Tag Archives: Polycom CMA Desktop

The VC Continuum I Recommend to My Schools

As we end this week of talking about desktop VC, I thought it might be helpful for me to share the continuum of videoconferencing that I recommend to the schools in the two counties that I serve. This may be helpful to know the perspective I’m coming from when I evaluate desktop VC.

I’ve made a more generic overview of the videoconferencing continuum before, but here’s what I recommend to my schools.

What We Have Already

Remember we have:

  • 70 Polycom Viewstations and VSX 7000 endpoints; 1 LifeSize 200 installed last week; 1 Polycom QDX  6000 installed last fall
  • Tandberg infrastructure: MCU, Gatekeeper, IP-ISDN Gateway, and Tandberg Management Suite for scheduling

I still have about another 20-30 schools in my service area that don’t have VC in their school building.

How We Use VC

  • We do about 700-900 videoconferences a year.
  • All our videoconferences are with standards based H323 units.
  • 60% of them are with other schools – collaborative projects etc. 59% of those are out of our service area; 45% of them are out of state; 5% are out of the U.S.
  • 15% of our VCs are with content providers: zoos, museums, GNG, NASA, etc.
  • 15% of our VCs are ASK programs: interviews with authors or specialists: either ones we run for our schools or TWICE ASK.
  • The last 10%  are meetings and professional development, mostly within county or content we get from the state.
  • Many of the teachers just walk into the room to do the VC. The call has already been set up by me or the VC coordinator in the school, and presets are already set if needed. All the teacher has to think about is the muting and unmuting if they are in a multipoint, and the presets if their class is presenting or participating in an ASK program, and of course preparing their students on the curriculum side. Often I’m listening to the VC so if something goes wrong, I can fix it for the teacher.

Ideally a VC cart

Most of our equipment was purchased with grants. When that is possible, I prefer an installation that includes:

  • The H323 videoconference system: LifeSize, Polycom, or Tandberg
  • HD if it can be afforded
  • A sturdy but lightweight cart
  • A 37 to 50 inch monitor
  • A document camera
  • An Avermedia QuickPlay to connect the computer in via S-Video (yes, yes, I know, lower quality, but guaranteed to work with anything we connect to) or any other method that connects the computer that is NOT H.239/People Plus Content/DuoVideo
  • In our latest installation we also had a DVD/VCR, but I wouldn’t recommend that now. My schools never use it.
  • If possible, installed with an IP address NATed. In only one district do we have a firewall traversal unit, and we’re trying to make it work without it because the extension dialing is such a pain.
  • 3 years maintenance on the VC system at least! Usually my districts can’t afford maintenance after the grant runs out, so if we’re using a grant we always do 3 years maintenance. I also strongly urge any districts buying their own unit to buy 3 year maintenance on it.
  • This list is about $7000-9000.

Next Best, Mobile Within the District

Two of my districts were not eligible for the latest RUS grant. When we switched from ISDN to IP in 2005, their PictureTel Concordes were obsolete.

  • These two districts have a Polycom VSX 7000 in a box.
  • It connects to the TV in the classroom or a projector.
  • If a document camera is needed, it is borrowed from elsewhere to use with VC.
  • The district tech moves it from school to school, and updates the network settings as it moves.
  • This setup is just the codec only. So it could be as low as $2000-5000.

Next Best, Buy Old Units

  • In a couple of my other schools, they purchased refurbished or gently used VC systems. In one case from eBay. In the other case from their network services provider which had some extra Polycom Viewstations kicking around. (Another place would be The Videoconference Store, which sells used systems.)
  • Both of these scenarios use existing TVs/projectors/carts.
  • This setup could cost around $1000-$3000.

Interactive 21st Century Classrooms

That brings me to the next scenario: 2-5 school districts that have or are purchasing interactive whiteboards and installing them in every classroom. Each of these districts sees the value of VC as we use it in the curriculum. They all have teachers who are tired of getting the cart to VC in their classroom or going to the library or fixed room. (Kind of funny really. I remember when they were tired of busing to the high school to VC.)

These districts COULD spend their funds to upgrade their existing system to HD. But the possibility of VC in every classroom is intriguing and tempting.

  • Whiteboard plus short throw projector means the display is already there.
  • Some of these teachers are already doing Skype on their interactive whiteboard. So why not H.323 also!?
  • It needs to cost the same or less to put VC in every classroom than they would spend to upgrade their carts to HD and 50 inch LCD monitors.
  • H.323 standards based videoconference is a must.

This is one of the main reasons I’ve been investigating desktop VC (in case you missed the posts, so far I’ve looked at Mirial, Vidyo, and Polycom CMA Desktop. In the future, also need to look at Tandberg Movi and LifeSize Desktop at least).

Desktop VC On a Cart

Finally, the other scenario is for our private schools and districts that don’t have VC yet, but definitely want it. They aren’t eligible for grants – not poor enough or not rural enough or not a public school. But they also don’t have enough funding to buy the ideal VC cart or even the refurbished units. They need something under $500.

  • They could use an existing laptop and projector cart (many of them are sharing the projector in the school this way already).
  • Plus a webcam for $100-ish.
  • Plus a microphone for $150-ish. (I’ve tried out the Clear One Chat in a classroom situation with very poor results; next I’ll be trying the Phoenix Duet.)
  • Plus $120 for Polycom PVX or something similar with one of the other options that I’m exploring.
  • HD is NOT essential as their projector and laptop are probably older anyway.

So, that’s where I’m coming from as I evaluate desktop VC. I’m trying to get more VC to my schools. More H323 VC!

What do you think? Is this similar to what you recommend to your schools? What would you add or change? Please feel free to comment!

Thinking about Polycom CMA Desktop

This post continues the journey to figure out how to get videoconferencing in the 21st century classrooms in our county. Remember my original vision from 2008 as well. The other tool that is really catching my attention is Polycom’s CMA Desktop.

When I first learned about Polycom CMA Desktop, it had two drawbacks: the requirement to be on the same network as the CMA server (via VPN or physically), and it didn’t work on the Mac. Both of these have since been resolved.

In the month of March, thanks to Aaron Schippert at Saginaw ISD, I was able to play with the Polycom CMA Desktop and I’m really quite excited about it. I’m thinking in particular of two of my districts installing interactive whiteboards in all their classrooms, and wanting VC in every classroom if it can be done well.

I’m also thinking of my schools that still don’t have VC, as well as participants from my March session of Planning Interactive Curriculum Connections who were using only Skype. Once they learned what they were missing in H323 content, they were so eager to get H323 VC, but funding is a huge problem. One of the participants had set up a Skype cart for their school. What if, for a small fee, they could get H323 VC on their Skype cart as well??!!

So here’s my thoughts from testing and learning about Polycom CMA Desktop:


  • It’s super easy like Skype. It has your contact list and an easy call button. It will call an IP address or another person (by name) registered to the CMA server.
  • No echo! Echo cancellation is built in. In our test, we didn’t have to install an additional mic. Polycom CMA Desktop used the audio from the Logitech camera. With no echo. (Better than Skype! I’ve heard a lot of echos on Skype calls!) Echo cancellation is a huge issue when trying to morph desktop VC to work in a classroom.
  • Quality. In my initial tests with a login from Saginaw ISD, the video and audio is GREAT!
  • Scalability and cost. The cost structure is definitely a pro. After investing in the server, you can have unlimited downloads of the client software!!!  Of course, depending on how many licenses you buy (100, 200, 400, 500, & up), you can only have that many people logged in at the same time; and a slightly smaller percentage of those actually in a call at a time depending on setup. But teachers aren’t going to use VC all the time, so if you can just have them logout when they aren’t using it, this resource could stretch a LONG ways in education! Especially if you figure from the 10% use as normal use of VC – which I think is pretty close to a reasonable number when looking at the most VCs I have at the same time and how many codecs I support.
  • It works on the Mac! (starting April 30). Yay! This of course is critical. Not interested without Mac support.
  • When installed with a Video Border Proxy (VBP), it works great across firewalls. No configuration changes to the firewall! I tested a login borrowed from Saginaw ISD while they had a demo VBP at their site. We installed it on a PC behind our firewall, hooked up a 3+ year old Logitech camera, logged in, and we were up and running. Beautiful. Connected fine to several H323 units off our network. No problem. (Note: I understand from talking our sales guys at Polycom that this may not work as well with corporate high security firewalls. In that scenario they recommend a VBP at each network edge.) Just imagine giving an author or expert a temporary login so they can come in via H323! I’ve learned that the reason this works is the new h.460 extension to the h.323 standard. It allows the server to set up a secure connection with the desktop to easily traverse the firewall. Note also that without the VBP, each user off the network has to VPN to connect to the CMA server. Not a good solution in our scenario.
  • Dialing. Another benefit of installing with the VBP is the dialing benefits. I’ve learned that gatekeepers really do help with dialing. For example, if a VBP is installed with the Polycom RMX, the Tandberg bridge can dial in with the alias@IP format (using the VBP’s IP). I wasn’t able to actually test this, but I was told that Polycom endpoints off our network could dial in to a Polycom CMA Desktop user with the IP##alias format; and Tandberg endpoints off our network could dial in with the alias@IP format. This means that I could call out to a classroom involved in a VC, and the teacher would only have to have the computer on and logged into CMA Desktop. I have several districts where they need this level of support. Dialing in/out via H323 is another essential feature for our use of videoconferencing.


  • H.239. As I got excited and started talking to my districts interested in VC in every classroom, they wanted to be able to share the computer. That means H.239 with Polycom CMA Desktop. If you’ve been reading my blog, you know I never use H.239 if I can help it, and I find it incredibly frustrating. There are too many situations where it fails. With a regular unit, that is easily solved by zooming the camera in on the laptop. But how would that work when the laptop IS your VC system? After learning how LifeSize handles H.239 last week, my expectations were raised. I thought I’d test to see how CMA Desktop works when sharing content with the other site having H.239 turned off. Just as expected, it did not allow sending content to Polycom MGC, Tandberg bridge, Codian bridge, Tandberg MXP endpoints all with H.239 turned off. The anomaly was my Polycom VSX 7000 (version which accepted H.239 content whether or not H.239 was turned on, but that must be a fluke. So now I have to decide how critical desktop sharing is to my dream. I don’t want teachers to spend classroom time preparing a presentation and then find out the partner class can’t receive it. Note to Polycom, in a future version, when CMA Desktop detects the other site can’t receive content, could it just send the computer screen and not the webcam? Please!
  • So far that’s all I can think of for a con. What about you?

Hmm. If H.239 didn’t work with the partner school, what about taking the little webcam and facing it to the laptop screen? For that matter the webcam could serve as a document camera by moving it around too. I’ll have to think about this more.

Server Based VC

Initially in my interest in morphing desktop VC for the classroom, I wasn’t interested in server based videoconferencing. I keep thinking of the schools that install Polycom PVX and are up and running tolerably well. It is such a low cost entry starting place. How would they get started without that? Of course PVX is painful to get working through the firewall. But still, it’s an easy low cost starting place (read a success story here).

As I’ve learned more, though, I understand that Skype works so well because it too is using a “server” – a distributed system/server of course – but still it’s not stand alone. It’s the server that helps make the VC on the desktop so super easy.

So, now I’m thinking, educational service agencies or others could offer a service to schools to get access to Polycom CMA Desktop for less than the cost of the school/district getting their own server. This way tiny schools that want to start with H323 VC could get started without investing in a $8K cart or their own server. Then as they have funds they could upgrade to a full codec/cart once they saw the benefits of additional peripherals and quality.

Dr. Phil’s Choice

While I was thinking about this whole issue in March, I ran across this article on how Dr. Phil switched from Skype to Polycom CMA Desktop (and other endpoints/infastructure). Very very interesting!


This post concludes (for now) my little journey into desktop VC. I realize some glaring omissions include LifeSize Desktop and Tandberg Movi. But I don’t know any K12 people who have an installation that I could play with and learn about in an unbiased fashion. Plus spring break is about over and I’m about to get sucked into the last 2 months of busy VCs for the school year. So feel free to comment if you have anything to add to this thread and I’ll try to add more to it later. Maybe at the ISTE playground in June I’ll get more info to share. I also was awarded a SmartBoard with all the trimmings with the MACUL Educator of the Year award, and once that is installed, I will be playing further to see what could possibly work. That’s a summer project too.

Thanks, everyone for your comments and questions as we all learn together!

Full disclosure: Polycom funds the Berrien RESA VC Content Provider Database. They also link to my blog. However, they do not dictate, edit, or pre-approve anything I write here.