Each router in a group of routers (110R.2, 110R.3) includes an interface (P4) assigned a common virtual address for multicast (VAM). The common VAM is advertised in router advertisings for multicast traffic; other addresses are advertised for unicast. The member routers in the group share multicast forwarding databases. Increased throughput is therefore provided for multicast traffic without traffic replication. Any router in the group can service requests from end-point sources and receivers of multicast traffic, e.g. requests to join or leave a multicast group, or requests presented as multicast packets for forwarding to a multicast group.

A multi-domain network (5) has a Hierarchical Path Computation Element, H-PCE, architecture comprising a Parent Path Computation Element, P-PCE (31) and a Child Path Computation Element, C-PCE, (21-25) at each of the domains (11-15). A C-PCE (21-25) determines summarised domain topology information about the domain (11-15). The summarized domain topology information comprises at least one of: an indication of whether the domain (11-15) is capable of supporting Point-to-Multi-Point services; an indication of whether a node of the summarised domain topology is capable of supporting a branch point for Point-to-Multi-Point services. The summarised domain topology information is sent to a P-PCE (31) via a communication interface (35). The P-PCE (31) computes an end-to-end Point-to-Multi-Point tree using a topology based on summarised domain topology information (32) received from the Child Path Computation Elements. The P-PCE (31) requests each C-PCE (21-25) of a domain in the computed end-to-end Point-to-Multi-Point tree to compute an intra-domain path.

In one embodiment, a method includes computing at a controller, a primary path and a backup path for transmittal of multicast data from service nodes in communication with the controller and a multicast source to access nodes in communication with multicast receivers, and transmitting from the controller, information for the primary path and the backup path to the access nodes for use by the access nodes in receiving the multicast data on the primary path and the backup path, and switching transmittal of the multicast data to the multicast receivers from the primary path to the backup path upon identifying a failure in the primary path to provide fast reroute at the access nodes. A multicast control plane runs in the controller without operating in the access nodes. An apparatus is also disclosed herein.

Even when a plurality of communication parameter providing devices exist, a communication parameter setting process is enabled. When a plurality of communication parameter providing devices exist, one of the communication parameter providing devices is determined. For example, all the communication parameter providing devices are caused to stop the providing process. Alternatively, a user is allowed to select a communication parameter providing device. Alternatively, a communication parameter providing device is determined in accordance with a predetermined rule.

Techniques are described for enhancements to Protocol Independent Multicast (PIM) to enable a last hop router (LHR) to perform source discovery and directly build or join a source tree. According to the techniques of this disclosure, the LHR builds a communication channel with a rendezvous point (RP) router and requests source information for at least one multicast group for which the LHR has interested receivers. The RP responds to the request by looking into a register database maintained by the RP and sending source information indicating at least one source that is actively providing traffic for the at least one multicast group. Based on the response, the LHR initiates a (S,G) PIM Join message toward the at least one source for the at least one multicast group to directly build or join at least one source tree.

Aspects of the subject technology relate to systems for arbitrating direct forwarder (“DF”) instantiation between VPC peers used to facilitating the transport of bidirectional multicast traffic over a L2/L3 network boundary. In some aspects, arbitration of DF instantiation on a given VPC peer can include determining a first set of metrics for a first VPC switch, determining a second set of metrics for a second VPC switch, and determining, at the first VPC switch, whether to instantiate a designated forwarder (DF) operation based on a comparison of the first set of metrics and the second set of metrics. Methods and machine-readable media are also provided.

Architecture that provides reliable communications of broadcast data (e.g., a message) in a collection of nodes. Each node in the collection is assigned a range of identifiers in a token. The union of the tokens for all nodes is the entire identifier range space. Each node that receives a reliable broadcast message from an originator node acknowledges receipt of the message using its token. One or more intermediate nodes forward the message from the originator node to other nodes with which the originator node has no direct communications (multi-level node structure). The indirect nodes each send acknowledgements back to the parent nodes (which can be an intermediate node) which combine the tokens to ensure the entire range space for the associated assigned token range is covered. The originator node ultimately receives tokens to compute if all nodes have received the message.

A method, apparatus and computer program product for providing quick designated router transitions in broadcast networks is presented. An Alternate Designated Router (ADR) in a network detects node failure of a Designated Router (DR) prior to other nodes of the network detecting the failure of the DR. In response to the detecting node failure of the DR, the ADR floods the network with a link state packet of a pseudonode within the network. At least one other node of the network detects failure of the DR. The at least one other node computes routes to take into account the failure of the DR by the at least one other node of the network, wherein there is minimal traffic loss since the pseudonodes link state packet is already present before the computing routes takes place.

A packet forwarding system includes: a plurality of first relay apparatuses connected to one another; a plurality of second relay apparatuses that include a plurality of ports and that are connected to the plurality of first relay apparatuses; and a control apparatus that configures a plurality of trunks, each serving as a virtual logical link, by using a plurality of physical links between the first relay apparatuses and the second relay apparatuses. The control apparatus determines a designated port for each of the plurality of trunks from among constituent ports of the each trunk. When one of the plurality of first relay apparatuses receives a predetermined control target packet from one of the plurality of second relay apparatuses, the control apparatus causes the plurality of first relay apparatuses to transmit the predetermined control target packet via a first relay apparatus including a designated port for one of the plurality of trunks, to which a port of the one first relay apparatus receiving the predetermined control target packet belongs.

In one embodiment, a multicast communication is received at a particular node of a plurality of nodes receiving the multicast communication in a network. The particular node selects a subset of subcarriers using a probabilistic data structure, such that each of the plurality of nodes selects a respective subset of subcarriers using the probabilistic data structure. The particular node transmits an acknowledgement of receipt of the multicast communication on the subset of subcarriers selected by the particular node. The transmission occurs simultaneously with transmissions of acknowledgements from the other of the plurality of nodes.