Abstract: A switching network includes first, second and third switches coupled for communication, such that the first and third switches communicate data traffic via the second switch. The first switch is operable to request transmission credits from the third switch, receive the transmission credits from the third switch and perform transmission of data traffic in reference to the transmission credits. The third switch is operable to receive the request for transmission credits from the first switch, generate the transmission credits and transmit the transmission credits to the first switch via the second switch. The second switch is operable to modify the transmission credits transmitted by the third switch prior to receipt of the transmission credits at the first switch.

Abstract: A switch of a data network implements both a bridge and a virtual bridge. In response to receipt of a data frame by the switch from an external link, the switch performs a lookup in a data structure using a source media access control (SMAC) address specified by the data frame. The switch determines if the external link is configured in a link aggregation group (LAG) and if the SMAC address is newly learned. In response to a determination that the external link is configured in a LAG and the SMAC address is newly learned, the switch associates the SMAC with the virtual bridge and communicates the association to a plurality of bridges in the data network.

Abstract: A switching network has a plurality of switches including at least a switch and a managing master switch. At the managing master switch, a first capability vector (CV) is received from the switch. The managing master switch determines whether the first CV is compatible with at least a second CV in a network membership data structure that records CVs of multiple switches in the switching network. In response to detecting an incompatibility, the managing master switch initiates an image update to an image of the switch. In response to a failure of the image update at the switch, the switch boots utilizing a mini-DC module that reestablishes communication between the switch with the managing master switch and retries the image update.

Abstract: The mode of operation in which a port is configured to operate may be selected so that the manner in which the port will interpret a loss of signal on a receive fiber may be specified. In an immediate mode, the port will interpret a loss of signal on a receive fiber as an indication of a fault on the transmit fiber (or interfaces associated with the transmit fiber) and will immediately shut its transmit interface down. In a multiple cycle detection mode, the port will not immediately interpret a loss of signal on a receive fiber as an indication of a fault on the transmit fiber, but rather will begin monitoring the receive fiber to look for a specified loss of signal pattern on the receive fiber. In this mode the port will interpret a repetitive loss of signal on the receive fiber as an indication of a fault on the transmit fiber. By providing a mode selector, the manner in which the ports are configured to operate may be adjusted individually, as a group, or globally.

Abstract: A diagnostic system provides identification of symptoms in a distributed network and an engine for providing recommended rectification of error sources that correspond to the symptoms. The distributed network may be accessed for current statistics. Symptoms may be identified that correspond to the current statistics. A recommended course of action for the distributed network may be provided based on a predetermined list of courses of actions that correspond to rectifying the performance in the error sources.

Abstract: Port mirroring in a clustered network may be performed between a local switch and a remote switch. A port in the remote switch may be designated a mirrored port where data traffic passing there through can be copied and sent to a mirror-to-port on the local switch. In a virtual local area network (VLAN) environment, data frames of the copied traffic may include a VLAN header identifying the local switch so that routing of the data frames through the network may direct the data frames for monitoring at the local switch.

Abstract: A switching network includes an upper tier and a lower tier including a plurality of lower tier entities. A master switch in the upper tier, which has a plurality of ports each coupled to a respective lower tier entity, implements on each of the ports a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier entity coupled to that port. Data traffic communicated between the master switch and RPIs is queued within virtual ports that correspond to the RPIs on lower tier entities with which the data traffic is communicated. The master switch enforces priority-based flow control (PFC) on data traffic of a given virtual port by transmitting, to a lower tier entity on which a corresponding RPI resides, a PFC data frame specifying priorities for at least two different classes of data traffic communicated by the particular RPI.

Abstract: A switching network includes an upper tier and a lower tier including a plurality of lower tier entities. A master switch in the upper tier, which has a plurality of ports each coupled to a respective lower tier entity, implements on each of the ports a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier entity coupled to that port. Data traffic communicated between the master switch and RPIs is queued within virtual ports that correspond to the RPIs on lower tier entities with which the data traffic is communicated. The master switch enforces priority-based flow control (PFC) on data traffic of a given virtual port by transmitting, to a lower tier entity on which a corresponding RPI resides, a PFC data frame specifying priorities for at least two different classes of data traffic communicated by the particular RPI.

Abstract: A distributed device architecture includes a master device and one or more member devices. A simple network management protocol (SNMP) agent of a master device receives an SNMP request from a managing device. Where the SNMP request pertains to a given member device, and where the SNMP request requires involvement of the given member device to fulfill the SNMP request, the master device generates a non-SNMP request corresponding to the SNMP request and transmits the non-SNMP request to the given member device. A non-SNMP agent of the given member device processes the non-SNMP request and transmits processing results back to the master device. The master device generates an SNMP response corresponding to the processing results, and the SNMP agent of the master device transmits the SNMP response back to the managing device.

Abstract: A switching network includes first, second and third switches coupled for communication, such that the first and third switches communicate data traffic via the second switch. The first switch is operable to request transmission credits from the third switch, receive the transmission credits from the third switch and perform transmission of data traffic in reference to the transmission credits. The third switch is operable to receive the request for transmission credits from the first switch, generate the transmission credits and transmit the transmission credits to the first switch via the second switch. The second switch is operable to modify the transmission credits transmitted by the third switch prior to receipt of the transmission credits at the first switch.

Abstract: A switch for a switching network includes a plurality of ports for communicating data traffic and a switch controller that controls switching between the plurality of ports. The switch controller selects a forwarding path for the data traffic based on at least topological congestion information for the switching network. In a preferred embodiment, the topological congestion information includes sFlow topological congestion information and the switch controller includes an sFlow client that receives the sFlow topological congestion information from an sFlow controller in the switching network.

Abstract: A switching network has a plurality of switches including at least a switch and a managing master switch. At the managing master switch, a first capability vector (CV) is received from the switch. The managing master switch determines whether the first CV is compatible with at least a second CV in a network membership data structure that records CVs of multiple switches in the switching network. In response to detecting an incompatibility, the managing master switch initiates an image update to an image of the switch. In response to a failure of the image update at the switch, the switch boots utilizing a mini-DC module that reestablishes communication between the switch with the managing master switch and retries the image update.

Abstract: In a switching network, each of a plurality of lower tier entities is coupled to each of multiple master switches at an upper tier by a respective one of multiple links. At each of the multiple master switches, a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier are implemented on each of a plurality of ports. Each of the plurality of lower tier entities implements a respective egress port mapping indicating which of its plurality of RPIs transmits egress data traffic through each of its multiple links to the multiple master switches. In response to failure of one of the multiple links coupling a particular lower tier entity to a particular master switch, the particular lower tier entity updates its egress port mapping to redirect egress data traffic to another of the multiple master switches without packet dropping.

Abstract: In a switching network, each of a plurality of lower tier entities is coupled to each of multiple master switches at an upper tier by a respective one of multiple links. At each of the multiple master switches, a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier are implemented on each of a plurality of ports. Each of the plurality of lower tier entities implements a respective egress port mapping indicating which of its plurality of RPIs transmits egress data traffic through each of its multiple links to the multiple master switches. In response to failure of one of the multiple links coupling a particular lower tier entity to a particular master switch, the particular lower tier entity updates its egress port mapping to redirect egress data traffic to another of the multiple master switches without packet dropping.

Abstract: A switching network has a plurality of switches including at least a switch and a managing master switch. At the managing master switch, a first capability vector (CV) is received from the switch. The managing master switch determines whether the first CV is compatible with at least a second CV in a network membership data structure that records CVs of multiple switches in the switching network. In response to detecting an incompatibility, the managing master switch initiates an image update to an image of the switch. In response to a failure of the image update at the switch, the switch boots utilizing a mini-DC module that reestablishes communication between the switch with the managing master switch and retries the image update.

Abstract: A switching network includes an upper tier including a master switch and a lower tier including a plurality of lower tier entities. The master switch includes a plurality of ports each coupled to a respective one of the plurality of lower tier entities. Each port includes a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier entity coupled to that port. Each port also includes a receive interface that, responsive to data traffic from a particular lower tier entity, queues the data traffic to the virtual port that corresponds to the RPI on the particular lower tier entity that was the source of the data traffic. The master switch further includes a switch controller that switches data traffic from the virtual port to an egress port from which the data traffic is forwarded.

Abstract: A switching network includes an upper tier having a master switch and a lower tier including a plurality of lower tier entities. The master switch, which has a plurality of ports each coupled to a respective lower tier entity, implements on each of the ports a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier entity coupled to that port. Data traffic communicated between the master switch and RPIs is queued within virtual ports that correspond to the RPIs with which the data traffic is communicated. The master switch applies data handling to the data traffic in accordance with a control policy based at least upon the virtual port in which the data traffic is queued, such that the master switch applies different policies to data traffic queued to two virtual ports on the same port of the master switch.

Abstract: Each of first and second bridges of a data network having respective links to an external node implement a network bridge component that forwards traffic inside the data network and a virtual bridge component that forwards traffic outside of the data network. A virtual bridge is formed including the virtual bridge components of the first and second bridges and an interswitch link (ISL) between the virtual bridge components of the first and second bridges. Data frames are communicated with each of multiple external network nodes outside the data network via a respective one of multiple link aggregation groups all commonly supported by the virtual bridge.

Abstract: A switch of a data network implements both a bridge and a virtual bridge. In response to receipt of a data frame by the switch from an external link, the switch performs a lookup in a data structure using a source media access control (SMAC) address specified by the data frame. The switch determines if the external link is configured in a link aggregation group (LAG) and if the SMAC address is newly learned. In response to a determination that the external link is configured in a LAG and the SMAC address is newly learned, the switch associates the SMAC with the virtual bridge and communicates the association to a plurality of bridges in the data network.

Abstract: Each of first and second bridges of a data network having respective external links to an external node implement a network bridge component that forwards traffic inside the network and a virtual bridge component that forwards traffic outside of the network. A virtual bridge is formed including the virtual bridge components of the first and second bridges and an interswitch link (ISL) between the virtual bridge components of the first and second bridges. Data frames are redirected via the ISL in response to a link-down condition of one of the external links.