摘要 : Opportunistic Mobile Networks (OMNs) enable communication among the otherwise disconnected devices via intermittent contacts. Based on this premise, the paradigms of Opportunistic Computing (OC) and Opportunistic Service Provision... 展开 Opportunistic Mobile Networks (OMNs) enable communication among the otherwise disconnected devices via intermittent contacts. Based on this premise, the paradigms of Opportunistic Computing (OC) and Opportunistic Service Provisioning (OSP) were proposed, where a user can request remotely available hardware and software services from the relevant nodes that are not in direct contact with the user’s device. In this work, we consider the problem of OSP together with <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ordered chaining</italic>. Chaining (or composition) refers to the scenario where two or more services must be availed by a given data object one after the another, for example, translating a text file and converting it to another format. Such a chaining is termed as ordered when the required services must be availed in a specific sequence. We discuss four schemes for achieving OSP with ordered chaining. One of the proposed schemes unicasts the OSP request messages, while another one adapts a popular unicasting algorithm for OMNs. The third scheme is based on flooding, whereas in the final one, nodes replicate requests only to those who provide the concerned services. The results of performance evaluation using real-life traces and synthetic mobility models show that up to about 99 percent of the service requests can be satisfied. The results also indicate that unicasting is rather unsuitable to achieve OSP. 收起