There can be two kinds of Content Distribution Protocols: non real-time and real-time.
The File Distribution Protocol is a simple protocol for non real time content distribution.
The Overlay Streaming Distribution Protocol is a simple mesh-based streaming protocol for real time content distribution.
Both protocols were developed for PeerSim P2P network simulator at the Dipartimento di Ingegneria e Scienza dell'Informazione (DISI) of the University of Trento.
PeerSim is a Java based simulator that consists of many configurable components: it has two types of engines, cycle-based and event-driven, and different modules that manages separately, for instance, the overlay building process and the transport characteristics. For a more detailed description of PeerSim simulator please refer to this page.
Both protocols can build tree- and mesh-based architectures and can be easily configured to obtain different scenarios: by properly adjusting the input parameters it is possible to obtain networks with 103-105 nodes, with different constraints on minimum and maximum outdegree.
D. Carra, R. Lo Cigno, E.W. Biersack, "Stochastic Graph Processes for Performance Evaluation of Content Delivery Applications in Overlay Networks", in IEEE Transactions on Parallel and Distributed Systems, Vol. 19, No. 2, pp. 247-261, Feb. 2008
D. Carra, R. Lo Cigno, E.W. Biersack, "Graph Based Modeling of P2P Streaming Systems", IEEE Journal on Selected Area in Communications (JSAC), Vol. 25, No. 9, pp. 1667-1677, Dec. 2007