[discovery] and [sensors]: Webinos high level service discovery API and sensor API

Hi,



We have seen very interesting inputs from Rich on Local-Network and Wide-Area Network Service Discovery and Interaction [1] and [2]. Related to this I take the opportunity to share some results of the API specification phase of the Webinos EU-project, http://webinos.org/ as this is very appropriate for the work within DAP.



In Webinos a set of APIs have been specified, http://dev.webinos.org/specifications/draft/.



Among these APIs there is a high level service discovery API and a generic sensor API. Note that these are drafts and will be evaluated during the implementation of the Webinos platform.



A short description of these two APIs follows:



The Discovery Module (http://dev.webinos.org/specifications/draft/servicediscovery.html):



- Provides web applications with an API to discover local and remote services without any previous knowledge of the service.



- A discovered service is accessed through binding to a "standard" API. For example, access to a geolocation service in another device is performed through binding the W3C Geolocation API to the selected remote geolocation service.



- The API is high level and agnostic to underlying low level discovery and communication mechanisms



The Sensors Module (http://dev.webinos.org/specifications/draft/sensors.html):



- Provides web applications with an API to access data from sensors in the device, connected to the device or in another device.



- The API is agnostic to underlying low level methods for sensor discovery and communication with sensors and should be used in combination with Webinos service discovery.



- A DOM event provides sensor data similar to the DeviceOrientation and Battery event specifications.



Comparing the Webinos Discovery Module with the Local-Network Service Messaging API proposal [1] by Rich we have the following differences:



- Rich's proposal uses messaging (XHR, Web Sockets, Server-sent events, Web Messaging) to communicate with selected service, while Webinos uses JS binding to a well defined JS API and hides underlying communication mechanisms.

- Rich's proposal builds the service selection mechanism and call backs when the user has selected the service, while Webinos has a callback for each discovered service and the application developer has to build the selection mechanism.

- Rich's proposal is limited to services in local networks, while Webinos enables both local and remote services. (but Rich address wide area networks in [2]).

- Webinos allows newly installed APIs to be exposed and discoverable.

- Webinos is higher level than Rich's. Could an implementation of Webinos Service Discovery uses Rich's proposal as underlying solution?



Comments are welcome.



Best regards

  Claes





[1] http://lists.w3.org/Archives/Public/public-device-apis/2011Jul/0073.html

[2] http://lists.w3.org/Archives/Public/public-device-apis/2011Aug/0018.html



[cid:image001.gif@01CC5CF2.2E832750]

Claes Nilsson M.Sc.E.E
Senior Technology Strategist
Technology & Research - Advanced Application Lab

Sony Ericsson Mobile Communications
 Phone:  +46 10 80 15178
Mobile: +46 705 56 68 78
Switchboard: +46 10 80 00000
E-Mail: mailto:claes1.nilsson@sonyericsson.com
Visiting Address; Nya Vattentornet
SE-221 88 LUND,
Sweden
Disclaimer:
The information in this e-mail is confidential and may be legally privileged. It is intended solely for the named recipient(s) and access to this e-mail by anyone else is unauthorized. The views are those of the sender and not necessarily the views of Sony Ericsson and Sony Ericsson accepts no responsibility or liability whatsoever or howsoever arising in connection with this e-mail.Any attachment(s) to this message has been checked for viruses, but please rely on your own virus checker and procedures. If you contact us by e-mail, we will store your name and address to facilitate communications. If you are not the intended recipient, please inform the sender by replying this transmission and delete the e-mail and any copies of it without disclosing it.