calculation of voice codec

convenientstore

can someone tell me how this works out to 8 kbps? This is from Cvoice book from ciscopress.. Just don't understand how they arrive at 8 kbps

The G.729 codec using two 10-ms samples consumes 20 bytes per frame, which works out to 8 kbps.

mikej412

Check Voice Over IP - Per Call Bandwidth Consumption

I think you're looking for this formula:
codec bit rate = codec sample size / codec sample interval
remember your 8 bits per byte and puzzle out the "common units conversion" of ms to seconds

Are you using the new CVOICE Exam Certification Guide?

I remember a good explaination somewhere in the "old books" -- not sure about those new-fangled updated books that hint at the exams in the titles