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.