[75] Inventors: Paul T. Francis, Morristown, N.J.; [75] Inventors: Paul T. Francis, Morristown, N.J.; Anthony J. Ballardie, Alstonefield; Anthony J. Ballardie, Alstone?eld; Jonathan A. Crowcroft, London, Jonathan A. Crowcroft, London, both of England both of England [73] Assignee: Bell Communications Research, Inc., [73] Assignee: Bell Communications Research, Inc., Livingston, N.J. Livingston, NJ.
Alternatively, the packet may contain voice data 1) or routers a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, of a speaking teleconference participant at a source s (shown as squares in FIG. 1).
The router r7 transmits a copy of the received packet to the destination node d3 5 uses a modified reverse path forwarding algorithm to copy of the received packet to the destination node d3 uses a modi?ed reverse path forwarding algorithm to via the routers r9 and rlO.
The copies of the packet are then transmitted ing table is indexed by the multicast address of the core via the appropriate links to the member nodes.
FIG. 7 depicts a forwarding table at a node of the communicates a request to join the particular multicast communicates a request to join the particular multicast FIG. 7 depicts a forwarding table at a node of the internet of FIG. 6 in the process of being added to a group to a designated router.