From: owner-ag-tech@xxxxxxxxxxx [mailto:owner-ag-tech@xxxxxxxxxxx] On Behalf Of Fabrizio.Berdondini@xxxxxxxxxxxx
Sent: 13 May 2006 17:11
To: Andrew.Rowley@xxxxxxxxxxxxxxxx
Cc: ag-tech@xxxxxxxxxxx;
owner-ag-tech@xxxxxxxxxxx
Subject: RE: [AG-TECH] Venues
Addresses: infrastructural question, CHANGED TO: Bridging Problems
Hello Andrew,
thank
you for reply, as always clear and useful to me. The scenario you prospected to
me is right the one I was thinking about as a "workaround" to the
multicast problem. For this reason I first tried to configure a BridgeServer
onto my VenueServer machine, but as far as now I'm still having some problems.
Here
is a description of what's happening.
First
of all, the VenueServer runs onto a dual-boot (XP Pro - SUSE 10) machine,
located at an externally visible IP 213.209.222.50. I first tried to configure
server and an experimental bridge for XP, so I created, following instructions
found on AG portal, a BridgeServer.cfg file, with the following structure:
----------------------------
[BridgeServer]
name = AGserver1
location = ReS
qbexec = c:\programmi\AGtk2.4\bin\QuickBridge.exe
BRIDGESERVER = AGserver
portMin = 40000
portMax = 60000
#
VenueServer
[https://213.209.222.50:8000/VenueServer]
type = VenueServer
# Centro
Monitoraggio Pazienti
[https://213.209.222.50:8000/Venues/default]
type = Venue
------------------------------------------------
I
tried to mutually exclude the bridging of the Venue or that of the VenueServer.
In both cases, however, even if the bridge seems running, it doesn't do his
job: if 2 users connect their client to the bridged venue they are able to
switch to unicast mode choosing the bridge server, but after that each one can
see only audio/video that comes out from his machine, no audio/video from the
other. Is there something misconfigured into my .cfg?
Second
question: i tryed to connect my 2.4 client to the venue:
https://ag2server.ag.manchester.ac.uk/Venues/default
then
tried to switch to Unicast, the msgbox for let me choose a bridge raised up and
I selected:
AGSC/Manchester
but
after that I got the following error:
"Use
Unicast Error"
"Stream
Information for selected bridge not found; reverting to previous
selection"
Only
some more internal venue allowed me to use unicast with a bridge, but
connecting to it with a fellow of mine who enabled unicast too, we are unable
to get audio/video streams: each one of us seems to be the only audio/video
stream inside the venue.
As
always thank you for your support,
Faber
B.
owner-ag-tech@xxxxxxxxxxx scritti il 12/05/2006 13.40.20
> Hi,
>
> I am
not sure if it is possible to tunnel an entire venue server.
>
> What
would be useful would be to have a bridge server hosted on a
> multicast enabled network. This bridge
server would allow you to
> use the venue client in “unicast” mode.
This would make a unicast
> connection to the bridge server and then the
bridge server would
> make the multicast connection.
>
> You are
welcome to use the AGSC venue server just now to try this out (
>
https://ag2server.ag.manchester.ac.uk/Venues/default). This is an
> AGTk version 2.4 venue server, but we are
bringing an experimental
> AGTk 3.0 server on line within a week
(hopefully). All venues on
> our server are bridged, although it is worth
noting that this is
> still running as a “best efforts” server in
that we try our best to
> keep it running at all times, but don’t
guarantee that it is.
>
> If this
works out, there may be scope for adding more venues,
> although I will have to speak to my team here
to see if this is
> possible. In this case, we would need a
set of multicast addresses
> that you would want to use for the venues
anyway – we don’t have any
> spare ones to use.
>
> I don’t
think there are any specific requirements to set up
> multicast routing, but I am not an expert in
this field. I would
> guess that you need your router, and every
router between yours and
> another multicast router to be multicast
enabled. I would then
> think that each router needs to know about
the other multicast
> routers, although this may be done using a
protocol, I am not too sure.
>
> Let me
know if I can help any more,
>
> Andrew J
>
============================================
> Access Grid Support Centre,
> RSS Group,
> Manchester
Computing,
> Kilburn
Building,
> University
of Manchester,
> Oxford
Road,
> Manchester,
> M13 9PL,
> UK
> Tel: +44(0)161-275 0685
> Email: Andrew.Rowley@xxxxxxxxxxxxxxxx
>
> From: Fabrizio.Berdondini@xxxxxxxxxxxx
[mailto:Fabrizio.
> Berdondini@xxxxxxxxxxxx]
> Sent: 12 May 2006 09:08
> To: Andrew.Rowley@xxxxxxxxxxxxxxxx
> Cc: ag-tech@xxxxxxxxxxx
> Subject: RE: [AG-TECH] Venues Addresses:
infrastructural question
>
>
> Thank you very much Andrew,
> quite clear right now....
>
> And now the question is...
>
> We are studying the development of an
infrastructure for reasearch
> purposes focused on domiciliar monitoring of
patients with
> Alzheimer's desease, leaving in islands or
difficult to reach areas.
> It will be developed in collaboration with
the Italian Ministry Of
> Health and other public structures, such as
ISS (Istituto Superiore
> Sanità). We thought to base it onto the
AccessGrid infrastructure.
> Thus we would need to have a couple of
VenueServers connected to the
> Mbone in order to provide connectivity via
Multicast for each
> videoconference dedicated machine at
patient's home and for a
> central "Call Center",
connected, again via videoconference
> dedicated machines, to some
caregivers'/medicians' houses/hospitals.
> Would it be possible, and eventually how, to
"tunnell" our
> VenueServer(s) in order to link it/them to
the Mbone? How, and which
> pre-requisites are needed in order to
require/gain access to the
> Mbone infrastructure?
> Thank you, as always, for your support,
> Faber B.
>
> "Andrew A Rowley" <Andrew.Rowley@xxxxxxxxxxxxxxxx> scritti il
> 11/05/2006 12.44.34
>
> > Hi,
> >
> > As far as I understand it:
> > 1) The IP is a real multicast IP, with
global scope.
> > 2) I think Argonne
has reserved the IPs that they use with IANA. If
> > you want to run a venue server, I would
advise you do the same, or
> > use your GLOP space. At the AGSC
we only use static addresses. The
> > server keeps track of the IPs in use
internally – no talking is done
> > between servers.
> > 3) This is standard multicast routing.
Vic and rat communicate
> > directly with other vics and rats once
they are running – the only
> > use the venue server to get the
addresses (unless you are using
> > unicast, in which case there is a bridge
somewhere in the middle.
> > This bridge takes your unicast traffic
and forwards it to multicast,
> > and vice versa).
> > 4) Multicast address routing works
differently from unicast address
> > routing. Basically, your router
must be multicast enabled to allow
> > multicast to work from outside the
router. It is possible that it
> > will allow multicast to work inside the
LAN without this, but I am
> > not too sure. Your network card
will respond to both the 192
> > address assigned to it, and multicast
addresses, provided it has
> > “joined” the multicast group i.e. it has
sent and IGMP message to
> > the router saying that it wants to joint
the group and receive
> > traffic addressed to that group.
> >
> > There may be some things that are not
quite right in the above, but
> > I’m sure someone on the list will
correct me if this is the case.
> >
> > Andrew J
> >
============================================
> > Access Grid Support Centre,
> > RSS Group,
> > Manchester
Computing,
> > Kilburn Building,
> > University of Manchester,
> > Oxford Road,
> > Manchester,
> > M13 9PL,
> > UK
> > Tel: +44(0)161-275 0685
> > Email: Andrew.Rowley@xxxxxxxxxxxxxxxx
> >
> > From: owner-ag-tech@xxxxxxxxxxx
[mailto:owner-ag-tech@xxxxxxxxxxx]
> > On Behalf Of
Fabrizio.Berdondini@xxxxxxxxxxxx
> > Sent: 11 May 2006 08:29
> > To: ag-tech@xxxxxxxxxxx
> > Subject: [AG-TECH] Venues Addresses:
infrastructural question
> >
> >
> > Hello all,
> > while trying to resolve some troubles in
our internal subnet
> > configuration, I was wondering how
*exactly* the VenueServer
> > assigns/manages addresses for the
venues. What I know, from official
> > documentation and from Thomas D. Uram
messages inside this m/list,
> > is that the management of the IP for the
venues can be either static
> > or dynamic, meaning that I can assign a
fixed IP to each venue (one
> > for video, one for audio, and it will
have always the same) or let
> > the venueserver assign the IPs inside a
variable range, giving them
> > to audio/video of a venue when the first
user asks to enter it,
> > while releasing them when the last person
into the venue leaves it.
> > What I'm not able to understand is:
> >
> > 1) is the IP assigned to audio/video for
each room a *real* IP (a
> > multicast IP publicly visible over the
internet i mean) or is there
> > some kind of alias/routing sistem
underlying somewhere?
> > 2) In the first case, how can the venue
server understand a
> > particular IP is "free" or
"used" by someone else (i.e. another
> > venueserver or another service)?
> > 3) In the second case, how is the
routing done? How can the
> > venueserver address the two applications
Vic and Rat (with some kind
> > of DNS i guess) to the right IP?
> > 4) Again in the second case, how can the
VenueServer assign/manage
> > addresses in ranges like 224.xxx.xxx.xxx
when the allowed IPs inside
> > a LAN are restricted to a range that
goes from 192.168.2.10 to
> 192.168.2.150?
> >
> > I'm not sure if I could explain clearly
what I'm looking for, but
> > this matter, as far as now, is very
critical to me, I'm ready to
> > give any further clarification and open
to every suggestion and
> information.
> > Thanx as always,
> > Faber B.