This document covers the Technotes for Blocking calls in Cisco Unified Communications Manager (CUCM) 8.x and later based on Automatic Number Identification(ANI) when CUCM is using MGCP Gateway.
- ANI (Automatic number identification) is a feature of telephony intelligent network services which permits subscribers to display or capture the telephone numbers of calling parties.
- DNIS (Dialed Number Identification Service) is a telephone service that identifies for the receiver of a call the number that the caller dialed. It's a common feature of 800 and 900 lines. If you have multiple 800 or 900 numbers to the same destination, DNIS tells which number was called.
When CUCMs are using MGCP gateways instead of H.323 gateways blocking calls based on ANI or Calling Number becomes difficult or not possible in older Cisco Unified Communications Manager (CUCM) versions which is below 8.x
From CUCM 8.x and later versions this task can be accomplished by using “Route Next Hop By Calling Party”
- If an MGCP gateway is used, from CUCM 8.x and later versions incoming calls can be blocked based on ANI or Calling Number. In the Older version of CUCM which is below 8.x, the only way to block unwanted calls is based on the DNIS information.
Block calls based on ANI in CUCM 8.x when CUCM is using MGCP gateway
MGCP GW -> inbound calling CSS called “Screen_all-incoming_calls_ANI_CSS” -> match to Translation pattern ! which has
“Route Next Hop By Calling Party” checked which changes the behavior to route the calls based on Calling number not the called number to next Calling search space called -> “block_certain_ANI-calls_CSS” -> which matches following transalation patterns shown as an example,
The CSS “block_certain_ANI-calls_CSS” should see following translations:
1) ! translation pattern with a CSS contains “All Phones partition” – This allows calls to route normally into the cluster.
2) 8001201 Blocking Pattern – Block calls coming from caller ID 8001201
3) 8601202 Blocking Pattern – Block calls coming from caller ID 8601202
Block calls based on ANI and DNIS when CUCM is using H.323 gateway
If an H.323 gateway is used, incoming calls can be blocked based on either Automatic Number Identifier (ANI) or Dialed Number Identification Service (DNIS) information, or both, through translation rules on the gateway (GW) configuration.
For an example of how to block calls based on specific calling numbers (ANI), refer to the Call Blocking Specific Calling Numbers
For an example of how to block calls based on specific called numbers (DNIS), refer to the Call Blocking Specific Called Numbers
Block calls based on DNIS when CUCM is using MGCP gateway
If MGCP gateway is used with the Older version of CUCM which is below 8.x the only way to block unwanted calls is based on the DNIS information. This is accomplished through translation patterns in the Cisco CallManager configuration.
An Translation pattern in CUCM must be created to match the inbound DNIS information (called party number). Then, the gateway in Cisco CallManager must be configured to have a Content Services Switch (CSS) with access to this Translation pattern first, based on the Translation pattern partition. Give the Translation pattern a CSS that has access to NOTHING. This sends the call nowhere, and the calling party receives a reorder tone.
Note: This method of blocking calls can only be accomplished based on the DNIS information (called party number) and not on the ANI (calling party number) information.
To block calls in the same manner at the Cisco CallManager level, use translation patterns. To do this, the DNIS or called number can be specified in a route pattern, then applied to the gateway. In this case, the "****" that is used to block the call is the Route or Block this pattern option.
Note: This can only block unwanted calls based on DNIS information and not on the ANI information.