Control which users have specific permissions to access
the data grid through the policy file.
About this task
Even if a client is authenticated, that might not be enough
to protect data grid access. If you use the KeyStoreLoginAuthenticator,
usually you only define a few identities, and all of the identities
might have full access to the data grid. In this case, authorization
might not be necessary. However, if LDAP authentication is used, there
might be many identities in the LDAP server that must not be granted
access to grid data or operations.