1. A peer-to-peer network system, comprising: a plurality of peer nodes coupled to a network; a class of software module provided by one or more of the peer nodes; a module class advertisement for the class of software module that defines a local behavior and an Application Programming Interface (API) for each of one or more peer-to-peer bindings that supports the class of software module, wherein the module class advertisement includes a module class identifier that uniquely identifies the class of software module; and one or more module specification identifiers that each uniquely identifies one of one or more module specifications of the class of software module, wherein each module specification includes an indication of an expected on-wire behavior and one or more network protocols for a particular embodiment of the class of software module.