Advanced configuration

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This option is designed for advanced users only and allows a degree of flexibility well beyond what most people will require. The majority of users can safely leave it well alone!

When you visit a web page, the various filters each make an independent decision whether it should be blocked or allowed. One of three possible results is returned by each filter to the central ICRAplus unit:

All the allow, block and don’t know messages must be reduced down to a global decision by ICRAplus to block or allow the page. You can choose how this is done. Each of the 3 possible output messages from an individual filter can be used by ICRAplus directly to block or allow access to a page irrespective of other filters, can be ignored, or can be put into a voting system.

For example, you may feel that a particular filter can be trusted to block certain types of content but you don’t trust its allow decisions. You can therefore configure ICRAplus to ignore it if it says allow or don’t know, but block the page if that filter says block.

Using this system, it is possible for ICRAplus to be faced with directives to block and allow the same page. In this case, the priority system is used to resolve the matter. So, for example, a priority 1 “block” will override a priority 2 “allow.” Only one filter may be set at each priority level. By default, priorities are assigned in the order in which the filters were installed, the earlier a filter was installed, the higher its priority.

As well as the basic block/allow mechanism, there is a more sophisticated voting system available. The output messages of each filter can be fed into the voting system with values, and therefore voting power, set by you. If the result of the vote is 0 or a positive number, the page is allowed. If it is negative, the page is blocked. Don’t worry, this voting system does not slow down your surfing!

Finally, despite the best efforts of the installed filters, it is possible that the global response is still “ignore.” Since ICRAplus must give a definite block or allow response, you can configure whether a page should be blocked or allowed in this situation. This is done through the “If the global response is ignore then block/allow” options.

Remember to save any changes you make before leaving this screen!