Abstract: Today's Internet multicast backbone, or Mbone, is a virtual network overlaid on the mesh-interconnected global Internet through multicast-capable routers and tunnels. As a result, the performance is impaired by the heavy unicast traffics (Web) and the cost is a multiplication of number of links involved. Satellite network, however, makes the perfect multicast backbone for the Internet because of its physical broadcast nature and its economics of cost(1) = cost(n). We in HRL Labs have conducted two experiments to study the integration of satellite network with Mbone, one during IETF-40 meeting in Washington D.C. December 1997 and one during IETF-41 meeting in L.A. March 1998. In both cases, one IETF multicast session was being forwarded over DirecPC network to reach any DirecPC receiver. We also set up reflectors in both HRL (So. Calif) and U.C.Berkeley (No. Calif) that receive DirecPC multicast and forward it back to the Mbone. Through the experiments we have demonstrated the flexibility of carrying Mbone traffic over direct broadcast satellite network.
We have also collected much performance measurement data. The data show that Mbone over DirecPC performs significantly better than through the traditional Internet tunnels.