Abstract: A method and system for logical multicasting on an Asynchronous Transfer Mode (“ATM”) switch. There is a logical replication of cells on the same physical port of the ATM switch. A block of consecutive CIs is used by the controller in the switch to create new cells. The CIs are used to control the flow through the switch and for updating the VPI and VCI.

Abstract: Systems and methods for storing, or caching, VC descriptors on a single-chip network processor to enhance system performance. The single-chip network processor includes an on-chip cache memory that stores VC descriptors for fast retrieval. When a VC descriptor is to be retrieved, a processing engine sends a VC descriptor identifier to a content-addressable memory (CAM), which stores VC descriptor identifiers in association with addresses in the cache where associated VC descriptors are stored. If the desired VC descriptor is stored in the cache, the CAM returns the associated address to the processing engine and the processing engine retrieves the VC descriptor from the cache memory. If the VC descriptor is not stored in the cache, the CAM returns a miss signal to the processing engine, and the processing engine retrieves the VC descriptor from an off-chip memory.

Abstract: A method of transferring relatively short messages in an Asynchronous Transfer Mode network utilizing an emulated connectionless oriented technique. The method permits a short burst of data to be transmitted between users, utilizing a modified signaling scheme. The signaling scheme is modified so as to emulate a connectionless scheme whereby messages are transferred with no guarantee of delivery. The length of a message can be up to 47 bytes, i.e., the length of the data content of a single ATM cell. The method includes sending a setup message from the source user to the attached node requesting that a call of the fast type be set up. In response to this setup message, the attached node replies with a connect message indicating to the source user that it can immediately begin to transmit its short message.

Abstract: A router (105) includes multiple network interfaces (230-245) and a processor (220). Each of the network interfaces (230-245) receives port connection information associated with switches in a network (100). The processor (220) updates information pertaining to locations and paths to switches in the network (100) based on the received portion connection information. The processor further updates, based on the received port connection information, entries in a virtual circuit table such that the router provides virtual circuit paths to all switches in the network (100) within a radius of connection from the router (105).

Abstract: An asynchronous transfer mode (ATM) switching system includes a cell switching assembly having at least one switch port for transferring an ATM cell, and a subscriber board having a plurality of subscriber ports. A cell processing apparatus for use in the ATM switching system includes a look-up memory for storing control information for determining whether to copy an ATM cell from the switch port, and a cell copy controller for copying the ATM cell from the switch port and transferring ATM cells copied to the subscriber ports according to the control information stored in the look-up memory. If the ATM cell is a point-to-point communication cell, the ATM switching system translates the header included in the cell according to control information and transfers the ATM cell having the translated header to at least one of the subscriber ports.

Abstract: A switch system (20) switches at least sixty-four asynchronous transfer mode (ATM) input data streams (22) into at least sixty-four ATM output data streams (24). The switch system (20) includes a backplane assembly (38) having integral data transmission lines, integral clock transmission lines, and discrete slots (36). A single stage space switch circuit card (26), a clock circuit card (28), and input circuit cards (30) are connected to separate slots (36) in the backplane assembly (38). The integral data transmission lines are coupled between the input circuit cards (30) and the switch circuit card (26) and the integral clock transmission lines are coupled between the clock circuit card (28) and the input circuit cards (30). Data path lengths for the integral data transmission lines differ in the backplane assembly (38), and clock path lengths for the clock transmission lines differ in the backplane assembly.

Abstract: A communication device wherein path selection is performed taking account of the conditions of individual paths on a network. Storing means stores information relating to a plurality of paths, and selecting means selects the information relating to one of the paths stored in the storing means. Packet generating means generates a packet with a header matching the information relating to the path selected by the selecting means, and transmitting means transmits the packet generated by the packet generating means.

Abstract: The present invention comprises a smart subscriber line interface card (SLIC). The SLIC of the present invention includes a first and a second switch. A data receiver is coupled to a first output of the first switch to receive a user output signal and is adapted to generate a data receiver output therefrom. An ADC (analog to digital converter) is coupled to a second output of the first switch to receive the user output signal and is adapted to generate an ADC output therefrom. A data transmitter is coupled to a first input of the second switch and is adapted to generate a data transmitter output from a received digital network signal and couple the data transmitter output to the first input of the second switch. A DAC (digital to analog converter) is coupled to a second input of the second switch and is adapted to generate a DAC output from the received digital network signal and couple the DAC output to the second input of the second switch.

Abstract: An Asynchronous Transfer Mode (ATM)-based distributed virtual tandem switching system is provided in which a network of ATM-based devices is combined to create a distributed virtual tandem switch. The system includes an ATM switching network that dynamically sets up individual switched virtual connections. The system also includes a trunk interworking function (T-IWF) device and a centralized control and signaling interworking function (CS-IWF) device. The trunk interworking function device converts end office voice trunks from TDM channels to ATM cells by employing a structured circuit emulation service. The centralized control and signaling interworking function device performs call control functions and interfaces narrowband signaling and broadband signaling for call processing and control within the ATM switching network. Consequently, the ATM based distributed virtual tandem switching system replaces a standard tandem switch in the PSTN.

Abstract: In a path audit control method, (1) a unit (a discrete unit or common unit) within a switch holds bitmap information indicating whether each channel identifier is being used to establish a path; (2) a central controller sends the unit bitmap information indicating whether each channel identifier has been used to establish a path; (3) the unit compares bitmap information which it itself is holding with bitmap information that has been sent from the central controller; and (4) if the bitmap information held by the unit and the bitmap information that has been sent from the central controller do not match, the central controller and the unit cooperate to execute matching processing in such a manner that the compared items of bitmap information will be made to match.

Abstract: A network flow switch is provided for connecting a pool of IP routers to a cluster of IP servers sharing a single IP address without requiring translation of the IP address. Rather, all IP servers have the same IP address. The network flow switch routes packets to individual servers by writing the Data Link Layer address of the destination IP server in the destination Data Link Layer address field of the packet. However, no Data Link Layer address translation is required for packets transmitted from the IP servers to the IP routers. Since in a typical client-server environment, the number of packets sent from the server to the client is much greater than the number of packets sent from the client to the server, the Data Link Layer address translation requires very little overall processing time.

Abstract: A packet scheduling scheme capable of realizing a fair scheduling regardless of weights of connections. A packet scheduler has a plurality of packet queues for temporarily storing entered packets, to each of which a weight is set up; a packet input unit for entering packets into the packet queues; a scheduling information management unit for managing scheduling information for specifying an order to read out packets stored in the packet queues, according to a queue length of each packet queue and the weight set up for each packet queue; and a packet output unit for reading out and outputting desired packets from the packet queues according to the scheduling information.

Abstract: Methods and apparatus are described for translating identifiers that are used by computers to reference various entities such as data structures, external objects, or connections in a telecommunications network, from a bulkier less manageable format to a smaller more manageable format. Such translations are carried out to reduce the needless processing and memory demands that are made of a localized set of components when the large identifiers the set receives from other components include fields that none of the members of the set need to access. The invention is centerd around a two-stage look-up method wherein an inputted external identifier is divided into two parts. The first part of the inputted external identifier is used as an address into a first look-up table that contains base-addresses of a second look-up table. The second part of the inputted external identifier is used as an offset-address into the second look-up table.

Abstract: In an information processing system, a method to perform I/O (Input/Output) operations for an interpretative based program that is executing on an Interpretative Machine (IM). The method comprises the steps of: executing an interpretative based program on an Interpretative Machine (IM); receiving a request to pass data of unknown length out of the program; allocating a local buffer in the information processing unit to write the data of unknown length; writing the data of unknown length to the local buffer; determining the size of the data of unknown length in the local buffer; and passing the length of the data combined with the data in the buffer out of the program. In accordance with another aspect of the invention, a computer readable medium is described to carry out the above method.

Abstract: A base station apparatus for communicating with a specific base station and with a terminal that can move relative to the specific base station. The base station apparatus is provided to be able to move relative to the specific base station, and when the terminal has moved relative to the specific base station, the base station apparatus moves relative to the specific base station substantially in the same direction as the move direction of the terminal.

Abstract: A bin based method for determining a group size estimate for applications utilizing connectionless networks. The method places an indicator of group participants who match the key under a mask into bins, where each bin corresponding to the number of bits in the mask used to determine the match. When the number of bits in the mask is increased from m to m+1, all of the participant indicators in bin m are moved into bin m+1. When the number of bits in the mask decreases from m+1 to m, however, no participant indicators are moved. When a refresh packet is received from a particular participant whose indicator is in bin k, but the current mask is m bits, for k>m., the indicator for that particular participant is moved from bin k to bin m.

Abstract: An ATM switching system which includes PVC allocation circuits corresponding to output queues. At the time of arrival of the leading cell of each burst data, if the output line has room, the PVC of the burst data is stored as information for admission and identification. The subsequently-arriving cells having the same PVC identification information as the stored identification information are input to an output buffer, and the cells of the remaining burst data are all discarded. Even when a plurality of burst data compete for the same output line, the fact that all the cells other than the first-arriving admitted burst data are discarded prevents the cells from being input other than within a predetermined bandwidth and localizes the burst data affected by the cell discarding due to output queue overflow.

Abstract: A path merging type communication apparatus comprises a leaf interface unit, a root interface unit, a controlling unit, and a converting unit. The leaf interface unit and the root interface unit interface with air ATM communication unit or an ATM terminal unit. The controlling unit controls each structural unit of the apparatus. The converting unit merges input ATM cells and switches them. The converting unit adds input path identification information (such as a VPI and a VCI contained in an input ATM cell) and an intra-apparatus header (that contains a leaf IF unit number of the leaf interface unit to which the cell has been input) to the ATM cell and generates an output ATM cell.

Abstract: The present invention relates to a PID/section filter which is adapted without any restriction to an ATSC standard or a DVB standard, comprising a processor module for detecting a PID and a TID by decoding the input transport stream, downloading the information requested by the viewer, and controlling the operation of the each system unit in order to store the information on a memory or ignores it, a PID comparing circuit module for comparing the PID value stored on an internal register with the PID value from the processor module, a download circuit module for downloading the extracted information among the decoded information by the processor module, and an external memory managing module for storing the information extracted in-accordance with the request of the viewer among the information decoded on the processor module.

Abstract: Methods and apparatus are provided for designing IP networks with substantially improved performance as compared to existing IP networks such as, for example, those networks designed under best-effort criteria. Particularly, the invention includes methods and apparatus for: computing worst-case and optimistic link capacity requirements; optimizing network topology; and determining router placement within a network.

Abstract: A system (10) is provided for identifying a processing port (12) and a link (22) at which a cell (24) is received. The system (10) includes a logical link table (14) having a plurality of logical link entries (30). Each logical link entry (30), which corresponds to a particular link (22) of a processing port (12) associated with the logical link table (14), specifies a numerical value. The processing port (12) may receive the cell (24) at one of a plurality of links (22). The processing port (12) can convert the cell (24) by replacing a numerical value of an identification field, such as a virtual channel identification field (28), of the cell (24) with the numerical value specified by the logical link entry (30) corresponding to the link (22) at which the cell (24) is received. A switch control module (18), which is connected to the processing port (12), may receive the converted cell (38).

Abstract: A method is disclosed for transmitting data packets in wide area networks (WAN) by way of a synchronous digital data transmission network (SDH), wherein the data packets are packed into synchronous transport modules (STM-N) and are transmitted by way of virtual connections formed by subunits of synchronous transport modules of the same size. The virtual connections are entered into an address table and an evaluation of the target address of the data packets takes place in one of the network elements of the synchronous digital data transmission network. On the basis of the address table and the target address, at least for a part of the data packets, a decision is made by at least one of the network elements of the synchronous digital data transmission network as to which one of the virtual connections is used to transmit this data packet. Furthermore, a network element is disclosed, which operates in accordance with the transmission method.

Abstract: The present invention relates to a frame relay interworking service control method using a permanent virtual connection, whereby a frame relay subscriber's service information is registered to ATM exchange system, ATM exchange system inner path to the frame relay connection due to registering the frame relay connection to the registered subscriber is connected by means of PVC the registered frame relay. Such this invention is that the existing frame relay subscriber/network can be interworked with ATM exchange system without an extra device or function since ATM exchange system accommodates the frame relay interface.

Abstract: An automatic VLAN configuration information setting system comprising an automatic VLAN configuration information setting device and one or more switching hubs, for setting VLAN configuration information of the switching hubs, is proposed. When a terminal is added to or removed from an Ethernet port of a switching hub by the user, a VLAN alteration request section of the switching hub detects the event, and a VLAN alteration request is transmitted to the automatic VLAN configuration information setting device. In a database of the automatic VLAN configuration information setting device, VLAN detailed information concerning all the VLANs managed by the automatic VLAN configuration information setting device is stored. A VLAN configuration instruction text editing section of the automatic VLAN configuration information setting device edits a VLAN configuration instruction text (an instruction scenario) by referring to the VLAN alteration request and the VLAN detailed information.

Abstract: An Ethernet Local Area Network uses a star topology connecting user stations to a Communications Switching Module (CSM) with 10Base-T or 100 Base-TX UTP cable. Each user station typically has a digital telephone and a data communication device, such as a PC communicating with the CSM through a common UTE adapter. Delay-sensitive digital voice signals and non-delay sensitive user data are transported in master Ethernet packets of fixed length transmitted at a fixed rate. Segmentation and re-assembly of data is performed in the UTE adapters and in the CSM.

Abstract: VPI/VCI of an ATM cell is translated into an internal ID by distributing VPI/VCI entries into sections in a table according to a portion of each VPI/VCI entry. A section to be searched according to the portion of a VPI/VCI of the received ATM cell is selected; and a search over the selected section is performed to find an entry corresponding to the VPI/VCI of the received ATM cell. An internal ID corresponding to the found entry is outputted.

Abstract: A method whereby local area network (LAN) multicast traffic flows are defined and set up by the network management system (NMS). Network efficiency is maximized and performance degradation of the network and workstations connected thereto is reduced. The method utilizes standard 802.1D bridging infrastructure built into conventional level 2 network switching devices to permit a administrator to define a multicast flow, otherwise known as a virtual LAN (VLAN) or a ‘Session VLAN,’ as a multicast application that can be mapped to a multicast MAC address. The multicast MAC address is then utilized in the transmission of the multicast messages. The NMS declares a session VLAN across all the level 2 devices in the network utilizing standard SNMP and members of the session VLAN can be added and removed. Each device then translates the SNMP requests to an operation on its standard 802.1D static addresses.

Abstract: A user network interface device for interfacing between synchronous optical network (SONET)/synchronous digital hierarchy (SDH) which is characterized by a continuous stream of frames of data and an asynchronous transfer mode (ATM) characterized by a non-continuous stream of cells of data. The user network interface device includes an integral phase lock loop circuit to recover clock and data from an encoded incoming stream of data. In another embodiment, the network interface device synthesizes a high speed transmit clock from a low frequency reference source.

Abstract: An ATM network includes a set of interconnected switches and gateways. The ATM network is capable of providing both a conventional connection-oriented service or a connectionless service. Where a connectionless service is required, at the input interface, source and destination addresses are inserted into the header and fields in the header are set to values which indicate that a connectionless service is required and whether or not additional processing is also required. At each node between the input interface and the output interface, where a connectionless service is required, each ATM cell is routed in accordance with its source address and destination address and/or a routing table which is set up by routing protocol or network management.

Abstract: A network includes a number of domains ("layer 2 domains") interconnected by routers. Within each domain, traffic is forwarded based on MAC addresses (or other data link layer addresses). The routers route traffic based on IP addresses or other network layer addresses. To restrict network connectivity, a network administrator specifies connectivity groups each of which is a group of sub-networks that are allowed to communicate. The administrator also specifies which entities (MAC addresses, ports, or user names) belong to the same group. The entities may be in the same or different domains. A computer system automatically creates access control lists for routers to allow or deny traffic as specified by the administrator. The computer system also creates VLANs to allow or deny traffic as specified, wherein each VLAN is part of a domain or is a whole domain. Connectivity within each domain is restricted by VLANs and connectivity between domains is restricted by access control lists.

Abstract: An apparatus and a method for shaping ATM cell traffic emitted onto a virtual path connection in an ATM network are described. Component virtual channel connections are arbitrated at an aggregation point utilizing a hierarchical, multi-level arbitration technique. The technique provides both virtual path shaping and controllability of underlying virtual channel connections with an improved fairness performance amongst all the aggregating virtual channel connections.

Abstract: An asynchronous transfer mode (ATM) based very-high-bit-rate digital subscriber line (VDSL) system for connecting a subscriber between different data service providers includes an ATM network connected to data service providers. A host digital terminal (HDT) is connected to the ATM network by an ATM permanent virtual circuit (PVC). Each of the ATM PVCs is associated with a corresponding one of the data service providers. The ATM PVCs connect the HDT to the data service providers. The HDT and the data service providers communicate data signals on the ATM PVCs through the ATM network. A customer provided equipment (CPE) data device is connected to the HDT by a VDSL PVC. The CPE device and the HDT communicate data signals on the VDSL PVC. A subscriber personal computer is connected to the CPE device for communicating data signals with the CPE device. The personal computer is operable to generate a channel signal corresponding to a selected one of the data service providers.

Abstract: A system for forming one point-to-multipoint connection provides various service attributes in an ATM network in response to differences in service attributes requested by receiving parties or differences in available resources. A network node sets up an output VC (Virtual Channel) link to be connected to an input VC link, the VC links being parts of a point-multipoint connection, receives a new VC link set-up request, and adds to the point-multipoint connection, in response to the new VC link set-up request, new output VC link with service attribute different from that of the input VC link.

Abstract: An ATM network switch (11) including a buffer (24) for buffering the flow of ATM cells and a congestion control mechanism (23). The congestion control mechanism establishes a value Max, representing the maximum permissible number of ATM cells which may be stored in the buffer. The switch includes a predetermined offset value K for determining the maximum occupancy of the buffer for the connection. The congestion control mechanism determines the total number of cells TSC currently stored in the buffer and the number of cells VcCnt stored for a given connection, determines the remaining capacity BS of the buffer, calculates an adjusted value of Max as a function of TSC and BS, compares the adjusted value Max' with VcCnt, and discards the cell if VcCnt is greater than the adjusted value.

Abstract: An exchange apparatus for exchanging packets based on a predetermined exchange system, including a plurality of input ports into which the packets are input, an input port identifier adding circuit for adding to a header region of each of the packets an input port identifier indicating the input port from which the packet was input, an output port identifier adding circuit for routing each of the packets to an output port and adding an output port identifier indicating the routed output port to each of the packets based on address information included in the header region and the input port identifier, and a packet exchanging circuit for exchanging the packets and outputting the same from the routed output port based on the added output port identifier.

Abstract: A path defining/changing/deleting section sets in advance the definition of the setup of a PVC connection in a PVC connection object management table as a PVC connection object. Each PVC connection object has an attribute indicating an active or inactive state. When a request is made by a reservation controlling section for activating or deactivating an object PVC connection, a PVC active/inactive state controlling section can immediately read from the PVC connection object management table a PVC connection object indicating the definition of the setup of the object PVC connection, to send commands based on the definition to each of network elements (NE) which comprise an information communications network.

Abstract: An on-demand system controlling on-demand services between a media server and subscriber terminals, the system includes an ATM-HUB unit which performs a path setting operation in accordance with a PVC (Permanent Virtual Connection) function, and a path setting management server. The ATM-HUB unit has previously set paths between the subscriber terminals and the path setting management server and between a controller of the ATM-HUB unit and the path setting management server in accordance with the PVC function at a time of setting environments of the system. A subscriber terminal supplying a media transmission request to the path setting management server via the path set between the subscriber terminal and the path setting management server.

Abstract: The present invention is directed to a system and method of sending packets between ports on trunked network switches. The method includes providing a first switch having a plurality of communication ports thereupon, and providing a second switch having a plurality of communication ports thereupon. A trunk connection is provided between the first switch and the second switch, with the trunk connection including at least two of the plurality of ports from the first switch being connected to at least two of the plurality of ports of the second switch. A rules table is provided, defining a set of rules identifying which port of the trunk connection will be used for communication. A packet is sent from a first port on the first switch to a second port on the second switch. The packet is received at an ingress submodule of the first switch, and a lookup is performed on one of a source address and a destination address of the packet based upon a lookup table provided in the ingress submodule.

Abstract: A network architecture and service platform for providing virtual private network services ("VPN") over an ATM network. The architecture provides services for voice, video, and data traffic among multiple VPN customers over a shared ATM network by implementing intelligent control devices to perform enhanced processing of ATM call setup messages, including validations and routing translations. Hierarchical routing mechanisms provided by ATM, along with customized customer addressing schemes, are used to overlay customer VPNs as higher-level networks onto the shared ATM network. The control devices translate customer ATM VPN address to internal ATM network addresses. The ATM switch network then performs lower-level network processing, using internal network addressing, to setup a virtual connection for a VPN call. The intelligent control devices may also explicitly state the end-to-end route.

Abstract: A set of logical networks is established on top of a physical network Next, a predefined objective function, closely related to the operation and performance of the physical network, which physical network is viewed as the set of logical networks, is optimized with respect to at least one set of decision variables. Finally, the decision variables in accordance with the optimization are used to control the operation of the overall network system. Physical transmission resources are partitioned among logical networks. Traffic loads are distributed among routes interconnecting the nodes of node pairs.

Abstract: A design for a network route server in which network routing functions are distributed throughout the processing elements that constitute a switching node, while maintaining the global identity and routing information exchange functions of a route server element (RSE). Intelligent line-cards are provided having the ability to route independently of the RSE. This removes the RSE as a bottleneck resource and ensures that the capacity of the switching node is limited only by the switching capacity of its switch fabric. The RSE serves the functions of network topology discovery and routing table construction using a network topology database and an optimal routing algorithm. Copies of the dynamically maintained routing tables are distributed to the intelligent line-cards on a periodic basis governed by predetermined criteria. Wider geographical distribution of the RSE is enabled and most efficient utilization of the switch fabric is ensured. Scaling of distributed switching architectures is also enabled.

Abstract: Methods for load balancing a network are disclosed. Resource rebalancing includes remapping of pathways between nodes, e.g. servers, and resources, e.g. volumes/file systems. Resource rebalancing allows the network to reconfigure itself as components come on-line/off-line, as components fail, and as components fail back. In an embodiment of the invention a method for load balancing on a network is disclosed. The network includes server nodes and resources. Each of the resources are coupled to at least two of the server nodes. The method for load balancing comprises the acts of detecting a change in an availability of the server nodes; defining a first set of available server nodes and a second set of available resources and selecting for each one of the members of the second set a corresponding member of the first set to server as the administrative server for handling an administrative portion of an I/O request for the corresponding resource of the second set.

Abstract: An ATM transmitter distributes an ATM transmission process function to plural electronic circuit packages and performs transmission process by forming routes between the plural circuit packages. The routes can be flexibly varied while a configuration of a variety of process functions are managed. The cell distribution section which has plural input and output terminals connected to respective electronic circuit packages forms a route among respective ones of the arbitrary input and output terminals so that receive ATM cells are input and output between respective electronic circuit packages. Process functions are arranged for each electronic circuit package. The function configuration of all the electronic circuit packages is previously set. Thus, a route formation is indicated to the cell distribution section. In other case, input and output terminals for each route are sequentially arranged along the route. The control order of receive ATM cells is previously set.

Abstract: A method and apparatus for layer 3 switching packets between locally attached virtual local area networks without using a routing protocol are provided. A learning internetwork switch is connected between a router and a plurality of virtual local area networks. Communications between devices on the virtual local area networks and the router pass through the learning internetwork switch. By inspecting certain packets that flow between the devices and the router, the learning internetwork switch learns the location of the devices without having to use a routing protocol. The learning internetwork switch learns the network layer and the data link layer addresses of the various devices. Once the learning internetwork switch has learned the location, the network layer address and data link layer address of a device, the learning internetwork switch can forward packets between devices on different virtual local area networks using layer 3 switching without involving the router.

Abstract: A fault tolerant multicast ATM switch fabric is constructed as a multistage interconnection network through which cells move from input to output along a pre-established data path. The control phase proceeds concurrently with the data phase by which cells move continuously without idle clock cycles in between. The control logic resolves the state of the switching elements and sends this state information to the data path logic ahead of the cell transfer. The switch consists of three IC designs: control, data path, and switch port controller ICs. The successful realization of the switch relies critically on the design of the control IC which incorporates a new combinatorial hardware design running a dedicated algorithm. A switch port controller delegates, based on local decisions, the replication and routing of multicast cells to a selected group of switch port controllers on a per call basis, thereby supporting any multicast group in a unified manner.

Abstract: An available bit rate scheduler for asynchronous transfer mode communication of a plurality of cells over a communication network in which each cell is characterized by a virtual circuit communication channel and in which each virtual circuit is characterized by one or more profiles. Each profile has a group of sub-profiles, with each sub-profile having a unique bandwidth allocation component. The scheduler incorporates a profile queue buffer for receiving, pairing and storing the profiles and sub-profiles and, a link list processor coupled to the profile queue buffer to receive the profile, sub-profile pairs. The link list processor detects null profile, sub-profile pairs in the buffer and, over-write them with a selected one of the virtual circuit profile, sub-profile pairs. A valid pending register of length p bits, and a memory are coupled to the link list processor.

Abstract: A switch for use in an ATM network is disclosed. The switch is designed to perform a function beyond that normally achievable with a virtual path switch functioning in accordance with the ATM standard. The switch according to the invention has data stored in a look-up table (431-433) which allows it to identify communication cells of particular individual virtual channels, indicated by the virtual path identifier (VCI), although these cells cannot be distinguished on the basis of their virtual path indicators (VPIs). This identification is attempted before the usual step of forwarding an incoming communication cell based solely on its virtual path indicator. A priority circuitry (44) ensures that entries associated with the combined VPI/VCI is given a priority over those associated only with the VPI. The switch can extract cells of individual virtual channels passing through it. It can also insert virtual channels into the ATM network.

Abstract: A virtual connection created between an application program and a selected I/O device is used as a communications medium for controlling I/O processing of the I/O device by the application program. The virtual connection is implemented as a system area network connecting a process of the application program and the I/O device. The application program registers the application program's memory that the application program shares with the I/O device (i.e., gives access rights to the I/O device) with the system area network. Once the virtual connection is created and initialized, the application program uses the virtual connection to send request messages for I/O services to the I/O device and to receive reply messages from the I/O device. The I/O device uses the virtual connection to obtain source data from the application program's memory for I/O write operations and to transfer data to the application program's memory for I/O read operations.

Abstract: The method of the present invention achieves a desired assignment of the physical cell slots comprising a time division multiplexed frame to embedded channels by ascribing an element address to uniquely identify each of the cell slots of the frame. A logical assignment of the cell slots of the frame is made to the embedded channels to be established between one or more specific data sources and sinks. A transform chosen to produce a particular distribution of assignments is then applied to the set of element addresses to produce a set of cell slot addresses, each of which uniquely identifies each cell slot of the frame by its relative physical position within the frame. Each of the element addresses (used to logically associate a cell slot with a channel to be established) is uniquely linked on a one-to-one basis with one of the set of cell slot addresses (used to identify relative position of a cell slot within the frame) through the predetermined transform.

Abstract: A supervision control system for an ATM cell switching system counts the number of cells transmitted from a subscriber in a predetermined duration unit, attaches a sign to the cells when the counted value exceeds a predetermined value, and discards the cells to which the sign is attached when a buffer does not have enough capacity during a cell multiplexation.