Abstract: VC multicast implementation scheme utilizing VP tunneling over public ATM VP switched networks utilizing P2P and P2M connections to provide VC multicast capability to the attached private ATM networks. The border ATM VC switch in each private ATM network is connected to the ATM VP switch in the public ATM network via a physical interface adapted to carry one or more P2P VP tunnels. A P2P VP tunnel is established from each VC switch to all other VC switches connected to the public ATM network. A dedicated P2M VP tunnel is established between the source VC switch to each of the destination VC switches connected to the public ATM network. For each multicast connection to be established, a VPI/VCI value pair is allocated over the dedicated P2M VP tunnel used to transmit data associated with all P2M calls for all the P2P VP tunnels carried by the physical interface.

Abstract: An apparatus for and method of encapsulating Ethernet frame data in HDLC frames for transmission over a VDSL transport facility. The HDLC frames are transmitted over a point to point VDSL link where they are subsequently extracted and forwarded as standard Ethernet frames. The VDSL facility transport system comprises one or more Ethernet to VDSL CPEs coupled to a DSLAM over a VDSL transport facility. The Ethernet to VDSL CPE functions to receive a 10BaseT Ethernet signal and encapsulate the Ethernet frame into a HDLC frame for transmission over the VDSL facility. In one embodiment, a single chip microcontroller on the CPE performs both Ethernet controller and HDLC controller functions. The DSLAM is adapted to receive HDLC frames from one or more CPEs, extract Ethernet frames therefrom and generate and output a standard Ethernet signal. Ethernet frames are encapsulated within HDLC frames and transmitted on the wire pair without regard to the state of the SOC signals.

Abstract: A method for detecting leaks in an ATM network, the method including the steps of a) creating an entity interconnection map including mappings of port interconnections among a plurality of network nodes, the plurality of network nodes includes a plurality of network endpoints and at least one network switch, b) creating an endpoint map including at least one endpoint mapping of at least one port to at least one virtual identifier for at least one of the network endpoints and a leak indicator for the at least one network endpoint indicating that the network endpoint is either of a transmitting endpoint and a receiving endpoint, c) creating a switch map including at least one switch mapping of at least one port and virtual identifier grouping to at least one other port and virtual identifier grouping for the at least one network switch, d) initializing a leak indicator for each of the endpoint mappings and the switch mappings to indicate a leak condition, e) traversing a virtual channel connection from each tra

Abstract: An apparatus for and a method of establishing a connection between a source and destination node using multiple parallel paths. To establish a connection, bandwidth capacity on one or more parallel paths are aggregated and combined to form a route having a bandwidth larger than any single path. A technique similar to inverse multiplexing is used at the source end to split the cell stream into multiple parallel paths. At the destination end, the parallel multiple cell streams are inverse demultiplexed and the multiple cell streams combined into a single cell stream. The parallel routes are established by building parallel VCCs for the same call via the network. The ATM signaling process at the source and destination nodes is modified to accommodate multiple VCCs. In addition, the hardware at each source and destination node is configured to perform the inverse and inverse demultiplexing.

Abstract: A crossbar switching system utilizing broadcast buffering and broadcast buffer management to improve the transmission of variable length broadcast packets through the switch. Transmission of unicast traffic is halted and a plurality of broadcast packets are transmitted consecutively. Once the broadcast packets have finished transmission, unicast packet transmission resumes. Improved performance is achieved by consecutively transmitting many broadcast packets at a time, thus reducing the lengthy time waiting overhead typically associated with stopping unicast transmission and transmitting a single broadcast packet. A broadcast buffer or queue is placed on each interface card for storing broadcast packets during unicast transmission.

Abstract: An apparatus for and a method of implementing multicast registration in an ATM based ELAN. The present invention provides a mechanism for a LEC to register to receive all multicast group traffic flows without requiring the LEC to generate a separate request for each multicast MAC address. The mechanism of the present invention provides means for a LEC to register to receive all multicast flows by defining an ‘all_multicast’ TLV and including this TLV in the LE_REGISTER_REQUEST request message sent by the LEC. The LEC, LES and SMS are modified to perform the multicast registration/unregistration method of the present invention. The LEC generates the LE_REGISTER_REQUEST message and includes the all_multicast TLV indicating that the LEC desires to receive all multicast traffic flows in the ELAN. The LES, upon receipt of such an all_multicast TLV, adds the LEC to its list of LECs to receive all multicast traffic and communicates the related information to the SMS.

Abstract: A novel BUS entity utilizing the forwarding engine in a conventional LAN switch incorporating an ATM interface. The forwarding engine is adapted to assemble Ethernet frames from ATM cells and to segment Ethernet frames back to ATM cells. The switching fabric in a conventional LAN switch is adapted to perform the segmentation and re-assembly (SAR) function of the BUS whereby ATM cells are assembled into Ethernet frames, switched and segmented back to ATM cells. In operation, one or more Multicast Send VCCs transmit traffic destined for the BUS to the modified LAN switch of the present invention. The switching fabric is configured to switch the received traffic to an appropriate outbound Etheret port. The outbound Ethernet port is looped backed to itself and input to the switching fabric. Switching fabric is configured to output the traffic to the appropriate Multicast Forward VCC for distribution to the LECs.

Abstract: A system for appending data to a packet whereby the original CRC calculated by the transmitting station is not modified and is retained in order to determine the occurrence of transmission errors at the receiver. The invention is applicable in communication systems whereby the data to be appended to the packet comprises a fixed length. The invention appends the data in the form of a tag to the tail of the packet after the original CRC and, in addition, determines and appends a tag CRC to the tail of the packet following the tag data. The tag CRC has a value such that the CRC machine in the receiver generates a constant CRC value even though the packet length was increased. A tag CRC is generated that when appended to the packet produces the same result as if the packet was processed through the CRC machine without any data appended.

Abstract: A method for optimizing the detection of a change in MIB information, the method including the steps of creating a MIB information request, sending the request to a SNMP agent, receiving a first response to the request from the SNMP agent, wherein the first response includes MIB information encoded as a byte array, and comparing the first response byte array to a comparison byte array to determine a difference therebetween.

Abstract: A method for automatically connecting a DHCP endpoint to a VLAN in an ATM network having a switch operative to provide LAN emulation for a plurality of non-ATM endpoints, the method including the steps of maintaining a LEC for the VLAN in the absence of any request by any of the endpoints to communicate via the VLAN, the LEC having been previously established for the VLAN, connecting the DHCP endpoint to a port on the switch, determining a predefined association between the VLAN and either the address of the port or the network address of the DHCP endpoint, and mapping either the network address of the DHCP endpoint or the address of the port to the LEC for communication via the VLAN.

Abstract: A bidirectional direct sequence spread spectrum half-duplex RF modem which can be applied to transmit and receive numerous types of analog and digital pulse modulation. The modem incorporates two different SAW devices fabricated on a single monolithic substrate. A first SAW device is used as a resonator in the oscillator circuit while a second SAW device is used as the correlator for transmit and receive operations. The RF modem operates as an analog or digital pulse transmitter and receiver and is adapted to be generic and versatile enough to be used in many different types of data communication systems, such as OOK, PWM and PPM. The RF modem can be used as the physical (PHY) layer in a layered communication system such as the ISO OSI communication stack. In an alternative embodiment, the transmission bit rate is increased using a plurality of correlators wherein each is configured with a unique function (i.e., code) that is orthogonal with all other functions.

Abstract: An apparatus for and method of enabling the debugging and testing of complex multilevel PNNI based ATM networks. The invention has applications in networks wherein one or more nodes implement only the Minimum Function PNNI implementation and wherein these modes must operate correctly in a PNNI hierarchy environment. A plurality of PTSEs representing simulated virtual portions of an ATM network are injected into a node under test. The PTSEs represent hierarchical portions of ATM networks that are difficult or impossible to implement. The virtual portions of the networks may or may not have been able to be created using real physical network elements. The method includes first generating the injection file containing all the PTSEs to be simulated and then injecting this file into the node under test.

Abstract: An apparatus for and method of reducing the soft output information packet to be computed by a soft symbol generator. The reduced soft output information packet generated by the soft symbol generator is subsequently used by a soft symbol to soft bit mapper which functions to convert soft symbol decision information into soft bit decision information. A symbol competitor table is constructed that includes the most likely symbol competitors for each bit of the symbol. The table is populated with m entries for each possible symbol value, where m represents the number of bits per symbol. Symbol competitors am retrieved from the table in accordance with hard decisions. Soft symbol information is generated only for symbol competitors rather than for all possible symbols thus substantially reducing the size of the information packet.

Abstract: A system comprising a single sender SMS for forwarding multicast traffic is collocated in the same device as the LEC thus creating an optimal distribution path for multicast traffic. This reduces the latency of transmission of multicast traffic from sender to receivers by eliminating the need to transmit cells from the LEC to the SMS via the network and reassemble cells into frames and segment frames into cells. The SMS functions as a private SMS for exclusive use by the LEC alone. The SMS of the present invention enables a LEC to distribute multicast traffic in a very efficient manner. The LEC communicates with the SMS directly via the operating system internal messaging subsystem or equivalent. The multicast traffic is sent on a P2M connection from the sending LEC via the SMS to all the receiving LECs interested in listening to a given MMAC. In a first embodiment, the LEC internally has knowledge of the existence of the private SMS and is inhibited from issuing a LE_ARP_REQ to find the SMS.

Abstract: A method for adjusting an ATM switch local service policy based on a non-ATM protocol service parameter, the method including the steps of inspecting the payload of an ATM PDU received at a switch along at least one VCC to identify a non-ATM PDU protocol identifier included in the payload, inspecting the payload to identify a non-ATM PDU service identifier associated with the non-ATM PDU protocol identifier, and selectively adjusting a local service policy attribute within the switch for the at least one VCC based on the non-ATM PDU service identifier in accordance with an adjustment value previously associated with the non-ATM PDU protocol identifier and the non-ATM PDU service identifier.

Abstract: A novel crossbar switching matrix that improves the transmission of variable length broadcast packets by greatly reducing transmission latency time. Unicast traffic is halted in the middle of packet transmission operations and the broadcast packet is transmitted. Once the broadcast packet has finished transmission, unicast packet transmission resumes without any loss of data. A unicast buffer is used to store the unicast packet while the broadcast packet is being transmitted. A broadcast buffer is used to buffer the broadcast packet as it egresses from the switch matrix. In this fashion, the broadcast information is given high priority and passes quickly through the switch without the large delays associated with the prior art switch matrixes. The crossbar switch matrix of the present invention is applicable to any switching matrix adapted to switch variable length data units.

Abstract: A system for establishing static SVCs (i.e. permanent SVCs) whereby the results of the signaling/routing protocol generated when the network is first brought up are stored in a ‘permanent SVC’ memory. The results of the signaling/protocol that were previously stored are restored from memory in the event the connections must be re-established again. The connections are restored from memory without the need to execute the signaling/routing algorithms and protocols again. Use of the signaling/routing protocols yields the same connections that were already stored previously in the memory from when the connections were originally established. The system of the present invention is applicable to any connection-oriented network that utilizes signaling to establish connections between network users. The signaling and routing algorithms and protocols would not need to be run for every connection request.

Abstract: A method of determining the optimum route from a source to a destination node in an ATM network utilizing fuzzy logic processing to determine the optimum route based on a set metrics that may or may not be related to each other. The invention utilizes well known fuzzy logic techniques to perform optimization and calculations based on intuitive rules rather then complex mathematical solutions. The method of the invention can be applied to routing algorithms to determine the optimum route when it is desired to optimize the route based on a large number of metrics, attributes and/or parameters. The fuzzy logic processing is divided into two phases each having its own set of rules that the input data is applied against. Fuzzy logic processing is performed for all candidate routes wherein the route chosen is the one having a maximum link quality.

Abstract: A system for reducing the memory requirements of an ATM device utilizing one or more temporary code uploads to bring needed portions of application code into the memory of the ATM embedded system on a temporary basis. The present invention functions to divide the code necessary for operation of the ATM device into two categories: (1) application code that is seldom used or code used only once and (2) all other application code. The application code that is seldom used or used only once is removed from the memory of the ATM embedded system and placed in a software storage device external to the system. This serves to significantly reduce the memory requirements of the ATM device, by as much as 40% in come cases depending on the size of the application code portions.

Abstract: A system of building a hierarchy in a PNNI based ATM network utilizing one or more proxy SVCC-based RCC entities. The invention separates the routing, signaling, etc. functions from the functions required to be performed by the peer group leader and the logical group node. A dedicated computing platform is connected to the network but does not perform functions related to routing, signaling, etc. Rather, it is dedicated to running peer group leader and logical group node functions, including complex node representation (summarization calculations) of the child peer group. The dedicated computer has PVCs connecting it to one or more entities that are termed ‘proxy SRCC’ nodes. The proxy SRCC nodes perform the SRCC functionality on behalf of the dedicated computer. When the border nodes in the peer group run the Hello FSM over outside links they each advertise the closest proxy SRCC entity, which is themselves.