Re: [WotT IG] Architecture draft

Please see the inline comments.

Best Regards,

--- Jonathan Jeon
전종홍 드림

2015. 4. 27. 10:07 <Kerry.Taylor@csiro.au<mailto:Kerry.Taylor@csiro.au>> <Kerry.Taylor@csiro.au<mailto:Kerry.Taylor@csiro.au>> 작성:

Dear WoT-ers

http://hollobit.github.io/swot-model/


I have just had a look at this architecture.

I think there should be a much clearer differentiation between “WoT devices” and “WoT Servers” .
Obviously we would want to enable that a  Thing that is a “WoT device” could  also  host a “WoT server” but the two  should be firmly distinguished
(with, possibly, some attention to a special  low-cost internal interface between a co-hosted server and device that does not assume an Ethernet or wireless connection. But as this capability would be internal to  an implementation it does not really need to be standardised).

I have updated some definitions about WoT server, WoT device and others.
Please review this document and wiki page again.
https://www.w3.org/WoT/IG/wiki/Terminology



The concept of a “WoT Device” (that necessarily includes a “Wot Server”) plus “other WoT Devices” is inelegant and confusing.  Surely those “other WoT Devices” would also have “Sensors”  and should conform to the WOT-3 interface if possible, or otherwise make their internal sensors visible through WoT-4 without having to also offer WOT-1 and Wot-2?

WoT-4 just means the interaction interface between WoT devices (as Things). If other WoT device have sensors, they also have aonther WoT-3 interface for sensor. It's similar with a recursive model.

The reason is that we should expect a server, which deals with  distant device interaction, to be considerably more capable and to have (nearly) always-on connectivity.  There are many existing high end devices that manage multiple sensors and maybe even speak wifi, but  that will never deliver WoT server functionality.  I guess this is almost consistent with the proposed architecture anyway---perhaps I am seeking a conceptual re-factorisation rather than anything technically different.

I don't think that every WoT device should embed a WoT server because there are various device types and capabilities. So I'm trying to classify the WoT device level and its expected functionality.


Also, note the  widely used Semantic Sensor Network vocabulary  (on track for  Recommendation in the Spatial Data on the Web Working Group)  models “Sensing Devices” as both “sensors” and “devices” (allowing inheritance of characteristics from both ) -- it would make sense to me for this WoTgroup to aim  fill in more about the device capabilities that is needed for this WoT role.

Kerry (co-chair of W3C + OGC SDWWG)




Dr Kerry Taylor
Principal  Research Scientist
Digital Productivity, CSIRO
Adjunct Professor, ANU; Principal Fellow, University of  Melbourne; Visiting Reader, University of Surrey, UK