[Calendar] 5-way video conferences

[Alan Bridle]

Dear calendar schedulers,

We don't get many requests for 5-site video meetings, but
there are a few occasions when people ask for them.  These
5-way video meetings have some strong consequences for our
room bookings, so here's some background.

Any video conference that involves more than two rooms
requires the use of a video "hub" to process the multiple
video and audio signals.  The hub decides which sites see
what video when, depending on who's talking.

Each of our three video hubs (CV-conf, SO-conf, NRAO-hub) can
handle only up to a four-room video meeting.

Two-site meetings don't need a video hub at all, as any video
system can call any other direct to start such a meeting,
just like a phone call.

Three or four-site video meetings can be handled by one hub.
This can be CV-conf, SO-conf or (if neither of those rooms is
involved) NRAO-hub. Many video meeting organizers know how to
make one-hub connections now.

Any video meeting that requests FIVE rooms must (a) reserve
TWO of the video hubs and (b) arrange to coordinate how these
hubs will connect to each other and to the other sites at the
start of the meeting.

In practice the 5-way requests from entirely within the NRAO
all involve the VLA site with rooms in GB, CV, the AOC and
Tucson.   There is just one good way to satisfy such
requests: both SO-conf (in Socorro room 317) and CV-conf (ER
Room 311) must be involved.
 
(SO-conf first calls the VLA, and then calls CV-conf, setting
up a three-way meeting hosted at SO-conf. CV-conf then calls
GB and Tucson, to make it a 5-way meeting hosted by both
hubs together.  The two hubs then sort out who sees what,
and when)

The bottom line for you as schedulers is that if you are
asked to make a reservation for such a 5-way video meeting,
please check that it includes both CV-conf (CV311) and SO-
conf (SO317).  As the other video systems in CV and at the
AOC do not contain video hubs, the only flexibility in a 5-
site video meeting is over which video system in Green Bank
is used.

Also, because of the need to connect the two hubs in a co-
ordinated way, the organizers of 5-site video meetings should
be asked to contact Gareth Hunt, Gene Runion or me to make,
or to show them how to make, the initial connections. (This
is not something that most video conferencing users know, or
need to know, how to do.)  We will all be happy to assist
users as needed to get any 5-site meetings started.

Thanks,

Alan B.