Examples are described herein that relate to a mesh in a switch fabric. The mesh can include one or more buses that permit operations (e.g., read, write, or responses) to continue in the same direction, drop off to a memory, drop off a bus to permit another operation to use the bus, or receive operations that are changing direction. A latency estimate can be determined at least for operations that drop off from a bus to permit another operation to use the bus or receive and channel operations that are changing direction. An operation with a highest latency estimate (e.g., time of traversing a mesh) can be permitted to use the bus, even causing another operation, that is not to change direction, to drop off the bus and re-enter later.

The present invention relates to a method for removing data frame redundancy in a network environment and a device for carrying out the method, which can comprise: a data frame reception step of receiving a first data frame from an adjacent node; and a redundant frame determination step of determining whether a reception completion indicator of a second data frame having the same identification information as the first data frame exists, on the basis of a preset redundancy check table, and processing the first data frame according to the determination result. Disclosed is the data frame redundancy removal method, which deletes the first data frame when the reception completion indicator of the second data frame having the same identification information as the first data frame exists in the redundancy check table.

A method including receiving at a buffer at least a portion of an incoming frame, holding in the buffer the at least a portion of the frame received at the buffer, keeping in the buffer the at least a portion of the frame held in the buffer after transmission of the incoming frame by transmission circuitry responsive to receiving a signal at the buffer indicating that the at least a portion of a frame held in the buffer should be kept, and clearing from the buffer the at least a portion of a frame held in the buffer responsive to receiving a signal to the buffer indicating that the at least a portion of the frame held in the buffer should be cleared. Related methods and apparatus are also described.

A method including receiving at a buffer at least a portion of an incoming frame, holding in the buffer the at least a portion of the frame received at the buffer, keeping in the buffer the at least a portion of the frame held in the buffer after transmission of the incoming frame by transmission circuitry responsive to receiving a signal at the buffer indicating that the at least a portion of a frame held in the buffer should be kept, and clearing from the buffer the at least a portion of a frame held in the buffer responsive to receiving a signal to the buffer indicating that the at least a portion of the frame held in the buffer should be cleared. Related methods and apparatus are also described.

A network device for a communications network includes a port configured to transmit data to the network at a maximum transmit data rate. The device also includes a transmit buffer configured to buffer data units that are ready for transmission to the network, and a packet buffer configured to buffer data units before the data units are ready for transmission. The packet buffer is configured to output data units at a maximum packet buffer transmission rate faster than the maximum transmit data rate. The device includes a rate controller configured to control a transmission rate of data from the packet buffer to the transmit buffer so that averaged over a period, the transmission rate from the packet buffer to the transmit buffer is at most equal to the maximum transmit data rate, while allowing the transmission rate, at one or more time intervals, to exceed the maximum transmit data rate.

In one embodiment, a method comprises identifying, by a path computation element, essential parent devices from a nonstoring destination oriented directed acyclic graph (DODAG) topology as dominating set members belonging to a dominating set; receiving, by the path computation element, an advertisement message specifying a first dominating set member having reachability to a second dominating set member, the reachability distinct from the nonstoring DODAG topology; and generating, by the path computation element based on the advertisement message, an optimized path for reaching a destination network device in the nonstoring DODAG topology via a selected sequence of dominating set members, the optimized path providing cut-through optimization across the nonstoring DODAG topology.

A processing device includes an internal transmitter to receive packets and to forward those packets across a link to an external receiver external to the processing device. The internal transmitter is to receive a portion of a packet and to begin transmitting the portion across the link to the external receiver before the entire overall packet, of which the portion is a part, is received and validated. For a packet determined to have an error, the internal transmitter does not resend the overall packet across the link even if a message is received from the external receiver to resend the overall packet.

A network device for a communications network includes a port configured to transmit data to the network at a maximum transmit data rate. The device also includes a transmit buffer configured to buffer data units that are ready for transmission to the network, and a packet buffer configured to buffer data units before the data units are ready for transmission. The packet buffer is configured to output data units at a maximum packet buffer transmission rate faster than the maximum transmit data rate. The device includes a rate controller configured to control a transmission rate of data from the packet buffer to the transmit buffer so that averaged over a period, the transmission rate from the packet buffer to the transmit buffer is at most equal to the maximum transmit data rate, while allowing the transmission rate, at one or more time intervals, to exceed the maximum transmit data rate.

A transfer device includes an output-port decision unit to decide, on the basis of storage information stored in a frame input, an output port from which the frame is output from among a plurality of ports, an allocation unit to associate an input port to which the frame is input with an output port from which a frame which is transferred by a cut-through method is output on a one-to-one basis, and allocate a first frame to a first pathway transferring by the cut-through method and allocate a second frame to a second pathway transferring by a store-and-forward method on the basis of type information of an input port to which a frame has been input, class information of the frame, and the output port decided by the output-port decision unit, and an IET-output control unit to output the first frame from the output port, decide whether to divide the second frame on the basis of the class information of the second frame, and output the second frame from the output port on the basis of decision. Therefore, the transfer device can realize an IET low-latency transfer function by control simpler than that in the conventional transfer devices.

Technologies are provided for identifying a source of errors within a computer network that uses cut-through forwarding of network packets. For example, inbound network packets can be received by network devices configured to perform cut-through forwarding. Once the network packets are received, they are processed using cut-through forwarding. If any packet errors are detected, error data associated with the detected errors are stored by the network devices. The error data is transmitted to a monitoring service that uses the error data to create a model of a flow of the errors through the network and to identify a source of the errors. In at least some embodiments, a topology of the network is used by the monitoring service to create the model of the packet error flow.