Room 4 

10:20 - 11:20 


Talk (60 min)

Offline first computing in an online world

Conflict-free Replicated Data Types (CRDT for acronym afficiandos) are data structures that can be used to build offline first systems - think git. Programs built on top of CRDTs primarily work on a local copy of the world, and then have some mechanism to synchronize their state with other participants in the system. Data Distribution Service (DDS) is one of many publish-subscribe systems in existence. It differs from most in that it is a standard (so there are many implementations) and in that it is broker-less (so there is no server). The lack of a central message broker is of particular interest, because it means that it works on infrastructure with no servers. This talk will give a short introduction to DDS and CRDT technologies and then look at how they can be combined to create truly distributed applications. CRDTs allow for complex distributed state, while DDS provides near real-time updates. Having both at the same time makes it possible to build a wide range of applications. The presentation will also touch upon some of the broader ideas underlying such systems, and aims to be of interest to developers that are merely offline-curious. The presentation will include a demo.

Ørnulf Staff

Ørnulf Staff works at Kongsberg Defence and Aerospace. His area of expertise is data distribution in environments where catastrophic failures are to be expected. He is lead developer on Kongsberg's in-house implementation of the DDS standard called InterCOM DDS. The library is widely used in both civilian and military parts of the company.

Ørnulf has a PhD in distributed numerical algorithms from the University of Oslo. He has worked as a developer at Kongsberg for the past 13 years, first with flow simulation at the oil and gas division (now Kongsberg Digital). He has been at Kongsberg Defence and Aerospace since 2015.