Mbone (short for "multicast backbone") was an experimental backbone 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 in order to connect multicast-capable networks over the existing Internet infrastructure.
Mbone was invented by Van Jacobson, Steve Deering and Stephen Casner in 1992.
On June 24, 1993, the band Severe Tire Damage was the first to perform live on 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.
Mbone was used for shared communication such as video teleconferences or shared collaborative workspaces. It was not generally connected to commercial Internet service providers, but often to universities and research institutions. Some other projects and network testbeds, such as Internet2's Abilene Network, made Mbone obsolete.
A "virtual room video conferencing system" (VRVS) started operation in 1997 using the Mbone, and was in operation through 2008.