What is a translation pattern?

• A. A pattern that matches dialed digits and routes to a gateway.
• B. A pattern that matches dialed digits and transforms them without consuming a gateway.
• C. A pattern that records digits for billing.
• D. A pattern that blocks invalid digits.

Answer: (B)

Translation patterns modify how a dialed number is interpreted rather than choosing a gateway directly. They define a pattern to match digits someone dials and then transform that matched portion into a different digit string that the routing system will use to find the next hop. The key idea is digit transformation applied during call setup, without automatically steering the call to a gateway—the transformed number is then subjected to the usual route logic, which may still route through a gateway if appropriate.

This makes translation patterns handy for changing prefixes, normalizing numbers across trunks, or adapting dialed strings to the format the destination expects.

Why the other ideas don’t fit: routing to a gateway is handled by route patterns, not translation patterns. Recording digits for billing is a separate feature, and blocking invalid digits is not the primary role of a translation pattern, which centers on transforming digits for routing.