Abstract: The invention distributes the adjacent-router link interfaces of a network node among several logical routers and provides a node-internal interface between at least two of the logical routers. Each logical router is generally assigned a dedicated subset of the adjacent-router link interfaces of the network node. Thereby, the number of adjacencies related to each logical router is reduced, leading to a reduction in the load on the corresponding routing protocol process of each logical router. The routing protocol processes are preferably executed on seperate processors, one for each logical router. This network node implementation is directly scalable by selecting the number of logical routers and properly dividing the adjacencies of the network node among the logical routers.

Abstract: A system and method are disclosed for switching a data flow of information packets intended for paths between a respective sending and receiving entity, the method includes buffering the packets from the paths in a queue; halting a sending entity on congestion of the queue; storing the halt condition in a switch state; noting the individual portions that different of the paths occupy in the queue; halting the sending entity for the path occupying the individually greatest portion of the queue; storing the halted path in a free one of the switch states including storing its bandwidth; successively updating the respective bandwidth of halted paths as the queue is repeatedly congested; determining an older part of the states; and purging the state for a path having the smallest bandwidth in said older part of the states.

Abstract: The present invention relates to an arrangement and a method for echo cancellation wherein only telecommunications traffic (s6) of a downlink (3), for which echo cancellation is performed, passes through an echo canceller function (1′). Traffic (s5) of an uplink (2) is forwarded via a switch (15) to a near end (B) without passing through the echo canceller function (1′). A signal copy (s9) of traffic (s5) of the uplink is created by the switch (15) and directed to the echo canceller function (1′) in order to serve as a base for an estimated echo signal (e′). The estimated echo signal (e′) is subtracted from the traffic (s6) of the downlink, which is input to the echo canceller function (1′), so as to create an output signal (s8), which is substantially free from echo. The invention makes it possible to reduce the processing capacity required in connection with echo cancellation and provides for a decreased delay of traffic of the uplink (2).

Abstract: A connection admission control (CAC) technique for a telecommunications node approximates probability of loss using a log moment generating function and its two partial derivatives of workload on a queue over a time interval. The approximation uses four state variables, which depend on the log moment generating function and its two partial derivatives. The four state variables are: (1) Linear term in approximation to log loss ratio at a working point; (2) the argument of logarithmic term in approximation to log loss ratio at the working point; (3) a buffer limit used at the working point; and (4) a multiplier of imaginary traffic used at the working point. Advantageously, these state variables vary linearly with the traffic, so a new connection can simply add its contributions to them.

Abstract: The invention concerns a telecommunication gateway for processing a data stream in a local chain of process function such as media stream applications (MSAs). The gateway basically includes a bearer control unit (102), a connection coordinator (103), and a resource manager (104) with an associated pool (105) of resources. For a requested connection, the connection coordinator (103) requests a media connection agent (106) and the necessary media stream applications (MSA1-MSA3) from the resource manager (104). The connection agent (106) determines a routing table (107) based on the destination addresses of the requested MSAs, and uses the routing table (107) to route the data stream from an incoming exchange terminal (ET1) to an outgoing exchange terminal (ET2) through the chain of MSAs.

Abstract: A method for mapping a plurality of minicells into a channel structure is disclosed. The channel structure has a plurality of multi-frames with each multi-frame having a plurality of time slots. A start octet is inserted in a first time slot of each multi-frame and the sequence number within the start octet is used to count the number of multi-frames.

Abstract: Method and apparatus for processing data in a multi-processor environment are provided. An application chain is built including at least one application to be performed on the data. The data is received, and program information, e.g., a pointer, is added to the data for identifying a current application in the application chain to be performed on the data. The data is forwarded to an available processor in the multi-processor environment and is processed using the current application identified by the added program information. The processed data is updated with new program information identifying a next application in the application chain to be performed, if any. The processed data is forwarded to an available processor, processed, and updated repeated times until the data is processed by all applications in the application chain.

Abstract: The present invention relates to a coupling node (MG1) for coupling of communications in a telecommunication system, comprising networks (N1, N2) with different signal formats. The coupling node has switching and trunking functions (CP21, CP23) corresponding to the signal formats, and telefunctions, e.g. coders/decoders (F21) and echo cancellers (F22), which the node can couple into a communication by means of a selector (PS1). The functions are supported by printed board assemblies (CB1-CB9) in magazines (SR1), and the printed board assemblies have signal processors (DSP11-DSP13) with access points (SAP11-SAP14). The selector hunts one of the signal processors for handling one of the functions. If the processor has sufficiently free memory space in its data store and in its instruction memory and sufficient processor capacity, this processor is selected. Otherwise a new processor is hunted which is investigated in the same way.

Abstract: A method of indicating the length of a mini cells in a mobile telephony network. Non linear coding of a short fixed length field in the header of the mini cell is described. Either an extension bit method or an extension code method is used to extend the length field so as to increase the number of length values available for coding of the mini cell sizes. The length of a mini cell is indicated in the individual mini cell or is indicated indirectly using a CID/length mapping table. Mini cell sizes are changed during a connection and methods are described for doing this. Cell header reading devices for extracting user information of individual mini cells are described. A mobile telephone network using the cell header reading devices is described.

Abstract: A distributed voice mail system in a network includes a server in a control layer of the network and one or more media gateways in a connectivity layer of the network, wherein the server controls resources in the media gateways to provide distributed voice mail services.

Abstract: In a publically switched telephone network (PSTN), a method and a system for simultaneously and independently multiplexing voice and non-voice data over a single, commonly shared PSTN access line. This is accomplished by packetizing the voice and non-voice data into minicells, and then multiplexing the minicells into a single data stream for transportation across the commonly shared PSTN access line. Once the minicells containing either voice or non-voice data have been transported over the single, commonly shared PSTN access line, the data is simultaneously and independently routed to distinctly different end-users according to the routing information stored in the header portion of each minicell.

Abstract: In a telecommunications network, broken connections can be detected and located through a next hop loopback technique. The next hop loopback technique involves the generation, transmission, and analysis of specialized data packets which attempt to traverse a telecommunications connection, node by node. The failure of a data packet to properly traverse a link can then be used to determine whether a connection is broken, to notify the network management system as to the location of the broken connection, and whether appropriate action is warranted so that the network operator can re-route data around that portion of the network. In addition, the next hop loopback technique can be triggered on an "as needed" basis by the end user, rather than on a periodic basis, thereby conserving network time and resources.

Abstract: In a telecommunications network, segments along a telecommunications connection causing data corruption or data degradation can be detected and precisely identified through a segment performance monitoring technique. The segment performance monitoring technique involves the generation, transmission, and analysis of specialized data packets which traverse a telecommunications connection node by node. At each node, a value for one or more segment performance characterization factors is accumulated based upon a predefined block of user-assigned data packets. Degradation of the data caused by any segment along the telecommunications connection can be determined, in part, by comparing the value for the one or more segment performance characterization factors to one or more performance characterization factor values generated by a source node.

Abstract: In a telecommunication system that employs asynchronous transfer mode (ATM) and minicells to transport communication data, accurate minicell header information dramatically improves the ability to align the minicells at a receiving station. More accurate minicell header information can be achieved by deriving a single header integrity check code (e.g., a cyclic redundancy code) for each ATM cell based upon minicell headers that have been inserted into contiguous locations in the ATM cell. By inserting the headers in contiguous locations, the receiving station can extract each header without having to rely upon the length indicator codes in each header, which may contain one or more bit errors. This, in turn, allows the receiving station to recompute the header integrity check code with far fewer errors, thus substantially increasing the probability of detecting and correcting the aforementioned errors and, ultimately, the ability to align the minicells.

Abstract: A telecommunication system has a sending entity, a receiving entity, and an ATM link between the sending and receiving entities for transferring ATM cells on specific separate ATM connections. The ATM cells include user ATM cells having a header and payload containing data in the form of a determined number of data units which carry data in microcells. The header includes an ATM connection pointer. The microcells have payload for carrying a variable size user data package and a microcell header containing code identifying a microcell connection. A microcell unable to fit in its entirety in a remaining space of an ATM cell belonging to a certain ATM connection is divided into a first part located in a least on following ATM cell belonging to the same ATM connection. Microcell size information is associated with each microcell. Methods for finding microcell boundaries are provided.

Abstract: In a telecommunication system that generates more than one type of communication data stream, in which each data stream exhibits a distinctive data transfer format, bandwidth utilization is improved by first reformatting the different data transfer formats so that all of the data is compatible with a common data transfer protocol, for example, the Asynchronous Transfer Mode (ATM) protocol. The communication data and the corresponding control data, required to maintain communication data alignment, are multiplexed into a single data stream which is then transmitted over a common telecommunication channel to a receiving station.

Abstract: In a telecommunication system that uses asynchronous transfer mode (ATM) with the ATM adaption layer (AALm) protocol as a data transfer infrastructure, a method and apparatus for segmenting and reassembling user data packets. The method and apparatus improve the quality and effectiveness of telecommunication data transfer by avoiding the problems associated with excessively long minicells.

Abstract: When using asynchronous transfer mode (ATM) in low bit rate applications, such as cellular voice communication, bandwidth utilization is significantly improved by employing decoupling minicells. Decoupling minicells are of predetermined length, such as one octet, and are inserted into the payload of ATM cells when there is a delay in the availability of assigned minicells. As soon as an assigned minicell, which contains actual user data, becomes available, the assigned minicell can be inserted into the payload of the current ATM cell immediately after the last decoupling minicell. Unlike prior methods, there is no need to wait until the next ATM cell to insert an assigned minicell.

Abstract: A method for switching synchronous transfer mode cells in a circuit emulated ATM switch using a layered protocol model. Each cell is delivered to the circuit emulated ATM switch on a frame oriented basis and each such cell comprises a header and a payload. The header comprises fields storing details about the cell. The payload comprises time slots carrying user data. The ATM switch is provided with means for assigning a predetermined number of time slots to a cell that is transported on a physical medium. The cell, referred to as a PR-PDU-cell, can have any of a number of sizes ranging from 4, 8, 12, 16, 20, 56 and 60 octets. This reduces the packetizing time of a cell.

Abstract: The process of detecting lost data cells in a telecommunication system that employs Asynchronous Transfer Mode is significantly improved in terms of bandwidth utilization by using an optional minicell or ATM cell sequence count. This may be accomplished by inserting the minicell or ATM cell sequence count into the ATM cell stream at intervals that can be adjusted at the transmitting station.