The second point to consider is that from each location, some calls are internal to that site and some are going to outside locations. Again, as an approximation, MyCo telecom people suggests to use a 50-50 rule (50% internal, 50% going out) for the LOs and 70-30 (70% internal, 30% going out) for the HQ and RC buildings. Given this, calculate bandwidth needed for voice traffic from each location going to other locations. The bandwidth needed for voice calls within each location is not needed because all locations must have broadband connectivity for internal communications.