Better applications require enhanced networking, specially in highly demanding applications such as in the case of modern Ambient Intelligence (AmI). Unfortunatelly the network is there and should make the most possible so that not be a barrier. A new Network Enhancement concept is proposed, defined as the action and effect of enhancing the network. This approach may be useful to set specific enhancement objectives and to make sure that the final effect in the network is achieved. In this paper, the Network Enhancement concept is described, and the Virtual Quality-of-service Network (VQN) model is presented as an example of the development of an external network enhancement tool to provide virtual QoS over an existing network.