  This paper aims to provide insight into stability of collaboration choices in
P2P networks. We study networks where exchanges between nodes are driven by the
desire to receive the best service available. This is the case for most
existing P2P networks. We explore an evolution model derived from stable
roommates theory that accounts for heterogeneity between nodes. We show that
most P2P applications can be modeled using stable matching theory. This is the
case whenever preference lists can be deduced from the exchange policy. In many
cases, the preferences lists are characterized by an interesting acyclic
property. We show that P2P networks with acyclic preferences possess a unique
stable state with good convergence properties.
