We are a partnering with a carrier to ready networks for implementing VoIP. I understand the carrier implements QoS on their Router at the demarcation point at client site. That is where they stop and we begin. We are planning on implementing a VLAN for phone traffic. My question is this: At what point is it necessary to implement QoS INSIDE the network architechture (other than the router going out to the world)? We are working with small to medium businesses, 30-175 users.
It was recommended that this would be of little benefit to the customer considering the time and cost to implement QoS. I just want to confirm this from a professional.