| Virtual network - uses a network of special (up and coming) routers that support multicast |
| One-to-many and many-to-many network delivery services for applications such as videoconferencing and audio where several hosts need to communicate simultaneously |
| Teleconferencing can be done in the world of Internet (variable packet delivery delays, bandwidth limited) |
| IP multicast addressing (RFC 1112), IP Class D, 224.0.0.0-239.255.255.255 |
| Sun - multicast (modified kernel), SGI mrouted, dedicated routers |
| Audio -frequent dropouts |
| Video - 1-4 fps over Internet |