Section: New Results

Convergence middleware for pervasive data

Participants : Yoann Maurel, Jules Desjardin, Paul Couderc [contact] .

We are currently working on data driven middleware approaches dedicated to physical objects and smart spaces. We had previous contributions on the topic, where opportunistic collaborations between mobile devices were supported by Linda-like tuple space and IEEE 802.11 radios. However, these were adapted to relatively complex devices and the technological limitation at the time did not allow the full potential of the model. More recently, we investigated distributed storage spread over physical objects or fragments using RFID, enabling complex data to be directly reflected by passive objects (without energy). Yet other radio technologies, such as BLE, are emerging to support close range interactions with very low (or even zero) energy requirements.

Applications such as pervasive games (for ex. Pokemon Go), on the go data sharing, collaborative mobile app are often good candidates for opportunistic or dynamic interaction models. But they are not well supported by existing communication stacks, especially in context involving multiple technologies. Technological heterogeneity is not hidden, and high level properties associated with the interactions, such as proximity/range, or mobility-related parameters (speed, discovery latency) have to be addressed in an ad hoc manner. We think that a good way to solve these issues is to offer an abstract interaction model that could be mapped over the common proximity communication technologies, in a similar way as MOM (Message Oriented Middleware) such as MQTT abstract communications in many IoT and pervasive computing scenarios. However, they typically requires IP level communication, which far beyond the capabilities of ultra low energy proximity communication such as RFID and BLE. Moreover, they often rely on a coordinator node that is not adapted in highly dynamic context involving ephemeral communications and mobile nodes.

We started the implementation of an associative memory mechanism over BLE, as it is a common ground that can be shared with passive or semi passive communications (RFID, NFC). Such mechanism, although relatively low level, is still a very useful building block for opportunistic applications: it enables opportunistic data storage/sharing and signaling/synchronization (in space in particular). This approach is fully in line with more general trend developed in the team to build "smart" systems leveraging local resources and data oriented mediation.  We have started validation work with a few applications, in particular regarding energy aspects and scalability with respect to the communication load. This should lead to publishing on both infrastructure and application level aspects of the approach.