1 200 ok date fri 30 oct 1998 131941 gmt server

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: •  amazon.com aol.com cnn.com ebay.com google.com msn.com myspace.com wikipedia.org yahoo.com youtube.com Akamai Akamai •  Akamai, Mirror Image •  SAVVIS Akamai, Limelight Akamai Content DistribuOon Networks have servers around the world They distribute your content so downloads can come from a nearby locaOon Major CDN providers are –  Akamai •  –  –  –  –  –  Distributes OS X and iOS updates SAVVis Limelight OnApp BityGravity Amazon CloudFront distribute your static content before distributing your dynamic content Copyright 2009 - 2013 Horowitz 14 Rule 3: Add an Expires Header •  All caches use a set of rules to determine whether to deliver an object from the cache or request a new version –  –  –  If the object’s headers tell the cache not to keep the object, it won’t If the object is authenOcated or secure, it wont be cached A cached object is “fresh” (able to be sent to a client without checking with the server) if •  It has an expiry Ome or other age- controlling direcOve that is set and sOll within the fresh period •  If a browser cache has already seen the object and has been set to check once a session •  If a proxy cache has seen the object recently, and it was modified long ago –  If an object is “stale”, the origin server will be asked to validate the object or tell the cache whether the copy that is has is sOll good •  As part of HTTP protocol there is a Cache- Control header •  HTTP headers are sent by the server before the HTML, and only seen by the browser and any intermediate caches....
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online