sunshine737
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How a Proxy Cache works?
hi,
Proxies aim to improve the performance offered by the Web, providing end users with faster access to its resources.
my question is like when a webpage is accessed the contents of the page remains in the proxycache. when another user requests the same page it is given to the user from the cache. in case if the contents of the page is changing every time (like some thing i buy in www.ebay.de) in this case how it works.
any ideas welcome.
Proxies aim to improve the performance offered by the Web, providing end users with faster access to its resources.
my question is like when a webpage is accessed the contents of the page remains in the proxycache. when another user requests the same page it is given to the user from the cache. in case if the contents of the page is changing every time (like some thing i buy in www.ebay.de) in this case how it works.
any ideas welcome.
I'm sure it depends on what software you are using for the caching. My experiece is that you should be able to configure the proxy to check the requested page on the internet. If the page has not been changed, then it issues the page from the cache to the requestor, otherwise, it recaches and then issues to the requestor.
Jared
Jared
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ASKER
hi,
By configuring the proxy to check if the page is requested is changed or not. it takes the same time to redirect the request and get the page from the main server.
am i right..
can u provide me with some links which explains this mechanism.
By configuring the proxy to check if the page is requested is changed or not. it takes the same time to redirect the request and get the page from the main server.
am i right..
can u provide me with some links which explains this mechanism.
ASKER
Hi muhalok,
thanx for ur explanation. i have some doubts u have given expires, for each and every request it check whether the pages expires r what?.r only if the page has the dynamic content it checks??.
thanx for ur explanation. i have some doubts u have given expires, for each and every request it check whether the pages expires r what?.r only if the page has the dynamic content it checks??.
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ASKER
Hi,
can u help me in giving some links.
can u help me in giving some links.
ASKER
one doubt
suppose if there is a page in the cache and if the page is changed in the mainserver the page in the cache is no more valid , what happens to that page it remains in cache and deleted after some time r the new page is replaced instead of old page.
suppose if there is a page in the cache and if the page is changed in the mainserver the page in the cache is no more valid , what happens to that page it remains in cache and deleted after some time r the new page is replaced instead of old page.
the expired cache contents is replaced by any new content upon a request from the client , i.e. - when client sends for example an HTTP GET request for the content - it will send it with "If-Modified-Since <Time of download>" to the server and this request of course will be forwarded to the Server by Cache Proxy. In case that content is not modified - Server answers with HTTP 304 - Not Modified, else - server answers with HTTP 200 OK and sends the new content - which is cached and replaces the old files.
ASKER
from web search, i found some info regarding proxy cache.
there is a mechanism for the proxy to check with the remote site, before it gives you a copy it pulled earlier, to make sure the page hasn't changed since.
but i didnot found ,how the above mechanism works . :(
if any links/notes are appreciated.