Abstract: Techniques are provided for the suppression of reference signal transmissions to enable sensing in cognitive radio communications. In one example, there is provided a method, operable by a network entity (e.g., evolved Node B), that may involve communicating with another network entity to determine parameters of a quiet period, the parameters comprising at least one of when the quiet period occurs and duration of the quiet period. The method may involve transmitting a reference signal in a first channel exclusively during a first plurality of subframes of a first frame period, wherein the first frame period further includes a quiet period during which no signals are transmitted, and performing during the quiet period a sensing operation with respect to the first channel.

Abstract: An apparatus and method are described for discovering a configured tunnel between nodes on a path in a data communications network. In an embodiment, an apparatus is arranged to remotely access at least one node on the path, identify whether a tunnel is configured on the access node and, if so, identify whether the identified tunnel has a fault.

Abstract: The association device obtained from an association request issued by a terminal both an identifier of said terminal and the address of a gateway via which the terminal is connected to the network. The device also obtains a second gateway address from the source address of an access request issued by another terminal for making a connection to the user account. The terminal and the user account are associated when the two gateway addresses are equal.

Abstract: A communication control method and a communication device are provided by which the communication quality of an upper layer can be ensured at a lower layer. The communication device that is connected to another communication device to constitute a network, includes a upper-layer quality detection section (105, 106) that detects quality information of communication traffic of an upper layer higher than a predetermined layer, and a lower-layer control section (107) that controls communication of the predetermined layer based on the quality information on the upper layer so as to guarantee communication quality of the upper layer. When a plurality of paths passing through the communication device coexist, the lower-layer control section can share the quality information of the upper layer of these paths in respect to path control and further can switch the route of a path other than a path in which the communication quality of the upper layer has degraded.

Abstract: A method for transferring test messages includes a Network Element (NE) A and NE B negotiating and determining a logical channel type. The Link Management Protocol (LMP) entity of NE A constructs a test message packet which includes the local Ethernet data interface ID, and transfers the test message packet to the local packet control module. The packet control module of NE A encapsulates the test message packet according to the logical channel type determined through negotiation, and transfers the encapsulated packet to the local transmitting interface. The receiving interface of NE B identifies and receives the packet. The packet control module of NE B obtains the packet from the local receiving interface and then encapsulates the packet. Next the packet control module of NE B transfers the test message packet obtained after decapsulation to the local LMP entity.

Abstract: An aspect of the embodiments related to a packet transmission apparatus includes a user identification unit for identifying the user of an input user flow upon input of the user flow containing communication packets and maintenance packets, a maintenance packet extraction unit for extracting the maintenance packets from the user flow of the user identified by the user identification unit, a maintenance packet output control unit for controlling the transparent output of the maintenance packets extracted by the maintenance packet extraction unit based on the monitor rate setting, and a control unit for monitoring and controlling the user flow of the particular user based on the maintenance packets of the user transparently output by the maintenance packet output control unit.

Abstract: A method and apparatus for testing network devices maintains state data in a memory corresponding to a current status for each one of a plurality of connections. Received and transmitted segment identifiers relate each received segment to one of the connections. Each received and transmitted segment is processed and advanced according to a TCP standard and the state data for each segment is updated in the memory. Statistics are collected for each segment as they are processed.

Abstract: A diagnostic tool for identifying priority errors within a data network is realized using a priority trace data packet. The priority trace data packet is originated at an originating node of interest and terminated at a terminating node of interest. At various intermediate network nodes along the data path between the originating and terminating nodes, the priority trace packet is inspected to determine the current priority value of the priority trace packet. The current priority value is stored in a priority trace field that can be analyzed by a network management node to identify one or more sources of priority errors.

Abstract: The present invention relates to the field of mobile communication technologies, and discloses a method, an apparatus, and a system for optimizing a tracking area, and a method, an apparatus, and a system for updating a tracking area. The method for optimizing a tracking area includes the following steps: an Operation, Administration and Maintenance entity obtains an optimization threshold, and performs a tracking area optimization according to the optimization threshold. With the present invention, the Operation, Administration and Maintenance entity can optimize the tracking area automatically.

Abstract: Methods and devices for logically segmenting an LSP so that OAM DTUs may be used to determine the performance and/or the status of LSP segments. To segment a previously determined LSP, a dedicated subpath (a logical LSP) within that predetermined LSP is defined between two LSRs that are capable of processing OAM DTUs. The source node (source LSR) establishes a logical LSP between itself and the destination node (destination LSR) using an LDP. In doing this, the logical LSP traverses a specific path and transits through specific nodes in that path. The source node then transmits an OAM DTU or any other specialized DTU to the destination node using a label specifically associated with the logical LSP that was established. The characteristic of the specific path traversed by the logical LSP can thus be determined by when, how, and if the specialized DTU is received by the destination node.

Abstract: An Ethernet MAC OAMP Control sublayer is provided for supporting SDH/SONET OAMP standard functionality in Ethernet Networks. In accordance with one embodiment, an Ethernet MAC OAMP Control sublayer is provided for processing Ethernet MAC OAMP Control frames. The MAC OAMP Control sublayer provides support for a MAC OAMP Client to implement all of the SDH/SONET OAMP standard functionality. The MAC OAMP Control frame provides support for SDH/SONET OAMP on Ethernet networks. The Network Equipment can use the MAC OAMP Control frames to communicate with the downstream and upstream Network Equipment about various OAMP events, requests, performance parameters, communications channels, maintenance, and test functionality.

Abstract: A topology aware entity, such as an OSS (Operations Support System), an NMS (Network Management System) or an RM (Resource Manager), associated with an Ethernet network is configured to execute a method for topological location discovery of nodes that are added to the network. According to the method, the topology aware entity receives (step 30) a notification about a new node that has been added to the network. Then, the topology aware entity causes (step 31) an existing node to initiate a path discovery to the new node using an Ethernet Connectivity and Fault Management, CFM, protocol, such as IEE 802.1 ag or ITU-T Y.1731. The topology aware entity receives (step 32) the resulting path data from the existing node and identifies (step 33), based on the path data, a topological position of the new node in the Ethernet network. The method may be embodied as Identify topological position of new program instructions stored on a computer-readable medium.

Abstract: A system and method in accordance with exemplary embodiments may include receiving, from a user system, one or more protocol analysis request messages via a network, transmitting, to one or more multipurpose interface devices, one or more control signals based on the one or more protocol analysis request messages, receiving, from the one or more multipurpose interface devices, protocol analysis data associated with data traffic transmitted on one or more test networks in response to the transmitted control signals, and outputting, to the user system, the protocol analysis data via the network.

Abstract: The present invention discloses a method for checking MA integrity, including: creating an MEP a; determining, by an MEP c in an MA, whether an MEP b with the same source port information as the MEP a exists in the MA; if there exists an MEP b with the same source port information as the MEP a in the MA, no isolated and unmated MEP exists in the MA; if an MEP b with the same source information as the MEP a does not exist in the MA, an isolated MEP exists in the MA. The present invention also discloses an apparatus for checking an MA integrity and a method and an apparatus for adding an MEP. The present invention enables a user to know whether an MA is integral and ensures MA integrity.

Abstract: A network environment including a provider network coupled to a first customer network site via a first access link and to a second customer network site via a second access link. The provider network is operable with the IEEE 802.1ag standard for propagating a remote link fault condition via an Ethernet Alarm Indication and Suppression (AIS) frame or a Continuity Check (CC) frame, which is translated into a locally compliant non-IEEE 802.1ag error delivery condition so that a management entity associated with the first customer network site is appropriately alerted.

Abstract: A Maintenance Association and corresponding method for configuring maintenance entities for Ethernet Tree (E-Tree) type service instances. A root MEP communicates with each of a plurality of leaf MEPs. Remote MEP state machine instances are activated within the root MEP for each of the plurality of leaf MEPs. Within each leaf MEP, however, only the remote MEP state machine instance for the root MEP is activated while leaving the remote MEP state machine instances for all other leaf MEPs in an inactive state in which Connectivity Check Messages (CCMs) are not exchanged.

Abstract: Ethernet OAM MEPs are automatically configured in a link state protocol controlled Ethernet network. A node operating in the link state protocol controlled Ethernet network receives a Link State PDU (LSP) containing a TLV having a MEP associated with the Ethernet MAC node ID of a second node in the link state protocol controlled Ethernet network, where the path between the first and second node includes a plurality of links. The node updates a forwarding table to indicate an association between the MEP ID and a Ethernet MAC node ID of the second node. An Ethernet OAM maintenance endpoint is produced in a link state protocol controlled Ethernet network by hashing a Sys-ID to produce a MEP; storing the MEP in a TLV; and forwarding the TLV over the link state protocol controlled Ethernet network in an LSP.

Abstract: A system and method for collecting network performance information from a packet network. The method may include requesting network performance information from network communications devices on a packet network, collecting the network performance information from the network communications devices, where the network performance information is indicative of communications of real-time content and non-real-time content, and storing the network performance information in a configuration distinguishing the network performance information indicative of communications of real-time content.

Abstract: A system is provided for network outage assessment. An outage tool retrieves a scheduled site list from a network management interface for a data network. The scheduled site list specifies sites associated with the network management interface that are scheduled to be active and sites that are scheduled to be inactive. The outage tool retrieves communication site lists from gateways associated with the network management interface. Each of the communication site lists is associated with a corresponding gateway and specifies sites that are in communication with the corresponding gateway. The outage tool identifies sites that are listed as the sites associated that are scheduled to be active and absent from the sites that are in communication with the corresponding gateway as a list of outage sites. The outage tool outputs outage site data based on the list of outage sites to the user interface to enable a management action.

Abstract: On a first network element in a radio access network (RAN), supporting operations, management and administration (OAM) between network elements that support Ethernet in the first mile (EFM) and network elements that support connectivity fault management (CFM) in the radio access network by receiving an EFM message from a second network element that supports EFM, wherein the second network element is in the RAN and wherein the EFM message includes OAM data; converting the OAM data from the EFM message into a sub-type-length-value (sub-TLV) of a CFM message; and transmitting the CFM message including the OAM data in the sub-TLV to a third network element that supports CFM, wherein the third network element is in the RAN, whereby an end-to-end OAM sublayer is provided in the RAN by conversion of OAM data from EFM to CFM.

Abstract: A method for notifying a packet destination that includes receiving a packet by a network interface card (NIC), where the packet destination is a destination of the packet, classifying the packet, forwarding the packet to one of a plurality of receive rings on the NIC, determining whether the one of the plurality of receive rings comprises space to store the packet, dropping the packet if the receive ring does not comprise the space to store the packet, and sending a notification message to the packet destination, where the notification message indicates that the packet was dropped by the receive ring.

Abstract: The invention provides a PVC switching control method for an ATM communication network which allows high speed changeover of a connection upon occurrence of/release from a trouble and is superior in reliability and maintenance facility and simple in control. A master PVC connection and an OAM connection are set between two ATM exchanges, and a bypassing PVC connection and an OAM connection prepared in advance for bypassing are set between the two ATM exchanges. If occurrence of/release from a trouble with and of the master PVC connection is recognized by the ATM exchanges using an OAM function, then the operative PVC connection is switched between the master PVC connection and the bypassing PVC connection.

Abstract: Methods and devices for logically segmenting an LSP so that OAM DTUs may be used to determine the performance and/or the status of LSP segments. To segment a previously determined LSP, a dedicated subpath (a logical LSP) within that predetermined LSP is defined between two LSRs that are capable of processing OAM DTUs. The source node (source LSR) establishes a logical LSP between itself and the destination node (destination LSR) using an LDP. In doing this, the logical LSP traverses a specific path and transits through specific nodes in that path. The source node then transmits an OAM DTU or any other specialized DTU to the destination node using a label specifically associated with the logical LSP that was established. The characteristic of the specific path traversed by the logical LSP can thus be determined by when, how, and if the specialized DTU is received by the destination node.

Abstract: A method for activation of circuits in telecommunications networks comprises a first step in which circuits are preplanned in the network and local definition data are distributed to network members (NE) for connection of sections of the preplanned circuits. In a second step, when it is desired to activate a preplanned circuit, activation messages for the connection of sections making up the preplanned circuit to be activated and which are defined by the data previously distributed to the network members are propagated in the network in cascade among the network members affected by the preplanned circuit by means of overhead bytes of the frames circulating in the network. The data are made up of indexed tables defining pairs formed from “next point (TP) to be connected” and “index” to be propagated for the following cross-connection. A network functioning in accordance with the method is also proposed.

Abstract: A network includes an egress node connected to an ingress node via a network path. The egress node is configured to receive, from the ingress node, a group of packets via the network path, where each packet includes an operations, administration, and management (OAM) field appended to the packet, and where the OAM field stores OAM information. The egress node is further configured to read the OAM information from the packets; analyze the OAM information, associated with one or more of the packets, to determine that a network condition exists on the network path; and notify the ingress node that the network condition exists to permit the ingress node to perform a rerouting operation.

Abstract: An example network system includes a layer two (L2) device and a layer three (L3) device. The L2 device includes a control unit is configured to determine a preferred network path from a first L2 network in which the L2 device resides to an intermediate L3 network in which the L3 device resides that couples the first L2 network to a second L2 network having a second L2 device. The control unit includes a management endpoint (MEP) module. The MEP module executes an operations, administration, and management (OAM) protocol to monitor the first L2 network and output an L2 frame in accordance with the OAM protocol to the L3 device to notify the L3 device that it is within the preferred network path. A MEP module of the L3 device executes an OAM protocol that outputs L2 frames to the L2 device indicating the status of the L3 network.

Abstract: A method and apparatus for reducing the number of CC messages transmitted in a provider network. In one embodiment of the invention, a first service provider network element receives CC messages from a first customer network at a first periodicity rate. The first service provider network element stores the received CC messages and reduces the first periodicity rate to create a second periodicity rate that is smaller than the first periodicity rate. The first service provider network element transmits CC messages to a second service provider network element through the provider network at the second periodicity rate. Other methods and apparatus are also described.

Abstract: An Ethernet MAC OAMP Control sublayer is provided for supporting SDH/SONET OAMP standard functionality in Ethernet Networks. In accordance with one embodiment, an Ethernet MAC OAMP Control sublayer is provided for processing Ethernet MAC OAMP Control frames. The MAC OAMP Control sublayer provides support for a MAC OAMP Client to implement all of the SDH/SONET OAMP standard functionality. The MAC OAMP Control frame provides support for SDH/SONET OAMP on Ethernet networks. The Network Equipment can use the MAC OAMP Control frames to communicate with the downstream and upstream Network Equipment about various OAMP events, requests, performance parameters, communications channels, maintenance, and test functionality.

Abstract: A technique controls the capacity of a virtual concatenation group (VCG) carried on a SONET path of a data network. Efficient control of VCG capacity is provided by emulating aspects of a Link Capacity Adjustment Scheme (LCAS) protocol in software. A hardware poller facility is employed to manage the status and state of the VCG, as well as members belonging to the VCG. The hardware poller contains one or more VCG state machines (VSMs) and member state machines (MSMs) configured to maintain the status and states of the VCGs and their members.

Abstract: According to an aspect of an embodiment, an apparatus is transmitting/receiving an OAM frame containing kinds of tests indicating one or more tests for Ethernet-OAM to/from a relay apparatus, storing configuration information to generate a network configuration needed for each of the plurality of tests in a pseudo manner, distinguishing the kind of test contained in the relevant OAM frame and obtaining network information of a network to which the relay apparatus that transmitted the OAM frame belongs and obtaining configuration information corresponding to the obtained network information obtained from the stored configuration information.

Abstract: A method performed on a network element employing Multiprotocol Label Switching (MPLS) to promulgate an alert to each Label Switch Router (LSR) along a Label Switch Path (LSP) by forwarding a labeled packet serving as an alert packet generated by an LSR in the LSP, the method including receiving the labeled packet by the network element from another LSR in the LSP, determining whether the labeled packet is the alert packet by checking a time to live value in an MPLS label header of the labeled packet, determining whether the labeled packet is an operation, administration and maintenance (OAM) packet based on a presence of a generic associated channel label, copying the labeled packet including a label stack of the labeled packet and forwarding the labeled packet to a next LSR in the LSP, whereby the latency in promulgating the alert to each of the LSRs in the LSP is reduced.

Abstract: In general, techniques are described for simultaneously testing connectivity to same or different remote maintenance endpoints of the same maintenance association. Specifically, a network device may include a control unit that simultaneously executes both a first and a second maintenance session. The control unit maintains first and second session identifiers that uniquely identifies the first and second maintenance sessions. The control unit receives via the first maintenance session input that specifies parameters for a maintenance message and generates the maintenance message in accordance with the parameters such that the maintenance message includes the first session identifier. The network device also includes an interface card that forwards the maintenance message to another network device in order to determine connectivity between these two network devices.

Abstract: A Maintenance Association and corresponding method for configuring maintenance entities for Ethernet Tree (E-Tree) type service instances. A root MEP communicates with each of a plurality of leaf MEPs. Remote MEP state machine instances are activated within the root MEP for each of the plurality of leaf MEPs. Within each leaf MEP, however, only the remote MEP state machine instance for the root MEP is activated while leaving the remote MEP state machine instances for all other leaf MEPs in an inactive state in which Connectivity Check Messages (CCMs) are not exchanged.

Abstract: A method and apparatus for a method and apparatus for determining a path supporting a mobile session to identify the underlying transport elements supporting the path. In various embodiments mobile session tracing is implemented within a network such as a Long Term Evolution (LTE) wireless network by determining elements in a path supporting a mobile session of a user equipment (UE) having an specific identifier, such as an IP address or terminal identification number.

Abstract: A packet loss rate detection method, apparatus, and system relating to a Packet Switching Network (PSN) are provided, and the method includes: transmitting, by a transmitting end, data packets and Operation, Administration, and Maintenance (OAM) packets, and writing a counting value of the data packets into the subsequent OAM packets after a time delay, and receiving, by a receiving end, the data packets and the OAM packets, counting a number of the received data packets, and calculating a packet loss rate based on the number of the practically received data packets and the counting value carried in the OAM packets.

Abstract: A method for establishing a monitoring connection associated to a traffic connection established in a network e.g. of MPLS type, the method comprising the steps of: sending a connection establishment message from a first node (B) to a second node (D) of the communication network to establish a monitoring connection (6) between the first and second nodes, wherein the first and second nodes are disposed in a path of the traffic connection and the connection establishment message is sent along the traffic connection path, sending a make-before-break request from the first node (B) to an ingress node (A) of the traffic connection to cause the ingress node to re-establish the traffic connection along the traffic connection path using a make-before-break signaling procedure, at the first node, processing a re-establishment signaling message sent by the ingress node so as to encapsulate the re-established traffic connection (5) into the monitoring connection (6).

Abstract: A method for establishing a traffic connection (5) and an associated monitoring connection (6) in a network (1) e.g. of MPLS type, comprises: sending a first connection establishment message from an ingress node (A) of the traffic connection along a path, wherein the connection establishment message comprises a monitoring connection request designating a first and a second node of the connection path, intercepting the first connection establishment message at the designated first node (B), sending a second connection establishment message from the designated first node for establishing the monitoring connection between the designated first and second nodes (B, D), resuming and completing the establishment of the traffic connection, wherein the traffic connection is encapsulated into the monitoring connection between the designated first and a second nodes of the connection path.

Abstract: Techniques for detecting and suppressing jammers are described. A receiver may perform post-FFT jammer detection and pre-FFT jammer suppression. The receiver may transform an input signal to obtain a frequency-domain signal and may detect for jammers in the input signal based on the frequency-domain signal. The receiver may determine powers of a plurality of carriers based on the frequency-domain signal and may detect for jammers based on peaks in the powers of these carriers. The receiver may filter the input signal (e.g., with a notch filter) to suppress the detected jammers. Alternatively or additionally, the receiver may perform post-FFT jammer detection and post-FFT jammer suppression. The receiver may determine whether jammer is present on each carrier based on data power and channel power for that carrier. The receiver may modify (e.g., zero out or reduce) the frequency-domain signal on carriers with detected jammers.

Abstract: Techniques that assist in processing of failure detection protocol (FDP) packets. Techniques are provided that assist a CPU of a network device in processing incoming FDP packets. In one embodiment, a module is provided in a network device for detecting and flagging the non-receipt of FDP packets by the network device for one or more FDP sessions. In this manner, the task of detecting non-receipt of FDP packets is offloaded from the CPU of the network device. This enables the network device to support newer FDPs with shorter periodic interval requirements.

Abstract: A power-saving wireless network, a packet transmitting method for use in the wireless network, and computer readable medium therefor are provided. The wireless network comprises a PAN coordinator, a receiving node and a transferring node. When the transmitting node has a packet planed to be transmitted to the receiving node which is in a sleep mode, the packet is alternatively transmitted to the PAN coordinator. As soon as the receiving node wakes from the sleep mode, all packets are transmitted to the receiving node from the PAN coordinator. After the packets are all successfully transmitted, the receiving node turns back to the sleep mode subsequently. Thereby, the performance of the wireless network would not be restricted to the sleep period and memory capacity. Thus, the nodes in the wireless network would greatly facilitate saving power.

Abstract: A communications network comprising a plurality of nodes supporting connection-oriented traffic and connectionless traffic, wherein management traffic between the nodes is propagated as connectionless traffic having a common management identifier. Also disclosed is a communications network component comprising logic that supports connection-oriented traffic and Virtual Local Area Network (VLAN)-based connectionless traffic, wherein the logic propagates management messages as VLAN-based connectionless traffic having a unique VLAN identifier (VID). Included is a communications network component comprising at least one processor configured to implement a method comprising provisioning a unique VID for management messages, and selectively propagating management messages with the unique VID.

Abstract: A stateful connection is monitored between wireless communications devices. A first code packet is generated at a first wireless communications device. The first code packet is transmitted from the first wireless communications device to a second o wireless communications device. A determination is made whether a second code packet generated by the second wireless communications device in response to receipt of the first code packet is received by the first wireless communications device within a predetermined time.

Abstract: Various exemplary embodiments relate to a method and related system and machine-readable medium including one or more of the following: receiving, at the MEP, a connectivity fault management (CFM) message; determining whether the CFM message includes an indication specifying a new value for a timeout factor; and when the CFM message includes an indication specifying a new value for the timeout factor, using the new value as the timeout factor. One or more of the following may also be included: when the CFM message does not include an indication specifying a new timeout factor, using a default value as the timeout factor; determining a timeout period using at least the timeout factor; determining whether the timeout period has elapsed since a most recent CFM message was received; and when the timeout period has elapsed since the last CFM message was received, determining that a timeout has occurred.

Abstract: A disclosed communication apparatus of one embodiment of the present disclosure includes a transmitting unit including a counter for counting the number of transmitted data frames and indicating the counted number of the transmitted data frames as a counter value and a scheduler for determining a frame transmission order, and configured to transmit one or more data frames and a monitoring and control frame which includes the counter value; and a generating unit configured to generate the monitoring and control frame. When generating the monitoring and control frame, the generating unit corrects the counter value included in the monitoring and control frame according to the frame transmission order.

Abstract: A method and system for provisioning a Resilient Packet Ring (“RPR”) over a Wavelength Division Multiplexing (“WDM”) network is disclosed. A plurality of stations send data packets to each other over a dual ring fiber optic link. The data packets travel over the dual ring fiber optic link at a unique wavelength to distinguish the different data packets. When one station of the plurality of stations detects a location of a failure in the WDM network, the station identifying the location of the failure either notifies all stations of the plurality of stations of the location of the failure or notifies only the stations of the plurality of stations abutting the location of the failure. If all stations of the plurality of stations are notified of the failure, all stations steer data packets sent towards the location of the failure away from the location of the failure.

Abstract: The present invention relates to a method and a network node for service instance management in telecommunications network. According to the method a plurality of network paths are monitored. A number of network paths form a protection group associated with a service instance or group of service instances. The monitoring of the network paths includes periodic transmission of CCMs on the network paths. To facilitate detection of mismatches related to protection switching, some CCMs include a mismatch information element that specifies traffic status of a working network path and of a protection network path for a set of protection groups. The set of protections groups includes the protection groups which the monitored network path is a member of. A CCM that includes the mismatch information element also includes an indication bit that indicates presence of the mismatch information element in the CCM.

Abstract: It is disclosed a method of monitoring, a Multi-Protocol Label Switching network, a tandem connection of a Label Switched Path. The tandem connection to be monitored has an input node and an output node. The method comprises the following steps: receiving a first Operation Administration Management packet at the input node; and generating a second OAM packet at the input node. According to the invention, the following steps are further performed: a tandem connection header is inserted into the first OAM packet; both the first OAM packet with the tandem connection header and the second OAM packet are sent towards the output node; and the second OAM packet is identified according to the presence or absence of said tandem connection header.

Abstract: Network connectivity management includes monitoring a pathway, wherein the pathway is configured to carry a circuit between multiple networks via a provider core network. A determination is made regarding whether the pathway is experiencing a connectivity issue. When it is determined that the pathway is experiencing a connectivity issue, then a message is generated indicating that the circuit is down.

Abstract: A system and method for propagating fault information in an Ethernet OAM network having multiple levels of OAM domains. An Alarm Indication and Suppression (AIS) frame is generated by a Maintenance Intermediate Point (MIP) node upon detecting a fault condition in a first OAM domain, which is transmitted to one or more Maintenance End Points (MEPs) of the first OAM domain. Upon receiving the AIS frames, the MEP nodes are operable generate another AIS frame for propagating to an adjacent higher level second OAM domain. Responsive to the AIS frame from the lower level first OAM domain, any alarms caused in the second OAM domain due to the fault condition in the first OAM domain are suppressed.

Abstract: Provided are a method and apparatus for transmitting error information between an Ethernet network and a synchronous digital hierarchy (SDH) network. According to the present invention, when an error occurs in the Ethernet network or the SDH network, OAM information is transferred to the opposite network by using a conventional MAC control frame from a linked part of the Ethernet network and the SDH network and thus the EoS network may be efficiently operated and managed. Also, by using standardized MAC control frame, the present invention may be applied to an existing system without additionally changing hardware or defining a new OAM frame.