Mbone

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Mbone (short for "multicast backbone") is an experimental backbone for IP Multicast traffic across the Internet. Since most Internet routers do not yet support IP Multicast, the Mbone has evolved to connect multicast-capable networks over the existing Internet infrastructure. It is anticipated that the Mbone will eventually become obsolete as more routers understand and forward IP Multicast traffic, which is a standard feature in IPv6. The commercialization of multicast routers is difficult because there is no efficient access control capabilities to the multicast trees (multicast routers and their protocols), and because Internet Service Providers have difficulty computing charges for multicast traffic.

Mbone is currently of practical use for shared communication such as videoconferences or shared collaborative workspaces. It is not generally connected to Internet service provider, but often to universities and research institutions. Some other projects and network testbeds, such as Internet2's Abilene Network, have made Mbone obsolete.

1 Details
2 See also
3 External links
- 3.1 Historical clients

[edit] Details

MBONE is a virtual network built on top of the Internet; Invented by Van Jacobson, Steve Deering and Stephen Casner in 1992. The purpose of MBONE is to minimize amount of data required for multipoint audio / video-conferencing

MBONE is free; it uses network of mrouters that can support IP Multicast; enables access to real-time interactive multimedia on the Internet

Many older routers do not support IP Multicast; to avoid this we must set up tunnels on both ends also known as a tunneling protocol ; multicast packets are encapsulated in unicast packets and sent through a tunnel;

MBONE uses a small subset of the class D IP address space (224.0.0.0 - 239.255.255.255) assigned for multicast traffic. MBONE uses 224.2.0.0 for multimedia conferencing

Characteristics:
- topology: combination of mesh and star networks
- IP addresses: 224.2.0.0; routing schemes: DVMRP, MOSPF
- session registration: IGMP protocol
- traffic requirement: audio 32-64 kbit/s, video 120 kbit/s

MBONE tools:
- Videoconferencing: vic -t ttl destination-host/port (supports: NV, H.261, CellB, MPEG, mJPEG)
- Audioconferencing: vat -t ttl destination-host/port (supports: LPC, PCMU, DVI4, GSM)
- Whiteboard: wb destination-host/port/ttl
- session directory: sdr