310 results about "Spanning Tree Protocol" patented technology

A multiple instance spanning tree protocol (MI-STP) creates a plurality of active topologies (i.e., loop-free paths) within a computer network. These active topologies may be established through the exchange and processing of multiple instance spanning tree bridge protocol data unit messages (MI-STP BPDUs) by the intermediate network devices within the network. The active topologies are preferably created independently of any virtual local area network (VLAN) designations defined within the network. Once the active topologies are defined, each VLAN designation is then mapped to a single active topology, although multiple VLAN designations are preferably mapped to the same active topology to provide load balancing.

Methods and apparatus that form the basis of an alternate spanning tree protocol that may be used, for example, to identify rings within a properly converged network configured by the spanning tree protocol (STP) or rapid spanning tree protocol (RSTP) are provided. With the knowledge of these rings, the alternate spanning tree has predetermined an alternate port that can restore connectivity without further computation in case of a link failure, thereby providing for extremely fast reconvergence.

A method of managing a computer network switch is disclosed. The method has the steps of: setting a port of the switch to root guard protected status (RG status); selecting by a spanning tree protocol (STP) the port as a designated port; and setting said port into blocked status, in response to said port being both in root guard protected status and selected by STP as a root port. By setting a port to root guard protected, the port is prevented from becoming a designated port, and so then forcing the root port to remain in a desired core network.

A computer network includes a core network connected with first and second Ethernet access domain networks, each of Ethernet access domain networks including a user-facing provider edge (u-PE) device, a primary network-facing provider edge (n-PE) device, a redundant n-PE device, and a plurality of aggregation provider edge (Agg-PE) devices providing connectivity between to the u-PE device and the primary and redundant n-PE devices, the Agg-PE devices running a spanning-tree protocol (STP) algorithm. A primary data path is provided along with first and second redundant data paths that include first and second redundant pseudowires (PWs), respectively, connected across the core network, the first and second redundant data paths being blocked by the STP algorithm when the primary data path is available, the STP algorithm unblocking either the first or second redundant data path in response to a failure of the primary data path. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).