Supporting the OSGi Service Platform with Mobility and Service Distribution in Ubiquitous Home Environments

The OSGi service specification defines an open service platform for service delivery, composition and execution in networked environments. The specification, however, is limited to a single java virtual machine (JVM) and does not define the distribution and mobility of services across different OSGi platforms and devices. This paper first revisits the fundamentals of OSGi service distribution, clarifies and defines a terminology for OSGi service mobility and distribution. It then proposes to extend the current OSGi platform with service distribution and service mobility that aim to support three important requirements on ubiquitous applications, namely, spontaneous interoperability, mobility and software adaptability. The paper demonstrates these extensions through several prototype implementations. These extensions are supported through a common framework, which targets at ubiquitous environments and aims to facilitate the construction of OSGi applications that span multiple OSGi platforms, multiple JVMs and multiple devices. In addition, the proposed framework offers two special features: First, it supports automatic contextual management through a virtual global shared space whose content is automatically and dynamically adjusted to reflect the changes in the system and the mobile environment; Second, it supports different OSGi bundle and service mobility paradigms. The proposed framework blurs the distinction between local and remote services, where remote services can be accessed as if they were local, which greatly simplifies application development. We believe existing OSGi platform distribution solutions can also be supported by this framework.