Subject: [SIP] Quake-over-SIP?

From: "Dialout.net (David Yon)" <[email-masked]>
Date: Fri, 21 Jul 2000 15:53:10 -0400

Is there spec/docs for how the Internet multi-player Quake support uses 
SIP?  Anyone know where I can find it?  I heard about this at VON and have 
come up empty in my web searching.

	I'm particularly interesting to see if they are using TCP-based transport 
(for the media, not SIP itself) and how they solved some of the impedance 
mismatches between SDP and TCP-based transports.

David Yon
Chief Technical Officer
Dialout.Net, Inc.
[email-masked]

_______________________________________________
SIP mailing list
[email-masked]
http://lists.bell-labs.com/mailman/listinfo/sip

---

From: Jonathan Rosenberg <[email-masked]>
Date: Sun, 23 Jul 2000 00:41:37 -0400

> come up empty in my web searching.

I asked the folks who worked on it to submit an I-D for the meeting, but
I haven't seen anything. It would be very nice to see that.

> mismatches between SDP and TCP-based transports.

SDP is not a transport, so comparing it to TCP is apples/oranges.
Apparently you can simply start quake with command line parameters that
point to a server, game name, etc. It is my understanding that they
simply passed these parameters in SDP. Something like:

m=application 3726 tcp quake
a=fmtp:quake <quake params>

would be my guess about how it was accomplished.

-Jonathan R.
-- 
Jonathan D. Rosenberg                       72 Eagle Rock Ave.
Chief Scientist                             First Floor
dynamicsoft                                 East Hanover, NJ 07936
[email-masked]                     FAX:   (973) 952-5050
http://www.cs.columbia.edu/~jdrosen         PHONE: (732) 741-7244
http://www.dynamicsoft.com

---

From: "Johan Liseborn" <[email-masked]>
Date: Mon, 24 Jul 2000 10:40:13 +0200

> I haven't seen anything. It would be very nice to see that.

Hmm, yes we had the intention of finishing the draft to this meeting,
but unfortunately there was not enough time. There *is* an early
version of a draft (and, of course, our implementation of it :-),
but I feel that it needs some more work before making it publicly
available.

> would be my guess about how it was accomplished.

Your guess is correct. This is basically how we do it. The tricky thing
is what parameters you need. There are many different games and
many different modes of the games (such as deathmatch, capture the
flag, domination, etc), where different games and modes require
different types of parameteres (such as player names, teams, maps,
etc).

Looking forward to playing Quake with everybody on the SIP list!

/johan

--
Johan Liseborn
CTO, Hotsip AB
phone: +46 (0)8 555 10 702
mobile: +46 (0)739 888 160

---

From: Henry Sinnreich <[email-masked]>
Date: Mon, 24 Jul 2000 05:57:09 -0500

Games are a fascinating new application for SIP!
Am looking forward to your draft.

Henry

>-----Original Message-----
>From: [email-masked]
>[mailto:[email-masked]]On Behalf Of
>Johan Liseborn
>Sent: Monday, July 24, 2000 3:40 AM
>To: Jonathan Rosenberg; Dialout.net (David Yon)
>Cc: [email-masked]
>Subject: Re: [SIP] Quake-over-SIP?
>
>
>> >         Is there spec/docs for how the Internet
>multi-player Quake
>support uses
>> > SIP?  Anyone know where I can find it?  I heard
>about this at VON and
>have
>> >         I'm particularly interesting to see if
>they are using TCP-based
>transport
>> > (for the media, not SIP itself) and how they
>solved some of the
>impedance

---

From: David Yon <[email-masked]>
Date: Mon, 24 Jul 2000 07:13:25 -0400

Answering both at once to reduce the traffic here...

> > simply passed these parameters in SDP. Something like:

         Well yes, my ambiguous phrasing aside, of *course* SDP is not a 
transport.  That said, SDP is not particularly well suited to *describe* a 
media transport that is TCP based.  It wants to assume a transport where no 
connection needs to be brought up, the major omission being who is the 
initiator of the connection and who should be the listener.  Forget all 
about RTP---I'm talking about a media transport which can be deployed using 
a single TCP connection between the endpoints.

>different types of parameteres (such as player names, teams, maps,

         Ok, so I assume that the two endpoints bring up a TCP connection 
in order to play the game?  If so, how does the above SDP describe which 
endpoint does the "connect" and which does the "accept"?  Is TCP a 
well-known SDP transport type?  Would an off-the-shelf SIP proxy that's 
managing a firewall/NAT know how to open up a port to let this through?

         I don't mean this as a criticism of the above approach, we will 
probably end up doing something similar.  I want to make sure that we are 
as interoperable as possible, and the prevalence of RTP/UDP transports in 
SIP networks has me concerned that an odd-duck TCP-based transport will 
cause breakage if there is no standard model to be followed.

David Yon
Chief Technical Officer
Dialout.Net, Inc.
[email-masked]