RE: xAP to UPnP connector

["Edward Pearson" <edward.mailgroup@xxxxxxxxxxxxxxxx>]

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Functionally, there is a significant overlap between uPnP and xAP. The key
difference is the entry level for a device to be a node on the network. xAP
has defined transmission level protocols for serial and IP networks. The
only protocol a device needs to be a xAP node on an IP network is UDP. To
implement uPnP, it needs UDP, TCP, HTTP with multicast addressing and
optionally DHCP and DNS. There's a lot of code a node needs to implement
before it is useful, eg the discovery protocol alone is a challenging thing
to implement. That's fine for a commercial organisation to justify but
unattractive to a hobbyist who wants to get on and do useful stuff. Nodes
need to be able to process complex XML messages.  So very simple embeded
devices (eg PIC-based) are effectively excluded. In time, ultra-cheap
hardware with these capabilities will become available. But in the 5 years
since uPnP was first defined, it hasn't so implementations have remained
only for pretty capable hardware (PC's, printers, routers) and not for
lightswitches, motion detectors etc.

The uPnP audio architecture, while incomplete, is well thought out and
shows
promise. And audio servers and players (renderers) mostly now (just) have
enough capability to implement it. What audio device do you have that talks
uPnP? I think that Telcanto may have done some work in this area. Is
Malcolm
on this list or only on the developers list?

_____

From: Jeremy Laurenson [mailto:jeremy@xxxxxxx]
Sent: 12 February 2005 02:15
To: xap_automation@xxxxxxx
Subject: [xap_automation] xAP to UPnP connector


Hi all,

It seems to me these are somewhat competing technologies, but I have some
audio stuff thats controllable via UPnP...

Any way to get upnp onto xap?