Polycom's VSX 5000

The VSX 5000 can connect to an Ethernet network or as many as four ISDN BRI links. I connected one of the units to a fast Ethernet switch. Stereo RCA jacks supply the audio output, and an S-video jack brings video signal. If your conference-room TV doesn't have an S-video input jack, a $25 S-video-to-RCA adapter will do the trick. You also can mirror content through a second S-video port, or output video via a VGA port to a standard computer monitor, but only 800x600 and 1024x768 resolutions are supported for VGA output.

The built-in camera was reasonably good: Images were sharp and clear, and the color was nearly accurate. Although you can't make the camera head swivel by remote control as you can with the higher-end Polycom VSX units, you can move it left or right manually. Digital pan and tilt can be accomplished using the remote. Although the zoom isn't optical--there are no moving parts, it's all done by digital manipulation--the image is relatively clear at maximum zoom.

A second set of jacks let me connect an additional video input signal, such as a VCR or DVD player. My PowerBook has an S-video-out jack, and I used a miniplug-to-RCA converter to connect audio. The VSX 5000 doesn't come with a VGA input jack, though an add-on is available. I loaded up a PowerPoint presentation with background music and configured the Mac to appear as Camera 2. Finally, I plugged in the triangular Polycom stereo microphone.

I connected the second VSX 5000 unit to a TV in another room, connected it to a pair of stereo speakers and ran an Ethernet line to it. My first goal was to see if the units could communicate on the same switch before testing over the Internet.Initial software configuration was easy. I answered a few questions, such as whether to use DHCP or static IP, entered my location and set the admin password. I then entered the IP address of my other VSX, and a connection was made. The video was remarkably clear and had a near-broadcast-quality refresh rate.

Next, I tested the stereo audio feature. I had a co-worker stand to the left side of the microphone at the remote unit. As the co-worker spoke and walked to the right side of the mike, the audio shifted from left to right speaker. Although subtle, the stereo sound added richness to the audio.

I switched the second VSX unit over to the Mac. TVs rarely display video as sharply as computers do, so I wasn't surprised when the text on the PowerPoint slides appeared a tad fuzzy. Still, the slides were easily readable at 20 points or greater.

Streaming Video

To test streaming, I connected to each VSX unit using a Web browser, through which I could initiate a call, change the configuration or even watch a meeting by streaming video. I would have liked password protection for the streaming feature to be readily available, but it's disabled by default. In my test, I streamed video to a computer on my LAN.

Audio and video are streamed off the VSX through QuickTime. The camera follows whichever VSX unit is producing the predominant audio. A quick reply like "yes" won't change the camera's focus, nor will background noises like the sound of coffee mugs being set down. But if the camera detects someone speaking a few words near another unit, the image will switch over to that unit.I tested out the connection over the Internet and found the VSX easily detected and traversed NAT devices. My SonicWall router is H.323-compatible, so I didn't have to modify any router rules. When I used a non-H.323-compatible NAT device, however, I needed to forward a few ports to the VSX. In either case, I was able to hold a conference.

Phone Home

I then decided to conference between my home and the Syracuse labs, which are connected to the Internet by OC-3. After setting up both units, I had my home VSX initiate a call by dialing the IP address of the lab VSX. The units took about 10 seconds to autonegotiate and determine the connection speed and best compression algorithm and protocol to use.

Both ends received near-broadcast-quality content in stereo--impressive! At times, the frame rate dropped, making the connection choppy, but overall it was an improvement over other systems I've tested. To judge the quality for yourself, check out my demo (available as either RealVideo or Quicktime). For comparison with your environment, my home connection has a downstream speed of about 5 Mbps and an uplink of about 384 Kbps.

Polycom includes a few bonus features with the VSX. An address book, called a directory, lets you store names and calling info (IP, DNS or ISDN number). In addition, you can schedule calls for the unit to dial automatically at specified times; the only downside is that the unit you're calling must be in the directory when you schedule the call. Call statistics, trace route, ping and AV calibration tests are also available.Michael J. DeMaria is an associate technology editor based at Network Computing's Syracuse University's Real-World Labs®. Write to him at [email protected].

My video demo of Polycom VSX 500 can be viewed one of two ways