International Business Machines Corporation

Cisco Technology, Inc.

Ibm France

Gilles Toubol

Patrick Michel

Alain Benayoun

Fabrice Jean Verplanken

Daniel Orsatti

Jean-Francois Le Pennec

Jean L Calvignac

Claude Basso

Jean Louis Calvignac

Claude Pin

Jean-Luc Frenoy

Pierre J Huon

Gerard Barucchi

Eric Lallemand

Andre G Tracol

Luc Torres

R Glaise

Jose Galcera

Eric Saint Georges

Francois Nicolas

The disclosed invention relates to a re-synchronization system that operates in a switching arrangement receiving a plurality of incoming data packets. The switching arrangement is made of an active switch card that transmits the incoming data packets and a backup switch card that may be re-activated by an operator after replacement. The re-synchronization system is implemented in each switch card. When the backup switch card is re-activated, both switch cards receive the incoming data packets and the system of the invention allows to re-synchronized both switch cards by controlling the transmission of the incoming data packets out of each switch card until the same data packets are transmitted. The re-synchronization system further comprise storage for storing the incoming data packets and detector for detecting a re-synchronization information among the incoming data packets.

System and method for packet switch cards re-synchronization

A data packet switching node that temporarily stores data packets received from at least one source network adapter and transmits them to at least one destination network adapter comprises a data packet flow control system to control the data packet flow. The data packet flow control system comprises identifier to determine the at least one destination adapter of each received data packet. Then, flow control logic coupled to the storage allow computing a data packet flow value representing the traffic for the at least one destination adapter. The data packet flow value is transmitted simultaneously to the at least one source network adapter and to the at least one destination network adapter each time a data packet for the at least one destination network adapter is stored into the storage.

Dynamic data packet flow control for packet switching node

A switchover system and method is described. The invention preferably operates in a data packet switching system for transmitting through a switching arrangement data packets that comprise at least a data packet identifier. The switching arrangement comprises at least an active switch card associated to a backup switch card. And the active switch card and the backup switch card receive simultaneously at least a data packet and transmit it to a network adapter device. The switchover system comprises active and backup means for respectively storing at an active and backup data packet address the transmitted at least data packet. It also comprises switchover detecting means coupled to the active and backup storing means for detecting a switchover event, and control means coupled to the active and backup storing means and to the switchover detecting means for setting the backup storing means when a switchover event is detected.

Switchover system and method in a data packet switching network

A data transmission system comprising a packet switch module interconnecting LAN adapters, a plurality of input and output ports connected to the LAN adapters such that each pair of input and output ports defines a crosspoint within the switch module, and a memory block located at each crosspoint of the switch module for storing at least one data packet. At each clock time, a scheduler causes a data packet stored in a memory block, among all memory blocks corresponding to a given output port, to be transferred to that output port. The system further comprises a configuration interface mechanism for sending configuration data to the memory control means of memory blocks located at pre-determined crosspoints such that a packet received by corresponding input ports from an input adapter having a speed n times faster than an input adapter transmitting to a single input port is transferred to corresponding output ports at a speed which is n times the transfer speed between a single input port and a single output port.

Data transmission system with multi-memory packet switch

Data transmission system comprising a plurality of Local Area Networks (LANs) (-to-) interconnected by a hub () including the same plurality of LAN adapters (-to-) respectively connected to the LANs and a packet switch () comprising at least a packet switch module interconnecting all LAN adapters wherein a packet transmitted by any adapter to the packet switch includes a header containing at least the address of the adapter to which the packet is forwarded. The system comprises a memory block at each crosspoint of the switch module including memory control means for determining from the header of the received data packet whether the packet is to be forwarded to the output port associated with the crosspoint and a data memory unit for storing at least the data packet into the data memory unit before sending it to the output port. The memory control means analyzes all the bytes following the header when it includes a specific configuration indicating that the packet is a multicast address packet preceding a multicast frame in order to determine whether the packets of the multicast frame are to be forwarded to the output port.

Expandable self-route multi-memory packet switch with a configurable multicast mechanism

Data transmission system comprising a plurality of Local Area Networks (LANs) (-to-) interconnected by a hub () including the same plurality of LAN adapters (-to-) respectively connected to the LANs and a packet switch () comprising at least a packet switch module interconnecting all LAN adapters wherein a packet transmitted by any adapter to the packet switch includes a header containing at least the address of the adapter to which the packet is forwarded. The system comprises a memory block located at each cross point of the switch module including a data memory unit for storing at least a data packet and memory control means for determining from the header of the received data packet whether the packet is to be forwarded to the output port associated with the cross point and for storing the packet into the data memory unit and a scheduler for causing at each clock time a data packet stored in a data memory unit of a memory block among all memory blocks corresponding to the output port to be forwarded to this output port.

Self-route expandable multi-memory packet switch

Data transmission system comprising a plurality of Local Area Networks (LANs) (-to-) interconnected by a hub () including the same plurality of LAN adapters (-to-) respectively connected to the LANs and a packet switch () interconnecting all LAN adapters wherein a packet transmitted by any adapter to the packet switch includes a header containing at least the address of the adapter to which the packet is forwarded. The system comprises a memory block located at each cross point of the switch module for storing any data packet which is received from the input port corresponding to the cross point and which is to be forwarded to the output port corresponding to this cross point, and a scheduler associated with each output port for selecting at each clock time a memory block among all memory blocks corresponding to the output port and causing the memory block to forward the stored data packet to the output port when predetermined criteria are met.

Self-route expandable multi-memory packet switch with distributed scheduling means

According to the invention, a device for transferring data between two workstations connected to a network is provided. This device comprises means for distributing data among a plurality of links of the network. Preferentially, the device comprises a dual-port memory for storing the data. In a preferred embodiment, the device further comprises a high speed interface for transmitting data from a workstation to the memory, associated with each link, a low speed interface for transmitting a part of the data from the memory to this link, and a controller for monitoring the data flow between the workstation and the plurality of links, by controlling the memory and the interfaces.

Device for connecting two workstations with several links

A data transmission system, which includes multiple local area networks (LANs) coupled by a hub via multiple LAN adapters and an ATM crossbar switch coupling all LAN adapters. At least a requesting LAN transmits LAN data frames to at least a destination LAN. The LAN data frames are converted into concatenated slots of the same size and transmitted through the ATM crossbar switch by the requesting LAN. The requesting LAN adapter includes a control logic for transmitting a plurality of request signals (REQ) to the ATM crossbar switch, each of them being associated with a destination LAN, and the ATM crossbar switch comprises a scheduler for transmitting grant signals (GNT) associated with the requests enabling the requesting LAN adapter to transmit LAN data frames to the destination LANs. The grant signals are transmitted by the destination LAN in an order depending upon a predetermined algorithm that controls the scheduler regardless of the order the requests are transmitted by the requesting LAN adapter.

System for transmitting local area network (LAN) data frames

An improved data transmission system including multiple local area networks (LANs) coupled by a hub that further includes multiple LAN adapters coupled to the LANs, and an asynchronous transfer mode (ATM) crossbar switch coupling all LAN adapters. LAN data frames are converted into concatenated slots of an identical size and transmitted through the ATM crossbar switch. At least the requesting LAN adapter coupled to the LAN to transmit LAN data frame includes a serial communication controller (SCC) that converts a received LAN data frame into serial data. The SCC also includes a means for converting serial data to LAN data frames.

System for transmitting local area network (LAN) data frames through an asynchronous transfer mode (ATM) crossbar switch

A node for a telecommunications network has a segmentation and reassembly module (SAR module) to perform segmentation and reassembly (SAR) on cells received by the node, the SAR module particularly providing Virtual Channel Identifier (VCI) and Virtual Path Identifier (VPI) translation (referred to as VCI/VPI translation), and has a direct memory access (DMA) mechanism for a storage external to the SAR module, the SAR module performing a first DMA access when the VCI/VPI translation are representative of an error code correcting (ECC) procedure to be carried out in the node, and the SAR module performing a second DMA access when the VCI/VPI translation corresponds to a message that does not require a local ECC procedure. A coder/decoder module performs an ECC procedure on the cells. A controller controls the coder/decoder module to perform an error correcting procedure in response to the detection of the first DMA access. The first DMA access uses a first address and the second DMA uses a second address. A Reed-Solomon coder-decoder or a Hamming coder-decoder may be used to perform the ECC procedure. An address decoder interprets the VCI/VPI identifiers to control whether or not an ECC procedure is done.

ATM node having local error correcting procedures

The present invention describes a switching module for use either in port or speed expansion mode. The switching module is preferably used in a data transmission system consisting of a number of Local Area Networks LANs interconnected by a hub which includes a number of LAN adapters respectively connected to said LANs. A crossbar switch interconnects all LAN adapters and consists of switching modules having first receiving means for storing a first number of data packets; second receiving means for storing a second number of data packets; first outputting means for outputting a first subset of the first number of data packets and the second number of data packets; second outputting means for outputting a second subset of the first number of data packets; and switching means, coupled to the first and second receiving means and coupled to the first and second outputting means for routing the first and the second subsets of the first number of data packets and the second number of data packets to the respective first or second output means. The routing of the incoming data packets to their final destination is done without modifying the data packet header as a data packet sent by a source of adapter contains in its header the physical address of the destination adapter.

System for routing data packets through a crossbar switch in expansion mode

Data transmission system comprising a plurality of Local Area Networks (LANs) (-to-) interconnected by a hub () including the same plurality of LAN adapters (-to-) respectively connected to the LANs and a packet switch () interconnecting all LAN adapters wherein a packet transmitted by any adapter to the packet switch includes a header containing at least the address of the adapter to which the packet is forwarded. At each cross point is located a memory block for storing any data packet received from the input port corresponding to the cross point and which is to be forwarded to the output port corresponding to the cross point. The packet switch is composed of N&#xd7;N identical packet switch modules with each of the packet switch modules being associated with m input ports and m output ports and comprises a rank selector which is programmed to provide a rank k from 0 to N&#x2212;1 to each column of N modules corresponding to the same output ports, this rank being provided to all memory blocks of the column in order to shift the physical address of each output port in the column by an offset of k&#xd7;m.

Self-route multi-memory packet switch adapted to have an expandable number of input/output ports

A method and system for dynamically inverting an A symmetric Digital Subscriber Line (ADSL) system. The ADSL system includes a central exchange equipment (CE) connected to a service provider network and a user equipment (UE) connected to a user workstation. The CE and UE are interconnected by a PSTN link. The CE includes an ADSL transceiver and a splitter coupled between the CE transceiver and the PSTN link. The splitter includes a low-pass filter for separating low frequency voice signals from high frequency ADSL signals transmitted from the UE. In accordance with the method of the invention, an invert request message encoded as a tone sequence is generated by the UE and transmitted to the CE over the PSTN link. The tone-encoded invert request is received through the CE splitter low-pass filter and is decoded utilizing a tone decoder communicatively coupled between the CE splitter low-pass filter and the CE transceiver.

Method and system for dynamically inverting an asymmetric digital subscriber line (ADSL) system

Data transmission system comprising a plurality of Local Area Networks (LANs)( - to - ) interconnected by a hub ( ) including the same plurality of LAN adapters ( - to - ) respectively connected to the LANs and a packet switch ( ) comprising at least a packet switch module interconnecting all LAN adapters wherein a packet transmitted by any adapter to the packet switch includes a header containing at least the address of the adapter to which the packet is forwarded. At each cross point is located a memory block for storing any data packet received from the input port corresponding to the cross point and which is to be forwarded to the output port corresponding to the cross point. The system comprises a memory control circuit associated with each memory block within the packet switch for detecting an overflow, a regulating circuit for preventing a further data packet from being stored in the memory block which overflows in response to the memory control block, and an overflow bus for carrying the data packet to another memory block which does not overflow and corresponding to the same output port as the memory block which overflows.

Growing community of inventors

Villeneuve Loubet, France

Gilles Toubol