[OSC_dev] zeroconf, namespace querying

[Andy W. Schmeder]

On Feb 24, 2008, at 1:14 PM, Stephen Sinclair wrote:

> - The 2006 meeting minutes suggest using simply the address with a '/'
> appended: http://opensoundcontrol.org/publication/nime-2006-osc- 
> developers-meeting

The simplicity of this approach seems to be popular and it would  
probably work in many cases.

However there is a caveat to putting *any* sort of query system into  
OSC itself because it is not compatible with the isochronous  
transport.  (Oops!)

I personally favor an XML descriptor approach e.g. WSDL or the D-Bus  
introspection format.


> Also, Steve Harris suggests that we should use mDNS records to
> announce more than just '_udp._osc', but include some descriptive
> fields such as a URI with information on the service.

There is a natural mapping from these mDNS TXT attributes to IANA  
type options.

OSC doesn't have a registered IANA type (for now I've used x- 
application/osc), but I am working on the application.

So far I've identified three attributes that I think are useful:

version=1.0 			(or some later number, when available)
framing=slip 			(attribute used for serial transports making use of  
the SLIP RFC1055 framing mechanism)
schema=http://.....		(any URI)

The schema URI is chosen to uniquely identify the device.  e.g.  
http://opensoundcontrol.org/implemenation/thingxyz#version-0.1.  (It  
does not have to be opensoundcontrol.org nor even necessarily http --  
it could also be file:, ftp: etc)

At some future point it might also return a service descriptor, so it  
leaves that possibility for future development.



---

Andy W. Schmeder
andy [at] cnmat.berkeley.edu
phone:	+1-510-643-9990 x.313

Programmer/Analyst II
Center for New Music and Audio Technologies
University of California at Berkeley
http://cnmat.berkeley.edu

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.create.ucsb.edu/pipermail/osc_dev/attachments/20080224/d482ff9a/attachment.html