Brocade Patent Applications

INGRESS RATE LIMITING

Granted: June 28, 2012
Application Number: 20120163175
A network device monitors the traffic of individual flows through one of its ingress ports and, if the traffic volume exceeds a predetermined threshold, signals for a reduction in data traffic volume transmitted to that ingress port from one or more source devices. Example signals may include without limitation a unicast congestion message sent to the source of a flow, an Explicit Congestion Notification to one or more source devices, and the dropping of packets by the receiving device.…

QUEUE SPEED-UP BY USING MULTIPLE LINKED LISTS

Granted: June 28, 2012
Application Number: 20120163396
One embodiment of the present invention provides a switch that includes a transmission mechanism configured to transmit frames stored in a queue, and a queue management mechanism configured to store frames associated with the queue in a number of sub-queues which allow frames in different sub-queues to be retrieved independently, thereby facilitating parallel processing of the frames stored in the sub-queues.

METHOD AND SYSTEM FOR REMOTE LOAD BALANCING IN HIGH-AVAILABILITY NETWORKS

Granted: June 28, 2012
Application Number: 20120163164
A system is provided for facilitating remote load balancing in a high-availability network. During operation, the system receives a plurality of data frames destined for a destination device, wherein the destination device is coupled to a network via a trunk link, the trunk link coupling the destination device to at least two separate egress switching devices. The system then forwards the data frames via at least two data paths, each of which leads to a respective egress switching…

Repeated Lost Packet Retransmission in a TCP/IP Network

Granted: June 21, 2012
Application Number: 20120155458
Periodically retransmitting of multiply lost TCP/IP packets until either an ACK is received or the timeout finally occurs. By retransmitting the packet more than the once as done with prior art SACK approaches, there is a possibility of not having to wait until the timeout period elapses if one of the other retransmissions successfully transits the network. If the packet is successfully received and acknowledged before the timeout period ends, then the more extensive timeout procedures…

PRIORITY AWARE MAC FLOW CONTROL

Granted: June 14, 2012
Application Number: 20120147747
Solutions are provided that allow a network device to apply flow control on the MAC layer while taking into account the priority of the frame of traffic. This may be accomplished by generating a frame indicating that traffic flow should be paused, while utilizing a new opcode value, or alternatively by utilizing a new type/length value (possibly combined with a new opcode value). A receiving device may then examine the fields of the frame to determine whether it should use priority-based…

Two-Port Memory Implemented With Single-Port Memory Blocks

Granted: June 7, 2012
Application Number: 20120144103
A two-port memory having a read port, a write port and a plurality of identical single-port RAM banks. The capacity of one of the single-port RAM banks is used to resolve collisions between simultaneous read and write accesses to the same single-port RAM bank. A read mapping memory stores instance information that maps logical banks and a spare bank to the single-port RAM banks for read accesses. Similarly, a write mapping memory stores write instance information that maps logical banks…

Content Addressable Memory (CAM) Parity And Error Correction Code (ECC) Protection

Granted: May 3, 2012
Application Number: 20120110411
A memory system including a content addressable memory (CAM) array and a non-CAM array. The non-CAM array, which may share word lines with the CAM array, stores one or more error detection bits associated with each row of the CAM array. A state machine reads entries of the CAM array and corresponding error detection bits of the non-CAM array during idle cycles of the CAM array. Error detection logic identifies errors in the entries read from CAM array (using the retrieved error detection…

Single Virtual Domain Fibre Channel over Ethernet Fabric

Granted: May 3, 2012
Application Number: 20120106957
The entire FCoE fabric is a single virtual domain, even though there may be multiple FCFs and FDFs. The virtual domain is a different Domain_ID than any of the FCFs. In certain embodiments there are multiple FCFs, of which one is selected as the master or designated FCF. The master FCF performs normal fabric configuration in conjunction with the Fibre Channel fabric. The master FCF assigns the virtual domain FC node IDs and controls development of subdomain IDs. Virtual links are…

METHOD AND APPARATUS FOR ESTABLISHING METAZONES ACROSS DISSIMILAR NETWORKS

Granted: May 3, 2012
Application Number: 20120106572
A system and method for creating and enforcing meta-zones that cross the interface between different network protocols are disclosed. In one embodiment, a method of enforcing meta-zones comprises: (a) receiving an Infiniband (IB) packet destined for a Fibre Channel (FC) target device; (b) comparing a partition key in the IB packet to a partition key associated with the FC target device; and (c) converting the IB packet to a FC frame only if the partition keys match. The method may…

NETWORK PACKET LATENCY MEASUREMENT

Granted: May 3, 2012
Application Number: 20120106365
A solution for network packet latency measurement includes, at a network device having a memory, storing a first time value indicating when an ingress port of the network device received a packet. The solution also includes storing a second time value indicating when an egress port of the network device received the packet for transmission towards another network device. The solution also includes storing a difference between the first time value and the second time value.

System And Method For Detecting And Isolating A Remote Loop

Granted: May 3, 2012
Application Number: 20120106361
A system and method are provided for enabling a first network to detect a loop in a second network connected thereto. The first network runs a first instance of a Spanning Tree Protocol and the second network runs either a different instance or no instance. The method includes sending a Remote Loop Detection Packet (“RLDP”) from the ports in bridges of the first network which are connected to the second network. The RLDP includes identifiers such as the source bridge, port and VLAN.…

PATH DIAGNOSIS IN COMMUNICATION NETWORKS

Granted: April 26, 2012
Application Number: 20120099443
One embodiment of the present invention provides a system for mapping all possible paths between a source node and a destination node. During operation, the system receives a management frame, determines all possible next-hop nodes based on a destination address carried in the payload of the management frame. The system then selects one of the next-hop nodes, and modifies payload of the received management frame to include information associated with the next-hop nodes and the selected…

END-TO-END VIRTUALIZATION

Granted: April 26, 2012
Application Number: 20120099602
One embodiment of the present invention provides a system that facilitates end-to-end virtualization. During operation, a network interface residing on an end host sets up a tunnel. The network interface then encapsulates a packet destined to a virtual machine based on a tunneling protocol. By establishing a tunnel that allows a source host to address a remote virtual machine, embodiments of the present invention facilitate end-to-end virtualization.

DOMAIN NAME SYSTEM SECURITY EXTENSIONS (DNSSEC) FOR GLOBAL SERVER LOAD BALANCING

Granted: April 19, 2012
Application Number: 20120096166
Techniques are provided to enable a network device, such as a switch, to perform global server load balancing (GSLB) while operating as a proxy to a domain name system security extensions (DNSSEC)-capable authoritative DNS server. The network device preserves an original signature generated by the DNSSEC-capable authoritative DNS server for a resource record set contained in a DNSSEC reply.

REDUNDANCY LOGIC

Granted: April 19, 2012
Application Number: 20120096310
A network system provides network device having a secondary memory that mirrors the content of a primary memory maintaining data structure parameters entries. The integrity of each data structure parameter entry is tested as the entry is output from the primary memory, such as by using a parity test. If an error is detected in the entry, a corresponding entry from the second memory structure is select for use instead of the entry from the primary memory. The corresponding entries in each…

LINK STATE RELAY FOR PHYSICAL LAYER EMULATION

Granted: April 12, 2012
Application Number: 20120087232
One embodiment of the present invention provides a fault-management system. During operation, the system identifies a failure at a remote location associated with a communication service. The system then determines a local port used for the communication service, and suspends the local port, thereby allowing the failure to be detected by a device coupled to the local port.

DYNAMIC LATENCY-BASED REROUTING

Granted: March 29, 2012
Application Number: 20120075999
A switch creates and dynamically updates a latency map of a network to adjust routing of flows. Further, the network is monitored to detect latency issues and trigger a dynamic adjustment of routing based on the latency map. In this manner, a flow can be routed along a route (i.e., a faster route) that provides less latency than other available routes. The latency map can be generated based on latency probe packets that are issued from and returned to the source switch. By evaluating…

Transmission bandwidth quality of service

Granted: March 29, 2012
Application Number: 20120076149
A bandwidth limiting circuit provides limiting the bandwidth of a group of virtual channels at a transmitting port to a maximum value. A limiting circuit includes a register that is repeatedly incremented with a threshold value, which threshold value is related to the desired maximum bandwidth for the group. The register is decremented by the frame length, in bytes, of the frame transmitted from one of the virtual channels belonging to the group. A comparator enables frame transmission…

Manageability Tools for Lossless Networks

Granted: March 15, 2012
Application Number: 20120063304
Manageability tools are provided for allowing an administrator to have better control over switches in a lossless network of switches. These tools provide the ability to detect slow drain and congestion bottlenecks, detect stuck virtual channels and loss of credits, while hold times on edge ASICs to be different from hold times encore ASICs, and mitigate severe latency bottlenecks.

CONGESTION NOTIFICATION ACROSS MULTIPLE LAYER-2 DOMAINS

Granted: March 15, 2012
Application Number: 20120063316
One embodiment of the present invention provides a congestion notification. During operation, the system receives a congestion notification message with a destination layer-2 address set as the receiving mechanism's layer-2 address. The system modifies a destination layer-2 address, a source layer-2 address, and optionally a VLAN identifier of the congestion notification message, and forwards the modified congestion notification message.