The current industry trend of convergence between computing and networking eco-systems clearly shows that software will play an unprecedented dominant role also in future communication environments. Computing, storage, and connectivity services, as well as any other present and future application instances, will be deployed in the form of virtualized assets within a software-defined infrastructure running on top of general-purpose processing and communication hardware, all managed and made available under the cloud "As A Service" paradigm. This technological convergence and infrastructure sharing between the computing and communication systems portend a scenario with a "fog" of micro-clouds composed of generalized virtual functions providing both applications and network services that supplement those deployed in traditional cloud datacenters.

The Second IEEE Workshop on Orchestration for Software-Defined Infrastructures (O4SDI) addresses the challenges that will facilitate orchestration and programmability of generalized virtual functions in Software Defined Infrastructures (SDI), enabling cloud and network providers to deploy integrated services across different resource domains. Orchestration mechanisms will facilitate the live deployment and lifecycle management of these virtual elements, at the application level, the server level, and the network level within a single domain and across multiple domains. Without such orchestration it will not be possible to enable dynamic establishment of generalized virtual functions chains, according to service requirements.