsobel]

Originally posted by: rookie1010
thanks for the reply,

so if i was to open only www.cnn.com, IE7 would open up both connections, since there are multiple items to open up resulting in multiple requests.
if it was a less intensive page then probably a connection woudl do.

Correct.

IE8 speeds up things by opening up upto 6 connections. does this mean when peopel switch to IE8, servers would be overburdened with connection requests?

Possibly, it open them up to 3x the connections. MS has done some work to find a good compromise level between user experience and server requirements. They believe 6 is a good middle ground.

Bill

 

[rookie1010]

thanks for demystifying multiple connection support

 

[mcmilljb]

http://en.wikipedia.org/wiki/HTTP_pipelining

They have a good picture on the wikipedia page.
The key to pipelining is the multiple requests without waiting for a response.
It's not about multiple connections, although multiple connections with pipelining would increase speed.

Your previous post.
Pipelining is why you would need less connections, thus tying up less resources.

Are you taking a network programming class? Your recent posts remind me of my Network Programming class.

 

[rookie1010]

thanks for the reply,

no class here, i am trying to understand networking for my current project at work. the way i am having it, dont be surprised if i start asking java queries in a few months

 

[mcmilljb]

Sun is dragging Java down lately. They need to spend more time documenting and providing more/better tools to developers. Hopefully they don't drag down MySQL.

 

[spidey07]

OK - so since this is the networking forum...and it seems like developers who have not clue a what is actually happening. Surprise! Surprise!

This NEVER happens!!!! Can you believe that application developers do not understand basic computing??!! Where the hell did they get their education from? And whats funny is the basic lack of understanding is the problem.

rookei1010, fix your application because it's obvious that you don't understand it. If you did you wouldn't be asking these questions.

It gets really old telling developers and coders what to do.

 

[Nothinman]

It gets really old telling developers and coders what to do.

Aye.

 

[rookie1010]

thanks for the reply,

i am not a developer but more of a marketting interface with a bit of technical background.

thanks for the insights guys.