15:06:59 RRSAgent has joined #wot-di 15:06:59 logging to http://www.w3.org/2015/07/01-wot-di-irc 15:07:08 rrsagent, set logs public 15:07:36 helena has joined #wot-di 15:09:38 present+ DanhLePhuoc 15:10:27 https://filesender.heanet.ie/1.6/?vid=0b60067c-e7bd-c629-bacf-00005974b1bb, the link to the presentation 15:10:40 scribenick: dsr 15:10:50 meeting: Wot Discovery Task Force 15:11:22 Dahn presents Thing Discover on the Graph of Things see link above 15:11:33 s/Dahn/Danh/ 15:12:19 Danh: I try to share my demo 15:12:51 Screen shows world map with heat map and locations as overlay 15:13:00 chair: Dave 15:13:33 Present+ Dave, Danh, Ashok Helena, Joerg 15:13:41 Regrets: Soumya 15:14:28 Danh shows how you can browse the data screens using some JavaScript effects 15:14:59 At the bottom there is a live display of data courtesy of a web socket connection with the server. 15:16:02 He returns to the slide presentation 15:16:52 We use HTTP content negotiation as a discovery mechanism, along with a sparql query. 15:17:38 The query results are returned in JSON 15:18:17 We’re using an RDF graph for the data models 15:19:21 There are plenty of ontologies available. 15:19:33 We also have RDF linked data streams 15:19:55 Static knowledge is treated as background knowledge 15:20:53 The sensor metadata describes the stream, with sparql 1.1 specification 15:21:47 We had to extend the sparql query language slightly to be able to aggregate data over a given time period 15:23:08 This also allows you to query the data at a specific time (in the past) 15:23:53 You can define a query that returns a stream for data that satisfies that query 15:26:28 Slide with stats on amount of data, cluster of servers and the software libraries 15:27:11 People ask if you can make it smaller? Yes through smart gateway 15:28:12 We’re working on making it work on Android and Raspberry Pi 15:28:30 The code foot print is in range 4-8 MB. 15:28:45 Memory foot print in range 4 - 64MB 15:29:15 Plenty of room for further improvementsto make it smaller faster and more scalable 15:29:55 Danh finishes 15:30:09 Dave: questions anybody? 15:31:01 Joerg: this looks like a complete solution inspired from sensor networks. We now need to identify some potential building blocks in respect to discovery, any suggestions? 15:31:30 Danh: we only use REST API, complexity is determined by the nature of the query 15:32:09 A few years ago we implemented a small query engine for simple queries 15:32:31 Joerg: in the task force we discussed different notions of discovery 15:33:19 Your presentation is about discovery of certain resource with a particular characteristic. 15:33:30 Dahn: yes, here we focus on data discovery 15:33:45 First you need to discovery the sparql endpoint 15:34:32 The linked data community has ideas for how to query endpoints for their metadata, e.g. their capabilities 15:35:43 We’ve looked at using JSON for queries as an alternative to sparql for restricted classes of queries 15:35:55 Dave: any other questions? 15:36:35 Helena: I want to understand continuuous discovery, is there an anouncement for sensors? 15:37:16 Danh: you first need to discover the query end point, and can then query for all sensors satisfying some constrain. 15:37:31 Helena: the sensors have to register with the system in some way? 15:37:36 Danh: yes 15:39:03 Dave: this is like the Compose project where queries for event streams from a set of sensors is a live query, i.e. reflects the sensors currently registered 15:39:47 Danh: one point - this approach doesn’t have to run on the public Internet. 15:40:50 Topic: Technology Landscape for Discovery 15:44:18 Joerg: what are the steps in discovery with links to use cases, and then look at dependencies on work in othe task forces. 15:45:34 You have already listed some mechanisms for discovery, and should now add examples, and the relationship to thing descriptions, APIs and to security, privacy etc. 15:46:23 Dave asks for contributions for next week’s call 15:46:45 Joerg: yes we should invite contributions for the landscape analysis along with links 15:47:42 Dave: I could offer to provide an overview of the Compose system approach to discovery. 15:48:14 Joerg: yes, but you should break it down into the components/building blocks 15:49:51 present+ Hamid 15:50:13 rrsagent, make minutes 15:50:13 I have made the request to generate http://www.w3.org/2015/07/01-wot-di-minutes.html dsr