Abstract: A method of discovering a device in a communication network having multiple interconnected nodes includes continuously monitoring, by a device to be discovered, any IP packets sent by a discoverer. The method further includes transmitting, by the discoverer, an IP packet destined for a downstream device and receiving, by the device to be discovered, the IP packet. The method further includes determining, by the device to be discovered, whether the IP packet is intended for the device to be discovered. If the IP packet is not intended for the device to be discovered, retransmitting, by the device to be discovered, the IP packet to the downstream device via an egress port of the device to be discovered.

Abstract: A system for efficient routing of an OAM) frame in an Ethernet switch receives an OAM frame at a first port; building a first classification key dependent on an OAM frame header; classifies in a context of the first port to create a first classification; resolves action dependent on the first classification; modifies the first classification key to create a second classification key; classifies the frame in a context of the second port to create a second classification; sends the second classification key to an OAM engine coupled to the Ethernet switch for modification into a third classification key; receives the third classification key from the OAM engine; modifies the third classification key into a final classification key; modifies the header of the OAM frame with the final classification key; and sends the modified OAM frame to a switching fabric of the Ethernet switch.

Abstract: In one embodiment, a connection is maintained between a pair of ethernet ports that have circuitry connected in series with the ports and receiving power-over-ethernet (PoE) from one of the ports, by providing a controllable bypass circuit coupled to the pair of ethernet ports in parallel with the circuitry receiving power-over-ethernet, sensing a preselected condition, and opening and closing the bypass circuit in response to the presence or absence of the preselected condition. Power sourcing equipment (PSE) may supply the one of the ports with power over ethernet, and the circuitry may transports data between the pair of ethernet ports. The circuitry may also supply the switch with a control signal in response to the detection of the preselected condition.

Abstract: A method and system are provided for measuring the bandwidth of a network segment between a first location and a second location by generating a plurality of synthetic packets at the first location and marking each generated synthetic packet with a transmission timestamp indicative of a first clock time at which the synthetic packet is generated; transmitting each of the generated synthetic packets to the second location; receiving each synthetic packet at the second location and marking each received synthetic packet with a reception timestamp indicative of a second clock time at which the synthetic packet is received at the second location; calculating an inter-packet delay variation of the network segment based on the transmission timestamp and the reception timestamp of two or more synthetic packets; and deriving an available bandwidth of the network segment based on the calculated inter-packet delay variation.

Abstract: Disclosed herein is technology to reduce latency of frames through a network device supporting various priorities. In an implementation, a method comprises configuring one or more priorities with a preemptive right over other one or more of said plurality of priorities; receiving frames in a sequence, each of the frames having a frame priority comprising of one of said plurality of priorities; queuing the received frames in a predetermined order based on a frame arrival time and the frame priority; transmitting a current frame based on a current frame priority and current frame arrival time; stopping transmission of the current frame when a later frame in the sequence is received that has a later frame priority with preemptive right over the current frame priority; transmitting an invalid frame check sequence; transmitting the later frame; and restarting the transmission of the current frame after transmitting the later frame.

Abstract: Disclosed herein is a method, a computer program product, and a carrier for indicating one-way latency in a data network (N) between a first node (A) and a second node (B), wherein the data network (N) lacks continuous clock synchronization, comprising: a pre-synchronization step, a measuring step, a post-synchronization step, an interpolation step, and generating a latency profile. The present invention also relates to a computer program product incorporating the method, a carrier comprising the computer program product, and a method for indicating server functionality based on the first aspect.

Abstract: A method of determining the presence of a loopback in one or more networks comprises storing information related to a test instance; sending a loopback detection beacon (LPDB) containing information related to the test instance from a port on an originating device; monitoring the port for a predetermined time period to detect LPDBs arriving at the port during the predetermined time period; and determining whether a detected LPDB contains information corresponding to the stored information, to detect the presence of a loopback. The method may determine whether a detected loopback is a port loopback, a tunnel loopback or a service loopback. The stored information related to the test instance may be deleted if an LPDB arriving at the port and containing information corresponding to the stored information is not detected within the predetermined time period.

Abstract: A method of simplifying the implementation of Synchronous Ethernet on an Ethernet device having a first port and a second port device using a predetermined protocol and signaling, comprises delivering a master clock from a Synchronous Ethernet system to the first port of the Ethernet device; transmitting the delivered master clock to the second port of the Ethernet device independently of the protocol and signaling of the Ethernet device; and transmitting the master clock from the second port of the Ethernet device to a downstream device that supports Synchronous Ethernet. In one implementation, the Ethernet device has a local clock, and the method synchronizes the local clock to the master clock. In another implementation, the Ethernet device does not have a local clock, and the master clock is transmitted from the second port of the Ethernet device to the downstream device without any synchronizing operation at the Ethernet device.

Abstract: A SOAM virtualization system for a network having at least first and second maintenance entities coupled to each other comprises a network controller coupled to at least one of the first and second maintenance entities through a tunnel for virtualizing a SOAM network function on the at least one of the first and second maintenance entities to which the network controller is coupled. The network controller may be coupled to the first and second maintenance entities through first and second tunnels, respectively. The first maintenance entity may an originator device, and the second maintenance entity may be a destination device, with the network controller virtualizing the SOAM network function on both devices. The network controller may send a packet containing a tunnel header and a SOAM frame via the first tunnel to the originator device, which then sends the packet containing the SOAM frame to the destination device.

Abstract: Technology is disclosed herein for monitoring a network path. In an implementation, a device on a network path obtains a burst capacity of the network path, determines a round trip time associated with a burst of traffic sent over the network path, and determines a predicted throughput of the network path based at least in part on the burst capacity of the network path and the round trip time of the burst of traffic.

Abstract: A system is provided for multicasting an event notification from an event producer to multiple event listeners, where the event producer and event listeners exist within a computer operating system having a user space, a kernel space, a device space, and an event protocol handler located in the kernel space. The system generates an event indication from an event producer located in the user space, kernel space, or device space, and receiving the event indication in the event protocol handler and generating an event notification. The event producer and the event listeners interface with the event protocol handler to send the event indication and receive the event notification. The event listeners may be located in the user space, kernel space, or device space.

Abstract: A method of providing information regarding an Ethernet frame, within the Ethernet preamble of the Ethernet frame, comprises inserting into the Ethernet preamble an inter-line-card header that includes a start control character, a version number, a parity bit, a source port, a destination port, and a forwarding domain entry; and preserving said inter-line-card header, inside of said Ethernet preamble, in a Media Access Control (MAC) sub-layer in said Ethernet frame. The method may include a step of selecting the decoding format for the inter-line-card header corresponding to the version number and/or forwarding other Ethernet frames according to additional forwarding information provided by the forwarding domain entry. The inter-line-card header may be preserved in the MAC sub-layer by keeping the Ethernet preamble at the beginning of an Ethernet frame received over an Ethernet backplane, and passing the combined preamble and associated Ethernet frame to an inter-line-card header processing module.

Abstract: A method for indicating one-way latency in a data network, with continuous clock synchronization, between first and second node having clocks that are not synchronized with each other includes a continuous synchronization session and a measurement session. The method repetitively sends predetermined synchronization messages from the first node to the second node and from the second node to the first node, calculates a round trip time for each message at the first node, updates a synchronization point if the calculated round trip time is smaller than a previously calculated round trip time, stores the updated synchronization points of a synchronization window, and calculates a virtual clock from the updated synchronization points of the synchronization window. The measurement session collects multiple measurements of one-way latency between the first and second nodes using the virtual clock, and generates a latency profile by interpolating the multiple measurements.

Abstract: A system for testing Ethernet paths or links without adversely impacting non-test traffic. The system includes a test traffic generator that includes a scheduler that determines when a new test packet is generated. The test traffic generator includes a packet creator that builds a test packet and a transmitter for transmitting the test packet via the Ethernet path or link. The packet creator sends the test packet to the transmitter. The traffic generator includes a transmit credit block coupled to the transmitter or to the scheduler. The transmit credit block stores an amount of credits representing a number of bytes that are available to transmit and decrements the amount each time a non-test packet is communicated via the Ethernet path or link.

Abstract: A system for out-of-line testing of performance of a network, comprising a multiplexer at an input to the network; a demultiplexer at an output from the network; the multiplexer further comprising a traffic generator to insert synthetic traffic, and a first switch to accept an incoming customer traffic stream and join the incoming customer traffic stream with a synthetic traffic stream to form a total traffic stream, the total traffic stream fed to the input to the network; and the demultiplexer comprising a second switch to receive the total traffic stream from the output of the network, and separate the total traffic stream into the synthetic traffic stream and the customer traffic stream, and a traffic analyzer to analyze the separated synthetic traffic stream.

Abstract: A packet generation and inspection system for monitoring the performance of one or more flows on a packet network comprises a processor and memory coupled to each other and to a network bus. The memory stores instructions to be executed by the processor and data to be modified by the execution of the instructions. A processor-controlled arbiter is coupled with the processor and the network bus, and upon reception of a packet on the bus or prior to transmission of a packet on the bus for one of said flows, the arbiter requests execution by the processor of selected instructions stored in the memory by providing the processor with the address of the selected instructions in the memory. The memory provides the processor with data associated with the selected instructions, and the processor modifies the data upon execution of the selected instructions.

Abstract: A method for accurately measuring one or more network performance statistics during one or more sampling periods comprises processing a received data packet to identify flow information and time of arrival; transmitting the data packet, along with metadata comprising the flow information and the time of arrival, to a sample processing module; replaying the reception of the data packet based on the relative speed of the transmission link and the databus and the time of arrival; incrementing a number of bytes received for the data packet for a first sampling period; starting a second sampling period at a predetermined time and incrementing a number of bytes received for the data packet for the second sampling period, if the replaying is not completed. The number of bytes received for the data packet for the first and second sampling periods are processed into first and second sampling period statistics, respectively.

Abstract: Disclosed herein is a method, a computer program product, and a carrier for indicating one-way latency in a data network (N) between a first node (A) and a second node (B), wherein the data network (N) lacks continuous clock synchronization, comprising: a pre-synchronisation step, a measuring step, a post-synchronisation step, an interpolation step, and generating a latency profile. The present invention also relates to a computer program product incorporating the method, a carrier comprising the computer program product, and a method for indicating server functionality based on the first aspect.

Abstract: A method is disclosed for the collection of performance metrics by establishing service operations administration and maintenance (OAM) sessions between an actuator and a plurality of reflectors in a communication network. Test packets from an actuator simultaneously reach a plurality of reflectors along a test path. Each single test packet results into a plurality of test results, one per reflector, with quasi-synchronous performance metrics to sectionalize a network and more efficiently isolate fault or performance problems without the need for additional test packets to isolate the issue. Another method is disclosed wherein an actuator generates and transmits a plurality of simultaneous test packets, one per NID device, resulting into a plurality of test results, one per reflector, with quasi-synchronous performance metrics to sectionalize a network and more efficiently isolate fault or performance problems without the need for additional test packets to isolate the issue.