Voice Translation Rules 101
Voice Gateways / September 14, 2011

In my opinion, voice translation rules are one of the most powerful tools available with the H.323 feature set on IOS. This also includes CME since it is basically an H.323 gateway with some additional functionality. With the voice translation rules, you can do away with the need for num-expansion and also with CME you don’t need to use the potentially problematic dialplan-pattern. What I will do for the purposes of this document is to present some of the most common scenarios for translation rule usage and how they apply. Translating 10-Digit DID to 4-Digit Extension Probably one of the most common uses of translation-rules is taking a 10-digit DID number coming from the PSTN and breaking it down into a 4-digit extension. For our purposes, the DID coming into the system is 214-555-3XXX and the extension is 3XXX. Here’s what you will need to do for this task: voice translation-rule 1 rule 1 /^214555\(3…\)$/ /\1/ Ok, let’s stop there for a second and cover what we have just entered. The first line just states that you are starting a translation-rule and the tag for that rule is 1. That 1 has no relation to the 1 in the second…