Alcatel N.v.

Michel A Henrion

Henri A Verhille

Bart J Pauwels

Michel P De Somer

Apparatus for managing relationships between objects

An asynchronous switching node is described for distributing cells from an input port (I1, . . . , IN) of a node (ND) to a group of output ports (LG1, . . . , Lgk) thereof. The asynchronous switching node includes switching stages (S1, S2, S3) each having a switching element (S11, . . . , S3N) with inlets (IP1-IPN) and outlets (OP1-OPN). Each switching element (S11, . . . , S3N) has a routing logic circuit (MC1; MC2; RL) for routing one of the cells from one of the inlets (IP1-IPN) of one of the switching element (S11, . . . , S3N) to one of the outlets (OP1-OPN) thereof based on an internal routing label (LGA; SRT) associated with a cell. The switching element (S11, . . . , S3N) uses the internal routing label (LGA; SRT) to identify at least one distribution tree having branches (BR1, . . . , BR6 ) which connect the input port (I1, . . . , IN) with the group of output ports (LG1, . . . , Lgk). The routing logic circuit (MC1; MC2; RL) has a preselection circuit (MB; M; RM) for preselecting under the control of the internal routing label (LGA; SRT) a set of the branches (BR1, . . . , BR6), has a selection circuit (MX; MX'; SEL) for dynamically selecting one of the branches (BR1, . . . , BR6) and has an identifier circuit for identifying a route on a selected outgoing branch (BR1, . . . , BR6) from the one switching element (S11, . . . , S3N).

Asynchronous switching node and routing logic means for a switching

A cell resequencing system is provided for a resequencing section (RS) of a telecommunication network through which cells of communications are transmitted. The resequencing section includes cell switching networks (SN2) having inlets (I2l/I2n/I2N) coupled to inputs (S1l/S1n/S1N) and outlets (N2l/N2m/N2M). The cells are subjected to a first variable time delay. The cell resequencing system (C1l/C1n/C1N, CK1; R2l/R2m/R2M, CK2) includes latches (R2l/R2m/R2M) coupled between the outlets (N2l/N2m/N2M) and the outputs (S2l/S2m/S2M) to subject the cells to a second variable time delay chosen for each cell so the sum of the first and second variable time delay is substantially equal to a predetermined constant time value, which determines the size of the latches (R2l/R2m/R2M). The resequencing section (RS) has two inputs (S1l, S1n/S1N) each coupled to a distinct inlet (I2l/I2n/I2 N) via a distinct transmission link (TLl/TLn/TLN). The cells are subjected to at least a fixed transfer delay (TD) during their transfer from the input (S1l/S1n/S1N) to the outlet (N2l/N2m/N2M). The fixed transfer delay forms part of the first variable time delay. The minimum size of the latches (R2l/R2m/R2M) is determined by a difference between a predetermined constant time value and the fixed transfer delay (TD).

Cell resequencing system for a telecommunication network

The addresses of an irregular group of outputs of an asynchronous switching node distributing cells dynamically to outputs constituting an irregular group cannot be related by any mathematical relationship. To distribute cells applied to inputs of the node as regularly as possible, the node includes translator circuits determining at the network input an internal routing label which identifies a regular subgroup of outputs, each of which may consist of only one output. To this end it uses an algorithm dependent on the rank of the input receiving the cell and the time at which the cell is received. This algorithm therefore achieves spatial decorrelation and temporal decorrelation of the cells. The asynchronous switching node can be used in ATM telecommunication networks, for example.

Asynchronous switching node distributing cells dynamically to outputs

Routing logic (RL) for a communication switching element (ISE) of a self-routing multi-stage switching network and able to transfer cells or packets of information from any of its inlets (I1/32) to any of its outlets (O1/32). The outlets of the switching element are arranged in routing groups containing one or more of them and of which the identity is derived by the routing logic from an output-port-address (OPA) identifying an output of the switching network and contained in the self-routing-tag (SRT) associated to the cell. This cell is then transferred to one of the outlets belonging to the selected routing group. The routing logic (RL) is also able to control the transfer of a cell through the switching element according to the execution of a predetermined routing function selected amongst a plurality of routing functions (RS, DI, MC, BH, IS). This routing function to be executed is selected by the routing logic according to a routing-control-code (RCC) also contained in the self-routing-tag (SRT) and each value thereof identifies a specific transfer pattern constituted by a predetermined sequence of routing functions to be executed in the switching elements (ISE) through the switching network (SN).

Routing logic means for a communication switching element

Data is sent over a transmission link in consecutive variable length blocks in asynchronous transfer mode. Each block is either a data block if it contains data or an empty block if it does not. Each data block includes a header sub-block of a first type containing service data and at least one data sub-block of a second type containing data. Each empty block includes an empty sub-block of a third type. The sub-blocks of one of the three sub-block types have a length different from the respective lengths of the sub-blocks of the other two types.

Method and system for sending data over a transmission link in variable

A telecommunication system for transmitting cells through switching nodes (N1-3) interconnected by groups (LG12, LG23) of transmission links, each node including an asynchronous switching network (SN1-3) which comprises several switch elements. At least one of these switch elements possesses a routing group possibility whereby the cells are distributed over its outlets and so further over the different transmission links of the link group to which the switching network is connected. This distribution is performed in function of a self-routing tag which is derived from external routing data associated with the cell. At the input ports of either each or only the first switching network (SN1) of the system, the external routing data is translated in a self-routing tag which is for instance added to the header of the cell, while at the output ports of each or of only the last switching network (SN3) of the system respectively, the self-routing tag is removed from this header. Some switch elements possess a multicast possibility whereby the cells are transferred to several outlets thereof and thereby to several link groups to which the switching network is connected.

Telecommunication system

A novel packet-oriented multiple path self-routing switching network for switching asynchronous time-division multiplexed packets is characterized in that each switch unit of at least one upstream stage of the switching network includes means for defining an available state in which the downstream switch unit is available for routing packet traffic and for transmitting availability status information to upstream switch units when the downstream switch unit is in that available state, and is further characterized in that each upstream switch unit includes means for receiving availability status information for those outputs leading to a switch unit in the available state, and for prohibiting access to any output for which such availability status information is not received.

Multiple path self-routing switching network for switching asynchronous

Multiple path, self-routing switching network for switching asynchronous

Resequencing system for a switching node (SN) of a cell switching system wherein cells or packets, of fixed or variable length, transmitted from an input to an output of a switching network (SNW), are subjected in the network to variable initial time delays for instance because they follow different paths therein. To restore at the output the sequence with which the cells were supplied to the input the cells at the output are subjected to additional variable complementary time delays which are so chosen that for each cell the sum of the two time delays is substantially equal to a predetermined total value.

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Brussels, Belgium

Michel A Henrion