Can you define your own CAS groups? if Yes, How?

Yes, we can define our own CAS groups. To see the code groups defined on any system, run 'caspol -lg' from the command-line tool.

to create our own CAS group we will use caspol. For example, suppose I trust code from www.abc.com and you want it have full access to myr system, but I want to keep the default restrictions for all other internet sites.
To achieve this, I would add a new code group as a sub-group of the 'Zone - Internet' group, like this: caspol -ag 1.3 -site www.abc.com FullTrust the new group will been added