Abstract: A method and apparatus for measuring the timing difference between physical IMA links and for delivering time difference to the IMA layer. The invention includes obtaining a first data value for use as a reference, obtaining a second data value, processing the first and second data values to obtain an indication of frequency difference and determining a number of stuffing cells to be added to an ATM link based upon the indication of frequency difference.

Abstract: The present invention relates to a method and apparatus for testing components in ATM networks utilizing loop-back based ATM layer testing. The method and apparatus utilize interfaces and identifier codes to send and loop-back test cells along portions of virtual channels to test the virtual channels.

Abstract: The present invention relates to an ATM-PON system realizing an access network of FTTC/H(fiber-to-the-curb/home), more particularly, to an optical network unit function processing apparatus in ATM-PON system linked directly to a plurality of subscriber's lines.

Abstract: In a communication system for transmitting and receiving communication frames between a plurality of communication terminals and a server, a control frame which is indicative of control information necessary for communication between the communication terminals and the server and whose size is smaller than the size of the communication frame is transferred being included in a preamble portion of each communication frame and when no communication frame to be transmitted exists, the control frame is transferred as an independent frame.

Abstract: According to a disclosed embodiment, a flow indication counter is incremented each time a data packet is transmitted from a buffer. When the number of data packets transmitted equals or exceeds a threshold number, a flow indication message comprising the buffer window size is generated and transmitted to the base station controller. Further, flow indication messages can be generated and transmitted every threshold time interval, independently of the number of data packets transmitted to ensure that flow indication messages are sent at least every preset time interval. Moreover, a system for flow control can be constructed comprising a flow indication counter module configured to provide an updated number of data packets transmitted. The system further comprises a window size monitoring module which determines the buffer window size and a message generating module which generates a flow indication message comprising the buffer window size.

Abstract: In a policing apparatus, a cell receiving unit receives cells to temporarily store the received cells and performs a policing violation process to each of the received cells as a reception cell based on a result of policing violation determination to the reception cell. A cell data storing section has a cell data storing table for circularly storing a cell identification data of the reception cell, and a subscriber data storing section has a subscriber data storing table for storing a management data necessary for the policing violation determination, for every cell identification data. A control unit refers to the subscriber data storing table based on the cell identification data of the reception cell each time the reception cell is received to read out the management data, and performs the policing violation determination to the reception cell based on the read out management data and an address pointer value for the reception cell.

Abstract: In a network including a plurality of exchanges, an exchange at an order request destination is specified from a maintenance terminal of an exchange at an order request source, and an order for performing maintenance and management is input. The OAM cell including the order is generated and transmitted as an ODR-OAM cell. The exchange specified with the ODR-OAM cell performs the process according to the order, and transmits the result of the process to the order request source by using an ODR-OAM cell. The order request source receives the result of the process, and maintains and manages the network. OAM cells in an ATM network are defined as OAM cells for a file update process. The first cell is an FVC-OAM cell for checking the version number of the system file of an exchange at an opposing exchange. The second cell is an FSP-OAM cell for preparing the start of the file update process. The third cell is an FIS-OAM cell for dividing a new file used for an update and carrying the file.

Abstract: Described is a method extending the OAM functionality in the RPR networks through a new OAM loopback procedure of request-reply type together with the definition of a new RPR OAM loopback frame. The OAM loopback function allows any RPR station to check the reachability of another RPR station. It is not necessary to stop any data traffic communication on the network in order to perform this function.

Abstract: An access server and a DSLAM are continuously connected by a PVC. The access server and the DSLAM manage an unused ATM VC within the PVC while making a communication with an idle VC indication cell which is an OAM cell. The DSLAM allocates the unused ATM VC by communicating with the access server based on a call originating request issued from a modem.

Abstract: In a node (14) which is for use in an ATM (asynchronous transfer mode) network and which is supplied with user cells, the node includes a failure detecting section (11) for detecting a failure which is occurred in the ATM network such that no user cell is supplied to the node. The node further includes a band detecting section (12) for detecting, as a detected band, a transmission path band used in transferring the user cells immediately before occurrence of the failure. Connected to the failure detecting section and the band detecting section, a producing section (13) produces, when the failure detecting means detects the failure, OAM (Operation: Administration and Maintenance) cells at a production rate increased within a range such that the detected band is not exceeded. The OAM cells are for use in transferring information indicative of occurrence of the failure.

Abstract: A method of measuring the Round Trip Time (RTT) if a Virtual Circuit (VC) utilizing the Traffic Management mechanism of ATM. The RTT is measured in real time individually for each new opened VC and/or for existing VC routes in the network. In addition, the RTT measurement method of the present invention can be used to determine the CRM parameter for a VC on an end to end basis, e.g., user to user or LEC to LEC, so as to achieve better performance of the network. The invention comprises a first embodiment that utilizes the SN field of a RM cell in measuring the RTT and a second embodiment that does not utilize the SN field in measuring the RTT. In addition, an application of the method is presented in determining the CRM parameter within the TM descriptor.

Abstract: In an ATM communication monitoring device which monitors by using a monitor timer, a connection ID generator generates connection ID's, and an OAM cell generator queues connection information of an OAM cell to be generated corresponding to the connection ID's at a predetermined cycle where the fundamental cycle signal is counted and generates the OAM cell, in order to increase operation time accuracy of the monitor timer and reduce the hardware cost. Also, a counter counts the fundamental cycle signal, and an OAM cell generator queues connection information of an OAM cell corresponding to the connection ID's at a predetermined cycle based on a value of the counter and generates the OAM cell.