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In the previous lesson we discussed HTP teus a server push feature.

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So with our server having HTP to enable Let's see a very quick example of how we might use server push.

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Note that the subject of server push can be quite extensive and very quickly creep into web development

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rather than networking.

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Therefore I'll keep this lesson very simple.

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I have however linked to some more documentation and guides in the lesson resources.

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Should you wish to learn more.

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I have the demo site open in my browser and to get a better idea of how this loads at the moment open

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the Developer Tools disabling the browser cache here just to ensure we're getting an actual server response

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reload and we get the three resources on this page indexed not actually amelle first being the main

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request which the browser passes and finds links to both style Dotti assess and thumb not be in G the

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browser requests those resources and they are delivered simultaneously over a multiplexed HTP to connection.

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What we can do with a server push implementation then is send these two files style dotsie assess and

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thumb dot P and G along with this response for indexed age dear mal.

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Note however that these browser tools isn't particularly good at displaying how pushed files are delivered.

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So instead I'll use a command line tool called N G H T T P.

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This is available for all Linux distributions or even for your local development machine.

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Should you wish to it from there.

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But to install it here on a one to using a p t I'll run apt get install n g h t t to client.

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Yes and done so detest our current implementation.

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I'll say.

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N G H T T B.

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With a couple of flags.

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N to discard the responses.

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Meaning we're only testing them and not saving them to disk.

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Why to ignore the self science certificate and S meaning print the response.

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Statistics.

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Which is exactly what we're interested in.

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Post that indexed out h.t. email you are role enter and we see here.

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A simple response breakdown confirming that only indexed.

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The email was downloaded.

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Do that same test again this time.

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Adding in a flag meaning also request linked assets for this request so styled as is and fund or be

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injy enter.

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And again as with the browser we see from the timings that these two files were requested and downloaded

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at the same time immediately after receiving indexed HD email what we want to achieve then is to run

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the first test.

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So not requesting these two linked files but still receive them as a result of requesting indexed Odd

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h.t. a mile over to the engine configuration file.

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I'll add a new location.

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Make this an exact match for indexed HD Mel.

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Very importantly however slash indexed h.t. email exactly as we're requesting it.

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In which case will perform an H TTP to underscore push or slash style dotsie Yes and the same for Slash

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thumb.

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Don't be in G.

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That's very rudimentary but essentially all we need to push these two files when indexed hard edged

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here mail is requested.

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Note that we are not specifying the resource itself but rather the request for the resource.

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An important distinction.

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Save reload the configuration.

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Run that first test with out the a flag.

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So the one that only gave us indexed updated here Mal enter and this time we get all three files automatically

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with this asterisk indicating a pushed response.

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Also note the significant reduction in process times and the total time for these linked resources to

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be received.

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So overall a much faster and more efficient way of delivering Web based content for both the server

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and the client.