IRC log of wot-di on 2015-07-01

Timestamps are in UTC.

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