Cisco Technology, Inc.

Shekher Bulusu

Ronak K Desai

Francois Edouard Tallet

Sanjay Sane

Norman William Finn

Dhananjaya Rao

Hasmit S Grover

Munish Mehta

Smita Rai

Tameen Khan

Gayatri Ramachandran

In one embodiment, a first multiple spanning tree (MST) region configuration for an MST process may be maintained at a switch in a computer network, where the first configuration has a virtual local area network (VLAN)-to-instance (VI) mapping that maps each of one or more VLANs to one of one or more MST instances in the MST region. The switch may subsequently receive a second MST region configuration that has a different VI mapping than the first configuration, and may determine one or more VLANs of the second configuration that have a different VI mapping from the first configuration ('affected VLANs'). Accordingly, in response to a trigger to apply the second configuration at the switch, the affected VLANs are blocked for a delay, and the second configuration may be applied at the switch without restarting the MST process.

Minimum disruption MST reconfiguration (MDMR)

In some embodiments, edge devices associated with a network segment are identified. One of the devices is elected as an authoritative device and any previous authoritative devices are instructed to halt forwarding network traffic to an overlay network.

Enhanced fine-grained overlay transport virtualization multi-homing using per-network authoritative edge device synchronization

A method is provided in one example embodiment and includes receiving a spanning tree protocol topology change notification (STP TCN) in a network; removing topology data for a first plurality of gateways associated with a first network segment ID that is shared by a particular gateway that communicated the STP TCN; and communicating an edge TCN to a second plurality of gateways associated with a second network segment ID and for which topology data has not been removed based on the STP TCN.

System and method for managing topology changes in a network environment

In one embodiment, a solution is provided wherein multiple virtual devices may be configured on the same physical port of a network device. For example, a first virtual device and a second virtual device may be configured to use the same physical port. A single internal spanning tree instance may be configured for both the first virtual device and the second virtual device.

Shared virtual device ports

An example method is provided and includes receiving a bridge protocol data unit (BPDU) on a particular link of a network. A port associated with the particular link is blocked in response to receiving the BPDU. The method also includes communicating a claim message to a spanning tree protocol (STP) root of the network; receiving, from a network element, a reply in which a grant bit is set; and changing the port associated with the particular link to a forwarding state.

System and method for providing a loop free topology in a network environment

A method is provided that includes configuring a first network element as a peer to a second network element. The first network element and the second network element are configured to execute a spanning-tree protocol (STP) in a network environment. The method may also include configuring a priority characteristic to be a same value for the first network element and the second network element such that both operate as root network elements for other network elements in the network environment.

System and method for managing network traffic disruption

A system and method runs a multiple spanning tree protocol (MSTP) in a computer network having a very large number of bridge domains. The computer network includes a plurality of intermediate network devices, each having a plurality of ports for forwarding network messages. Within each device, a plurality of bridge domains are defined, each bridge domain is identified by a Virtual Local Area Network (VLAN) Identifier (VID), and one or more device ports. For each port, a separate mapping of VIDs to Multiple Spanning Tree Instances (MSTIs), based on the bridge domains defined at the port, is established. Each mapping is converted to a port-based configuration digest, which is entered into Spanning Tree Protocol (STP) control messages sent from the respective port. Ports receiving STP control messages whose configuration digest values that match the configuration digests values computed for the ports are said to be in the same Multiple Spanning Tree region. Ports whose configuration digests differ from the configuration digests of received STP control messages are said to be in different regions.

System and method for running a multiple spanning tree protocol with a very large number of domains

An example method is provided and includes executing an intermediate system to intermediate system (IS-IS) protocol for a first set of network links in a network. The method also includes executing a spanning tree protocol (STP) for a second set of network links, and generating a network topology that includes using a broadcast tree system identifier (ID) as a root bridge ID for the network. The method further includes communicating the root bridge ID to a neighboring network element. In more specific examples, an STP block is communicated to a redundant link, which connects a first switch and a second switch. The first and second switches can converge on the network topology using the broadcast tree system ID.

Growing community of inventors

Fremont, CA, United States of America

Shekher Bulusu