Problem with inbound calls with unknown call number

[Il Kwon Jang]

Hi,

I have problem with inbound calls with unknown call numbers and the customer is suffering from a ringing sound.

How can i reject with unknown call numbers.

The customer site network design is as below

EX90-----VCS--F/W--VCSE---Internet

Can anyone give some suggestions for me please?

Many Thanks

[Paul Woelfel]

Hi, you could use CPL to block calls. If you look at the call history, which source aliases do you see?

[ahmashar]

on CPL script  add somthing like this:

"0(\d.*)" should be your internal dial plan number. you can open a TAC case for customized script that suits your setup.

regards, Ahmad

[Martin Koch]

If the endpoint has number 100, 101, 1000 or something similar round I would simply think about changing the address first.

Anyhow I would check what calls cause this to better block the problem.

If the endpoint is on a public ip or some static Nat is setup it can also be that the unwanted calls go directly to the endpoint.
Blocking sip udp can be helpful in such cases (or remove the direct reach ability of the system if its registered to a vcsc)

Sent from Cisco Technical Support iPhone App

[adimchev]

Hi Il Kwon,

I am not really sure if blocking all the inbound calls from “unknown” numbers is good idea, it defeats the whole purpose of being available for someone who would like to call you from outside.

There should be a source alias and as Paul pointed out may be you should block only those,

Another way is define (via CPL) source aliases allowed to go through the VCS expressway and deny everything else or alternatively deny all the traffic on the perimeter firewall with source of the intruder.

Regards//Andrey