Re: [linux-audio-dev] OSC, mDNS and LASH: a good combo?

Hi everyone,

        Just a quick note on discovery from the RTP MIDI
experience:

http://www.cs.berkeley.edu/~lazzaro/rtpmidi/index.html

        The assumption we're making is that existing IETF
session management tools -- the Real Time Streaming
Protocol (RTSP) for applications that feel like content
distribution, and the Session Initiation Protocol (SIP) for
applications that feel like telephony -- will be the way
RTP MIDI (together with audio and video and text, etc)
sessions will get set up, and that the mechanisms these
tools use for discovery will be used for RTP MIDI.

        On SIPPING (the place where new SIP frameworks
are born and raised):

http://www.ietf.org/html.charters/sipping-charter.html

there has been a lot of activity recently about
"p2p SIP architectures", which in a LAN context is the
sort of discovery people are talking about here (link-local
multicast, the backbone of mDNS, is the LAN tool at the
bottom). But there's also an interest in making these
p2p SIP architectures work outside a LAN context, which
is where the "p2p" comes from -- they look for inspiration
from the file-sharing world for discovery (Distributed Hash
Tables, etc) ...

Also, note that basic SIP already has some link-local
multicast support -- a new phone coming on line can
sent a REGISTER to a well-known local multicast address
and port, where any SIP proxies online will be listening.
This doesn't solve the bigger question of how you make
an architecture where even phone is also a SIP proxy,
and act to serve each other ... which is what the SIPPING
work is about.

---
John Lazzaro
http://www.cs.berkeley.edu/~lazzaro
lazzaro [at] cs [dot] berkeley [dot] edu
---