A collaboration engineer is implementing toll fraud prevention on Cisco Unity Connection. The engineer wants to block calls to 9005551234 for any caller that reaches the Caller System Transfer conversation. Which configuration accomplishes this goal?

The "Caller System Transfer" conversation in Cisco Unity Connection allows an external caller to be transferred to a number dialed by them. This feature is controlled by a Transfer Restriction Table, not an Outdial Restriction Table. To implement effective toll fraud prevention, it is best practice to block entire categories of high-risk numbers, such as premium-rate (900) numbers, by blocking the prefix pattern. Blocking only the single number 9005551234 would leave all other 900-numbers vulnerable. Therefore, blocking the 900 pattern on the default transfer restriction table is the correct and most secure method to accomplish the goal.

A. Blocking a single, specific number is an inefficient and incomplete method for toll fraud prevention, as it fails to block other premium-rate numbers within the same 900 prefix.
B. The Default Outdial Restriction Table applies to user-initiated outdials (e.g., via voice commands) or message notifications, not to system transfers initiated by an external caller.
D. This option incorrectly uses the Default Outdial Restriction Table. The Caller System Transfer feature is governed by a Transfer Restriction Table.

1. Cisco Unity Connection System Administration Guide, Release 12.x, "Managing Restriction Tables in Cisco Unity Connection" section: This guide explains that "Restriction tables are used to control which phone numbers users and outside callers can transfer to...". It clarifies that system call handlers (like the one for Caller System Transfer) use these tables to govern transfers. The guide also notes that tables are configured with number patterns. (Reference: Chapter on "Telephony Integrations").

2. Security Guide for Cisco Unity Connection, Release 12.x, "Preventing Toll Fraud" chapter: This document explicitly identifies "System transfers" as a potential avenue for toll fraud. It recommends to "Configure restriction tables to prevent transfers and outcalls to unauthorized numbers, for example, external, long-distance, and international numbers." This supports using restriction tables to block patterns like 900 for security. (Reference: Section "Securing Cisco Unity Connection Against Toll Fraud").

3. Cisco Unity Connection Call Handler Administration, "Default System Transfer Call Handler": Official documentation on configuring call handlers specifies that the transfer capabilities of the "Default System Transfer" handler are governed by the assigned "Restriction Table for Out-of-Hours/Standard Transfers," which by default is the "Default Transfer" table. This confirms that a transfer restriction table, not an outdial one, is the correct mechanism to configure.