Call block by name (not number)

[RBS]

For some reason everything blocked by name is getting through.

Example of incoming call: V9180747220007084083 (8482173553)

We'd like to block
V91*

I'm guessing maybe some incoming parameter is not being passed correctly?

Telnyx SIP, if it helps any.

 

[craigreilly]

the Block by Number screen is just that... block by number - not name.

 

[RBS]

According to this article
https://www.3cx.com/docs/trap-and-block-anonymous-callers/
you should be able to, unless "anonymous" a reserved keyword.
If it's not, technically it should work for other "words" as well.

 

[complex1]

Hi,

Please try Inbound Rules > Add CID Rule and under Caller ID field add V91*
This should also work in Settings > Blacklisted Numbers
I have test it with incoming anonymous caller ID. Blacklist filled with "*nonymous" blocked the call.

 

[RBS]

I have tried it both ways that you suggested, and neither works.

I think some inbound parameter being passed is not acknowledged and checked for blocking.

Caller ID Name/Number is working fine, but it seems it pays no attention to the Name part, as far as blocking is concerned.

 

[complex1]

Hi,

Then try (at your own risk) to change the Inbound Parameters of the SIP Trunk (red dot)

 

[RBS]

Well, "technically" that blocked the call, but now CallerNum is gone.

How do we see the number that made the calls?

We need to go deeper

 

[craigreilly]

According to this article
https://www.3cx.com/docs/trap-and-block-anonymous-callers/
you should be able to, unless "anonymous" a reserved keyword.
If it's not, technically it should work for other "words" as well.

Well perhaps they should update the GUI a bit.

 

[complex1]

Hi,

Do you have both “CallerName” and “CallerNum” set to “From: Display Name”?

 

[NickD_3CX]

According to this article
https://www.3cx.com/docs/trap-and-block-anonymous-callers/
you should be able to, unless "anonymous" a reserved keyword.
If it's not, technically it should work for other "words" as well.

I can see the logic you followed, unfortunately though it is not quite like this.
"anonymous" is a special value providers send instead of the number when the caller ID is withheld. So in this case, in the Number blacklist you would actually write a text string, because that is being sent instead of a number.

On a more technical note, on incoming calls, the "From" has 2 values, the:

• Display Name: optional field that can contain text, usually used to deliver the CNAM
  
• User Part: mandatory field, that can also contain text in ASCII, but 99.9% of the times contains the CNUM (or 'anonymous')

With the Inbound Parameters you tell 3CX where to read the "CallerName" and "CallerNum" from.
"CallerNum", 99% of the times is taken from the "User Part".

Now the Number Blacklist blocks based on the value contained in the "CallerNum"

So, why I explained all this:
You could set the CallerNum to the Display Name, but it would be encoded in ASCII, but technically you could then use the Number Blacklist with names.
Note: You would completely break the re-dialing function, and if it doesn't work, don't report it because it this way is a complete misuse of the way the feature was meant to work.

Update:
You could request this though in the "Ideas" section as a new feature, "Caller Name Blacklist" which would work like the number blacklist, but based on the Callers Name

 

[RBS]

.

Thank you NickD, very informative. I didn't realize it's a "either/or" situation and only only runs it against one parameter.

Considering the massive-scale plague of robocalls, this idea implementation would likely be very welcome by many.

 

[leejor]

My experience, with "unsolicited calls', is that many now simply send the same number, in the name field. They make sure it is the same area code, and prefix, as the number they are calling (your number) as they feel this gives them the best chance of reaching you. It appears to be a local call. I rarely see the same number used more than once, to the same destination.

If the "group" calling you is sending a name, that allows you to screen and block the calls, then great, it would make a useful feature addition, please suggest it. Sadly, the ones calling me, are not that dumb.

 

[RBS]

Well, with everything said, I'm curious whether the blocked numbers a re processed as integers or strings? (anonymous = hard-coded string?).

I can see how problems might arise with matching strings on high call volume installation, but it could be a workable opt-in feature you could enable/disable at will for modest needs.