Abstract: A method of discovering and assigning an IP address to a device to be discovered in a communication network having multiple interconnected nodes includes continuously monitoring, by the device to be discovered, the network for address resolution protocol (ARP) requests. The discoverer node transmits a number of ARP request to the network. The device to be discovered receives the number of ARP requests. The device to be discovered determines whether the number of ARP requests are unanswered by other devices in the network. The device to be discovered answers to the number of ARP requests with an ARP reply to claim an IP address associated with the number of ARP requests. The discoverer node and the device to be discovered exchange a pair of User Datagram Protocol (UDP) packets to complete the detection process.

Abstract: A method of determining the latency of path segments in a communication network that uses multi-bit data packets comprises generating a test packet for use in determining the latency of path segments in the network; transmitting the test packet from a first device coupled to the network; storing in the test packet the time when a preselected bit in the test packet is transmitted from the first device; when the test packet is received by a second device coupled to the network, storing in the second device at least one of (a) the time when a preselected bit in the test packet is received by the second device and (b) the difference between (i) the time when the preselected bit in the test packet is transmitted from the first device and (ii) the time when the test packet is received by the second device.

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 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 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.

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 synchronisation 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: 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 of establishing a service operations administration and maintenance (OAM) session between an originator and a reflector in a communication network includes continuously monitoring, by the reflector, any test packets transmitted by the originator. The originator transmits to the reflector, at a time indicated by a first timestamp, a test packet. The reflector receives the test packet at a time indicated by a second timestamp and generates a unique flow identifier that identifies the reflector. The reflector transmits the test packet to the originator. The reflector assigns a sequence number to the test packet. The originator receives the test packet at a time indicated by a fourth timestamp. The reflector stores the unique flow identifier at least for the duration of the OAM session.

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: 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 method of establishing a service operations administration and maintenance (OAM) session between an originator and a reflector in a communication network includes continuously monitoring, by the reflector, any test packets transmitted by the originator. The originator transmits to the reflector, at a time indicated by a first timestamp, a test packet. The reflector receives the test packet at a time indicated by a second timestamp and generates a unique flow identifier that identifies the reflector. The reflector transmits the test packet to the originator. The reflector assigns a sequence number to the test packet. The originator receives the test packet at a time indicated by a fourth timestamp. The reflector stores the unique flow identifier at least for the duration of the OAM session.

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: 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 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 of automatically detecting the service level agreement settings in an Ethernet virtual circuit (EVC) carrying user packets comprises generating synthetic packets different from the user packets, on a data path in the EVC at a level sufficiently high to saturate the EVC. This accelerates the detection of actual effective values for the Committed Information Rate (CIR) and the Excess Information Rate (EIR) by triggering traffic shaping devices in the data path to enforce the CIR and EIR settings configured for those devices. A plurality of traffic samples are collected from the data path during a sampling period that is long enough to allow the collection of at least two valid traffic samples, where a valid traffic sample is the amount of user packets measured between two consecutive losses of synthetic packets. The CIR and EIR values enforced by the traffic shaping devices are determined from the collected samples.

Abstract: A method is provided for efficiently scheduling timer events within an operating system by allocating a plurality of timers, each of which has an expiry time, to a set of available timer slots. The method defines a timer spread value that denotes the allowed variance of the expiry times of each of the timers, calculates a set of available timer slots for each of the timers based on the timer spread value, and adjusts the expiry times of the timers so as to insert and evenly spread the timers across the set of available timer slots. In one implementation, the set of available timer slots is located in a timer wheel existing within the operating system, and the timer wheel uses a plurality of timer vectors arranged into successively increasing levels, beginning with level zero.

Abstract: A system for negotiating Ethernet link settings between interconnected nodes in a network having an Ethernet protocol stack that includes a PCS sub-layer with an auto-negotiation function. The system comprises connecting an intermediate device coupled between two network nodes via optical or copper interfaces, with the link settings between each node and the connected intermediate device being the same, thereby bypassing the auto-negotiation of the PCS sub-layer in the intermediate device. The intermediate device may transparently send negotiation messages from each node to the other during the link negotiation phase without interacting with those messages. Instead of the intermediate device, a single form pluggable (SFP) device may be connected between the two network nodes via optical or copper interfaces on the network side and via an SFP slot on the device side.

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 is provided for exchanging large amounts of memory within an operating system containing consumer and producer threads located in a user space and a kernel space, by controlling ownership of a plurality of RAM banks shared by multiple processes or threads in a consumer-producer relationship. The method includes sharing at least two RAM banks between a consumer process or thread and a producer process or thread, thereby allowing memory to be exchanged between said consumer process or thread and said producer process or thread, and alternately assigning ownership of a shared RAM bank to either said consumer process or thread or said producer process or thread, thereby allowing said producer process or thread to insert data into said shared RAM bank and said consumer process or thread to access data from said shared RAM bank.

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 synchronisation 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.