Block Incoming calls based on calling party number CUCM

Are you annoyed of unwanted calls? Trying to block incoming calls based on the Calling Party Number?  Time to play with “Route Next Hop By Calling Party Number” which block calls based on calling party number. This feature works for all the protocols like MGCP, H323 and SIP as well.

Scenario:-
Calling Party Number – 99999 (External PSTN)
Called Party Number – 10000

In Figure 1 – When “Route Next Hop By Calling Party Number” is not applied, the calls are getting routed to extension 10000.

In Figure 2 – When “Route Next Hop By Calling Party Number” is applied, the calls are not being sent to the extension 10000 by Cisco Unified Communication Manager.

To achieve this functionality, you need to follow the below steps –

Configuration in Cisco Unified Communication  Manager:

• Login to Cisco Unified Communication Manager.

Create Partitions and CSS

• Create a Partition named “Gateway_PRT” and Create a CSS name “Gateway_CSS”. Assign Gateway_PRT to Gateway_CSS
• Create a Partition named “Filter_PRT” and Create a CSS name “Filter_CSS”. Assign Filter_PRT to Filter_CSS

Note : Ensure that Gateway CSS should not have any other Partitions that is being used by Directory Numbers, else the calls will be routed to the Directory Numbers.

Assign Gateway_CSS in Trunks and Gateways for Inbound Calls

Create Translation Pattern > This Translation Pattern will match all the incoming calls from Gateways or Trunks

• Add a New Translation Pattern > !
• Description > Calls from Gateways or Trunks
• Calling Search Space > Filter_CSS
• Check Mark > Route Next Hop By Calling Party

Create Translation Pattern > This Translation Pattern will route non blocking calls to the Directory Numbers

• Add a New Translation Pattern > !
• Description > Filtered Translation Pattern
• Calling Search Space > Internal_CSS (Calling Search Space of IP Phones/Directory Numbers)
• Ensure Route Next Hop by Calling Party is Unchecked

Create Translation Pattern > This Translation Pattern will block calls to the Directory Numbers

• Add a New Translation Pattern > 99999
• Description > 99999 is Being Blocked to Call to the Directory Numbers
• Calling Search Space > <None>
• Route Option > Block this Pattern > Call Rejected
• Ensure Route Next Hop by Calling Party is Unchecked

Now the calls from 99999 will be blocked when the call hits Cisco Unified Communication Manager.
Cheers!!

Avinash Karnani

I am working in an IT company and having 10+ years of experience into Cisco IP Telephony and Contact Center. I have worked on products like CUCM, CUC, UCCX, CME/CUE, IM&P, Voice Gateways, VG224, Gatekeepers, Attendant Console, Expressway, Mediasense, Asterisk, Microsoft Teams, Zoom etc. I am not an expert but i keep exploring whenever and wherever i can and share whatever i know. You can visit my LinkedIn profile by clicking on the icon below.

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