This article presents the two approaches usually chosen in order to obtain Quality of Service (QoS) in active networks. The first one we call "active approach" allows to define protocols (or services) adapted to flows contents (in particular their semantics) but does not permit to set priorities to flows. The second one uses QoS provided by IP network layer (under active networks). Weakness of this latter approach is then identified: while it simplifies the implementation of QoS in active networks, the obtained QoS is almost as flexible as service offered by IP layer. In this article, we propose a new approach where QoS is managed at "active network" layer rather than at IP layer. This new approach is far more flexible and allows us to provide QoS mechanisms not limited by those at IP layer. We show that our solution offers QoS with a better granularity: packet-grained rather than flow-grained. We have performed many experiments that validate this flexible approach of QoS at active network layer in particular on the high-speed active node Tamanoir.