Each account can have a table of codes to allow or deny. These work rather like an LCR whereby the most specific matching code applies. This enables very granular blocking of traffic, e.g.:
If no ACLs are specified then 'allow' is assumed. If a generic deny is set then if more specific codes are to be permitted, appropriate allow rules must be set as in the example above. The best use of this is to apply your very high level policy including your own list of blocked numbers.
Alongside each trunk the “truck destination ACL” option works in the same way as the account level one above, but at trunk level: