For both small and medium customers, a simple configuration is more effective than a complex configuration when implementing QoS for voice, data, signaling and video. If traffic engineering is done properly and sufficient bandwidth is available, especially for WAN links, voice and voice signaling traffic can both be tagged as DSCP 46. This Class of Service (CoS) tagging places both types of packets into the same High Priority queue with minimum of effort. The key is to have enough bandwidth to prevent any packets from dropping.

Large enterprises and multinational companies might find a stratified approach to CoS more beneficial. This approach allows maximum control for many data and voice services. For this environment, customers must use DSCP 46 (Expedited Forwarding) for voice (bearer), but voice signaling could have its own DSCP values and dedicated bandwidth. This would prevent traffic from contending with signaling. Although the configuration can be more complex to manage and administer, the granularity will give the best results and is regarded as a best practice.

For the routers, customers must use strict priority queuing for voice packets and weighted-fair queuing for data packets. Voice packets should always get priority over non-network-control data packets. This type of queuing is called Class-Based Queuing (CBQ) on Avaya data networking products or Low-Latency Queuing (LLQ) on Cisco routers.