Abstract: A registration method in a system having a hierarchical structure (100) that includes a mobile node (20), at least one FA (42), at least one GFA (40) and an HA (30). The method includes the steps of: intercepting (210) a registration request (300) from a mobile node to its HA, the registration request including a first care of address (360) for the mobile node; determining (220) whether there is an existing entry in a visitor list for the mobile node; if the entry exists, updating (230) the entry; if no entry exists, creating an entry (250) in the list for the mobile node, adding (260) a second care of address as an extension to the registration request, and sending (270) the registration request with the address extension to the HA; and sending (240) a registration reply to the mobile node.

Abstract: A first device (104) receives a first message from a second device (100). Upon receipt of the first message, the first device transmits a registration request to the second device for pre-registration with a third device (102). If the second device does not receive the registration request from the first device within a predetermined time period, the second device re-transmits the first message to the first device if a communication link with the first device is still operational. If the first device receives the first message again from the second device prior to attaching to the third device, the first device re-transmits the registration request to the second device. If registration with the third device is not pending when the first device attaches to the third device, the third device transmits a second message to the first device to solicit a registration request from the first device.

Abstract: A method and apparatus are provided for minimizing dense mode multicast flooding between a local area network (“LAN”) switch and a multicast capable router. The method includes the steps of detecting a prune message from the multicast capable router, identifying a multicast group from the prune message and setting a flag within the LAN switch to disable transfer of multicast datagrams of the determined multicast group to the multicast capable router. The apparatus can include a software interface, a control information processor, and an Internet switch-memory.

Abstract: An inbound message is received over a scalable adaptive modulation (“SAM”) interface (104). The inbound message comprises a SAM layer 2 (“L2”) header and data in which the SAM L2 header encapsulates. A hardware L2 address is identified for the first device from the encapsulated data and a SAM L2 address is identified for the second device from the SAM L2 header. Once both addresses are identified, an association between the hardware L2 address of the first device and the SAM L2 address of the second device is stored. Similarly, the association may be made between the hardware L2 address of the first device and the SAM L2 address of the first device, or between an Internet protocol (“IP”) address of the first device and a SAM L2 address of a second device or the first device.

Abstract: Router elements R1, R2 of a packet network 100 using a sparse mode multicast protocol are configured as candidate rendezvous points (RPs). The candidate RPs use a virtual IP address. In each shared subnet, there is selected from among the candidate RPs a single designated candidate rendezvous point (DCRP) and zero or more virtual candidate rendezvous points (VCRPs). The DCRP serves as an active candidate RP (and when elected, performs RP functions); and the VCRP(s) serve as backup to the DCRP. The VCRP(s) maintain state information to facilitate rapid takeover of DCRP functionality upon failure of the DCRP. In one embodiment, geographically separate domains 1006, 1008 are each implemented with separate active DCRPs, defining multiple, simultaneously active anycast RPs (DCRP1, DCRP2) with MSDP peering between the DCRPs. The DCRP(s) may include backup VCRP(s) for redundancy.