thumb|Mbone session directory (sd), February 1996
Mbone (short for "multicast backbone") was an experimental backbone and virtual network built on top of the Internet for carrying IP multicast traffic on the Internet. It was developed in the early 1990s and required specialized hardware and software. Since the operators of most Internet routers have disabled IP multicast due to concerns regarding bandwidth tracking and billing, the Mbone was created to connect multicast-capable networks over the existing Internet infrastructure.
During March 16–20, 1992 the first significant use of the MBONE took place from the Internet Engineering Task Force (IETF) meeting in San Diego with 20 sites listening.
On May 23, 1993, Wax or the Discovery of Television Among the Bees was streamed over the Mbone, becoming "the first movie to be transmitted on the Internet."
On June 24, 1993, the band Severe Tire Damage was the first to perform live on the Mbone.
On November 11, 1993 Sky Cries Mary performed on the Mbone from Bellevue, WA sponsored by Starwave.
On August 23, 1994, the band Deth Specula broadcast the first live concert over the Mbone.
A November 1994 Rolling Stones concert at the Cotton Bowl in Dallas with 50,000 fans was the "first major cyberspace multicast concert." Mick Jagger opened the concert by saying, "I wanna say a special welcome to everyone that's, uh, climbed into the Internet tonight and, uh, has got into the M-bone. And I hope it doesn't all collapse.").
By 1995, there were M-bone links in Russia, as well as at the McMurdo Sound research station in Antarctica.
A revived mboned (mbone deployment) working group was chartered by the Internet Engineering Task Force in 2014, as a forum to coordinate and document multicast deployment challenges and best practices.
Details
The purpose of Mbone was to minimize the amount of data required for multipoint audio/video-conferencing.