Table 1: Characteristics of Alternative Overlay Technologies
Type of
Network | Bandwidth | Latency | Mobility | Typical Video
Performance | Typical Audio Performance |
In-Room/Building
(Radio Frequency
Infrared)
| >> 1 Mbps
RF: 2-20 Mbps
IR: 1-50 Mbps
| << 10 ms
| Pedestrian
| 2-Way, Interactive, Full Frame Rate (Compressed)
| High Quality, 16 bit samples, 22 KHz rate
|
Campus-Area
Packet Relay
| approx. 64 kbps
| approx. 100 ms
| Pedestrian
| Medium Quality
Slow Scan
| Medium Quality
Reduced Rate
|
Wide-Area
(Cellular, PCS)
| 19.2 kbps
| > 100 ms
| Pedestrian/
Vehicular
| "Video Phone" or Freeze Frame
| Asynchronous "Voice Mail"
|
Regional-Area
(LEO/VSAT
DBS)
| Asymmetric Up/Down
100 bps to 4.8 kbps
12 Mbpbs
| >> 100 ms
| Pedestrian/
Vehicular
Stationary
| Seconds/Frame
Async Video Playback
| Asynchronous
"Voice Mail"
|