HANOI, Vietnam Oct. 26, 2018 /PRNewswire/ — Viettel’s real time billing system (vOCS 3.0) was awarded the Gold Stevie Award for “Best New Product or Service of the Year” entry at the International Business Stevie Awards held in London England on October 21 st , 2018 by the time zone of Vietnam. Viettel vOCS 3.