Rabu, 18 April 2012

Proxy Server on Squid

Is it transparent cache?
Explanation of terms transparent and transparent proxy cache depends on the instance, but we assume here that the context of HTTP Proxy / cache with transparent hijacking of port 80 which is an HTTP path that failed in the internet. The difference is that the cache include cache, but the proxy only proxies without caching. Transparent Overload has different meanings depending on the situation. The word can mean a plow setup port path 80 where klientnya try to go to another server, can also mean a transparent proxy which can not change the meaning / content of the request. there is no tool like transparent proxy, only the semi-transparent and there is no such tool trasnparan cache. Squid can be configured to act in a transparent. In this mode the client is not required to configure their browser to access the cache but squid will pick the right package and request a transparent cache.

Thing that can solve the biggest problem with using caching: encourage the users to use the cache server.

Advantages transparent caching:
Advantages and disadvantages of transparent caching completely the opposite of all that has been mentioned in the example for proxy caching. Advantage, the administration made easy to understand browser does not have to be configured to talk to the cache. Control center, users can not change the browser to complete the cache.

Losses transparent caching:
Not strong, because transparent caching depends on a stable path routed between the client with the original serveryang, in terms of path through the cache. This is the internet easily influenced to change - change in routing. In other words, if a relationship between the client with the cache set and routing changes occur which cause the client to take a path that no longer flows through a network of diverting, periods will stop and the user must fill out the page, if the routes in the internet then the result is uncertain will be more unpredictable.

User control,
Transparent caching takes away control from the user. Some users have biases are very strong and will change the ISP caching too late to avoid it.


Dependencies browser,
For transparent many successful operation depends on the browser cache provides a number of the original server name in the HTTP request header. This is necessary because the cache was not able to access the destination server IP address from the IP address of the original package, for that reason the cache disappeared. They could not determine the address of the original server to send permintaan.Beberapa initial browser / previously not provide this information and therefore will not work properly with transparent cache, but 90% of the browser puas.Dalam fact, many have observed that complement the network number HTTP is a significant demand for non cachetable fill (35-45%). Occurrence rate is proportional to the amount of cache contents are sent to non cachetable cache.