LOD Laundromat Tutorial
@ KR on the Web

April 29th, 2016

Wouter Beek

How much time was there between the possibility of the WWW and the WWW?

  • 1963, Hypertext, Ted Nelson
  • 1968, Videoconferencing, Douglas Engelbracht
  • 1969, Large-scale networks, ARPANET
  • 1991, The first Web site goes online, TBL

How much time will there be between the possibility of the SW and the SW?

Why does not everybody use the SW all day long today?

Metcalfe's Law

The value of a network is proportional to the square of the number of connected nodes

So... how many connected nodes does the SW have?


SW nodes have low availability

SW nodes enforce restrictions

SW nodes are not tightly connected

Data growth is exponential

SW growth is linear


[Why1] Allocative Efficiency

What the consumer is willing to pay should equal the marginal cost of production

[Why2] Multi-tenancy

Difficult in a decentralized deployment

Mostly a social challenge

SW layer cake

SW publishers have to set this up locally

SW innovation on one slide

< ... >

{ ... }

After the first 15 years of SW deployment most data cannot be automatically...

  • found
  • read
  • queried
  • reasoned over

LOD Laundromat

Beek & Rietveld & Bazoobandi & Wielemaker & Schlobach “LOD laundromat: A Uniform Way of Publishing Other People’s Dirty Data” ISWC 2014
Rietveld & Verborgh & Beek & Vander Sande & Schlobach, “Linked Data-as-a-Service: The Semantic Web Redeployed” ESWC 2015

LOD Laundromat Layer Cake

Beek & Rietveld & Schlobach & Van Harmelen “LOD Laundromat: Why the Semantic Web Needs Centralization (Even If We Don't Like It)” IEEE Internet Computing 20 (2) p.78-81, 2016

[1] Find IRIs



Ilievski & Beek & Van Erp & Rietveld & Schlobach “LOTUS: Adaptive Text Search for Big Linked Data” ESWC 2016

[2] Find statements



W. Beek & L. Rietveld. “Frank: The LOD Cloud at your Fingertips” Extended Semantic Web Conference: Developers Workshop, 2015.

./frank statements -s http://dbpedia.org/resource/Monkey -g

[3] Find documents


./frank documents --namespace http://www.w3.org/2006/vcard/ns# | ./frank statements

./frank documents --minTriples 880 --maxTriples 900 -d

[4] Scale your LOD evaluation


Rietveld & Beek & Schlobach “LOD Lab: Experiments at LOD Scale” International Semantic Web Conference 2015 (Best Paper Award)

./frank statements -p foaf:knows | grep last-fm > last-fm.nt