Simply, "Call barring" is used to block certain incoming or outgoing calls. It is widely used in enterprise communication. For example, PBX need limit some extensions to make out-group calls. Of course, it is often required to block some outside spam calls too.
In MSS, there are several methods to provide 'call barring', such as 'system black list', 'call level' and so on. We can combine these method to fit PBX 'call barring' requirements flexibly.
It is very easy to use "system black list" to block incoming calls. Please refer to "system black list" document for more details.
It means we want to limit local users (extensions) to make outgoing calls. In fact, we can still use "system black list" to do that. Here we introduce another method to do it perfectly. It is "call-level" feature.
For example, local users dial "9xxxx" to make out-group calls. We hope MSS to reject some local users to make such calls.
Please click menu "dial plan / analyze called number" to add a record whose 'call-level' is 1 which is illustrated in below figure.
It means local user must have 'call-level 1' right to make out-group calls, otherwise, MSS will reject them.
Please add or edit 'Basic call' of local user configuration as below if we want it be able to make such calls.