LOD2 Alignment

== Introduction ==
At Thursday morning January 16, we discussed at the Freshheads office in Tilburg, how we can setup PiLOD Data Platform. 
This platform supports activities with open, linked and big data and should include a playground for research, development and testing purposes among other functionalities. See the next overview with clusters of functionalities, formats and tools (in Dutch) as we discussed on Thursday.
 
Figure 1: PiLOD Data Platform Overview (source: Freshheads)
A second overview we produced on Thursday was a Front End - Back End schema (in Dutch), which is another view on this topic looking at the different data sources, the required functionalitities of the platform to support full data cycles and what applications developers would like to create in the Frond End.
Figure 2: PiLOD Data Platform Schema (source: Gerard Persoon)
For the linked data part we have in our community experience with Google Refine, D2R, Topbraid Composer, Allegrograph, Virtuoso, Silk and other tools and we are looking for ways to broaden and deepen our “LOD literacy” with the experiences that are available in other data communities.
One way of doing that is to look at the LOD2 Stack and the EUCLID deliverables. Both are projects that are executed within the EU-context that have LOD tooling and training material available that we could use for our purpose. The current overlap in the tooling we use is small, but that could change.
Figure 3: PiLOD Data Platform LOD2 Stack Overlap (source: Pieter van Everdingen)
We have also noticed that our developers and big data experts have additional tooling requirements for our PiLOD Data Platform that might not be covered by the LOD2 Stack. At all times we must have the freedom to investigate new tools and to add developer of Big Data tools in our environment.
== LOD2 Alignment ==
In this article I, --Pieter will give my personal view on a possible scenario within PiLOD to use our own experience and preferences and combine that in a pragmatic and feasible way with LOD2 and EUCLID experiences and materials. It is a phased approach that spreads its activities among three stages.
It distinguishes between three LOD2 adoption variants:
* LOD2 Lite
* LOD2 Medium
* LOD2 "Full"
You can see this as a kind of maturity model to decide at what level an EU-country has adopted the LOD2 Stack and the activities within its data cycle. In the following text I will describe the three stages on more detail including suggestions on hosting and education for the participants involved.
=== Stage 1 – LOD2 Lite ===
The first stage is 9 months in duration. We will use this stage to determine the minimal stack of LOD2 tools we would like to use for our purpose and create a targeted education program to get 20+ persons involved to learn the basics to a point that they use it in our own PiLOD Data Platform after 9 months.
Figure 4: Stage 1 - LOD2 Lite Adoption (source: Pieter van Everdingen)
During this stage we will have two environments in parallel. One local PiLOD environment with the old tools we are familiar with, that we can continue our PiLOD activities as scheduled for this year and a central EU LOD2 environment where people can learn how to work the new LOD2 tooling.
It has our preference to have a central EU LOD2 environment to start with that we can learn and practice in a stable environment with the latest versions of the tooling and don’t have the administrative burden to start with, with many new tools. But after 9 months we should be able to do it ourselves for this part.
=== Stage 2 – LOD2 Medium ===
The second stage is 6 months in duration. At this point we can create a local LOD2 environment with ‘certified’ administrators and users that we can start using the LOD2 tooling on a larger scale and do the required knowledge transfer in our community to have more people trained in the LOD2 tooling.
Figure 5: Stage 2 - LOD2 Medium Adoption (source: Pieter van Everdingen)
Also at this point we can decide, or preferably before this stage begins, what other LOD2 tools we would like to use within the LOD2 variant. Also for these new tools we could start in a central EU environment and then after 6 months incorporate new LOD2 tools in our own local PiLOD environment.
=== Stage 3 – LOD2 “Full” ===
The 3rd stage is similar to the 2rd stage, also 6 months in duration. Before this stage starts we decide what new LOD2 tools we would like to include in this LOD2 variant. This does not mean that we have to use all LOD2 tools, but that we want to make use the other LOD2 tools that are useful for us.
Figure 6: Stage 3 - LOD2 Full Adoption (source: Pieter van Everdingen)
This can mean that there might be a number of LOD2 tools that we do not use in the Netherlands if there is no demand for them in our community. At the end of stage 3 the EU activities will be closed and all additional LOD2 tools of the LOD2 “Full” variant will be installed in our local PiLOD environment.
We must emphasize in our PiLOD community that there is no obligation to use the LOD2 tools with the exception for the people that are trained in these tools. LOD2 tools and other LOD tools can be used in parallel as long as it will not results in conflicts. But it is a likely scenario that people have less urgency to use other tools ones they become more experienced with the LOD2 Stack.
== Conclusion ==
Working this way, we have activities in parallel with local en EU-centered activities. This setup could not only apply for Dutch PiLOD participants, but also for participant from other EU countries. Given the fairly low numbers of LOD experts to start with a central education approach might be more efficient.