/mcpDescription Term A call for which the call classification setting of the trunk, gateway, and route pattern gets considered. The Allow Device Override setting on the route pattern determines whether the trunk or gateway call classification setting gets used instead of the route pattern call classification setting. Outgoing Call Configure External Call Transfer Restrictions Task Flow Procedure Purpose Command or Action Block external calls from being transferred to another external device or number. Configure the Service Parameter for Call Transfer Restrictions, on page 508 Step 1 Configure gateways and trunks as OnNet (internal) or OffNet (external) by using Gateway To configure incoming calls perform the following procedures: Step 2 Configuration or Trunk Configuration or by setting a clusterwide service parameter. • Configure the Clusterwide Service Parameter, on page 509 • Configure Gateways for Call Transfer Restrictions, on page 510 • Configure Trunks for Call Transfer Restrictions, on page 510 Configure transfer capabilities with route pattern configuration. Configure Outgoing Calls, on page 511 Step 3 Configure the Service Parameter for Call Transfer Restrictions To block external calls from being transferred to another external device or number: Procedure Step 1 From the Cisco Unified CM Administration user interface choose System > Service Parameters. Step 2 On the Service Parameter Configuration window choose the Cisco Unified CM server you want to configure from the Server drop-down list. Step 3 Choose Cisco CallManager (Active) from the Service drop-down list. Step 4 Choose True from the Block OffNet to OffNet Transfer drop-down list. The default value specifies False. Step 5 Click Save. Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs 508 Receiving Calls Configure External Call Transfer Restrictions Task Flow