For the past several years, I’ve been using a slide with the continuum of videoconferencing technology in my workshops. I decided it’s time to write up my thoughts about this so we can all refer others to the choices for videoconferencing. This post was co-written with guest blogger Lori Colwill.
The continuum starts at the lowest level and moves up from there.
Desktop VC: Skype, iChat, etc.
- Proprietary (i.e. Skype only connects to Skype, iChat only connects to iChat, etc).
- Disadvantage: Lack of echo-cancellation or stability of the call can make it difficult to use with a classroom of students
- Disadvantage: Some security concerns for classroom use
- Disadvantage: Lower quality and inability to connect to most content providers
- Options: Skype, iChat, GoogleTalk, TokBox, TinyChat, FaceTime and others
Desktop VC: Open Source H.323
H323 is the standard for what is also referred to as IP based videoconferencing. With H323 you can connect to any other H323 device (in theory).
- Ekiga and XMeeting
- Connects to most H323 standard videoconferencing units
- Disadvantage: No echo-cancellation can make it difficult to use with a classroom of students
Desktop VC: H.323
- LifeSize Desktop: software only; no server required (8/12/09: It’s SIP only; not H323) (3/4/11: If it’s installed with a server and bridge, you can connect to H.323)
- Polycom PVX software: $120 ish plus webcam
- Polycom CMA: desktop software that requires a server
- Tandberg Movi: desktop software that requires a server
- Echo-cancellation may be a problem
- Rigging audio and video from a desktop system to work in a classroom can be challenging
Small Room Systems: Fixed Camera H.323
- Under $5000
- Polycom V500, VSX 5000
- LifeSize Express w/Focus camera
- Cameras have limited or no movement
- Designed for small conference rooms, 3-7 people
- Easy to receive content from content providers etc., but difficult to use to have students present for events like Read Around the Planet and other collaborative projects
Classroom Systems: H.323 SD
- SD is standard definition
- Range from $3000-$9000
- Ask your vendor for an “entry level” unit
- As of summer ’09 most of the schools and content providers I connect with have this level
- The older units are “set top” units that were designed to sit on a TV; newer units separate camera & codec to accommodate flat screen monitors
- Ability to connect a computer and document camera for presenting
- Great camera movement, ideal for classrooms
- Polycom VSX 7000 and 8000 series (older)
- Polycom QDX (newer, faster, better, cheaper)
- Tandberg 770, 880, 990 MXPs (older)
Classroom Systems: H.323 HD
- HD: High definition.
- To take full advantage of HD, calls need to be at 1-4 M. Most schools don’t have that bandwidth available; most content providers still make calls at 384K.
- It’s an investment in the future of the technology. In theory, soon we’ll all have the bandwidth to upgrade to HD.
- Lifesize Express, Express 200, Team MP, Team 200, Room, and Room 200
- Polycom HDX 7000, 8000 9000 series
- Tandberg QuickSet C20 (newer, entry level HD unit)
- Tandberg Edge MXPs 75, 85, 95
A few words about installing a “cart” vs. installing a “room”.
- A cart installation is usually a classroom system (see above)
- plus a monitor (or a projector i.e. Tandberg Media Place)
- installed on a cart
- with one microphone on a 30 foot cord that can be moved around the classroom easily as needed.
- A simple remote can be easily learned by the videoconference coordinator.
- It might include a document camera and a way to connect a computer.
- A cart installation is usually under $10K.
- A integrated room installation is often a classroom system
- plus two to four monitors
- with a presentation stand for teaching over videoconferencing
- plus ceiling and/or desk microphones
- plus a fancy lots of buttons touch panel for controlling the system (usually AMX or Creston)
- plus lots of peripherals: computer, document camera, extra inputs, DVD/VCR
Classroom teachers are intimidated by room installations! So are students. The cart is much simpler and easier if you plan to use VC for curriculum videoconferencing. The room may be better for full length courses.
- really fancy expensive executive meeting systems designed to make you feel like you’re in the same room
- includes special paint and lighting
- can’t see them used in schools anytime soon, but this is why you want to expose your students to VC – they will use it in their business work
Videoconference Network Infrastructure
If you are part of a videoconference network (through your state, region, or large school district), you may learn about videoconference network infrastructure.
- MCUs: Bridges which allow multiple participants in multiple conferences at the same time
- IP VCRs: Allows for recording and streaming of videoconference content
- Firewall transversal units: Used to solve the challenges of H323 through your firewall (only get this if you can’t make it work any other way in my opinion)
- Gateways for IP to ISDN, H.323 to voice, H.323 to SIP and H.323 to proprietary protocols (Thx Craig!)
- Gatekeepers: for dialing plans
- Management software: for places that manage many units: for scheduling, upgrading software, providing directory services, etc.
Now that you see the big picture, what should you do? If at all possible, try for an entry-level unit or classroom H323 unit. Talk to your school district or regional tech and see what the plan for videocoferencing is for your area. You may have access to VC and not even know it!
Comments, thoughts? Favorite VC vendor missing? Please comment, share and add to our knowledge!
Revision 8/6/09 with LifeSize based on comments below.
4/9/10 Addition: You may also be interested in the VC Continuum in My Schools
Filed under: Techie Stuff