Abstract: A router includes a first processing module (1) adapted to route primary resources as a function of instructions received, inputs (2) adapted to feed the first processing module (1) with primary resources, outputs (3) adapted to collect primary resources switched by said first processing module (1), a second processing module (6) adapted to process secondary resources to be added or dropped, and coupling means (9) including a drop bus (8) and/or an add bus (7) and adapted, on the instructions of the control means (15), to drop either the whole of a primary resource arriving at one of said inputs (2) and/or outputs (3) or a portion thereof to feed said second processing module (6), and/or to add a secondary resource processed by said second processing module to a primary resource received at one of said inputs (2) and/or outputs (3) and in transit to a common destination.

Abstract: In a network comprising an optical link transporting packet streams consisting of successive optical packets separated by voids, the station comprises a transmission device (13) coupled to the link at an insertion point in order to inject optical packets into the link. At a detection point on the link, upstream of the insertion point, a detection device (11) observes the packet streams transported to this detection point. As a function of this observation each packet awaiting transmission and transmitted by the transmission device (13) causes the formation at the insertion point of a downstream packet stream containing the transmitted packet interposed between first and second packets delimiting a void of the upstream stream. The detection device (11) forms a transmission control signal (ACK) such that in the event of transmission as a function of this control signal, any transmitted packet is attached to at least one of the first and second packets.

Abstract: Packets conveying data are received by a router via input ports which impose on them optical carrier waves whose wavelengths correspond to the ports. Respective time-delays are applied to the packets and they are broadcast to spatial selectors that transmit them to spectral selectors. Amplifiers are distributed over the paths of the packets and the paths are organized in such a manner as to limit the number of semiconductor optical switches in the selectors and to minimize noise and optical crosstalk affecting the packets.

Abstract: A packet-switched communications network (PSN) includes a multiplicity of nodes (Ni) adapted to switch streams of packets benefiting from circuit emulation services, known as CES packets. The network uses a particular method of resynchronizing the CES streams. According to that method, for a CES stream intended to take an associated path (CE) from an ingress node (N1) passing through a set of nodes including a subset of nodes adapted to resynchronize CES streams selectively, effective resynchronization of said stream by a node selected from said subset is conditioned by a value representative of the cumulative jitter suffered by said stream as far as that node.

Abstract: An optical demultiplexer system for separating adjacent wavelength bands without losing inter-band channels and comprising a first filter stage (210) of relatively narrow passband and relatively high selectivity in order to extract all of the inter-band channels. The first stage is followed by a second filter stage (240) of relatively broad passband and relatively low selectivity to extract the wavelength bands delivered by the first filter stage. Such a system makes it possible to use the inter-band channels, in particular for managing the network and the wavelength bands.

Abstract: The network comprises an optical interconnection tree linking sending points of stations to a receiving point of a concentrator via access links (F1-F3), a coupling system (C) and a common optical link (OL). The stations can send optical signals (?u1, ?u2, ?u3) each carried by the same “uplink” wavelength (?u). Each station includes a carrier detection system able to detect the presence at its sending point (Ki) of an optical wave at said uplink wavelength (?u) that was not sent by the same station. The detection system cooperates with sending control means to inactivate sending if such presence is detected. The network further includes: an emulator (LDa, Ca, G1-G3) adapted to send auxiliary waves (?a1, ?a2, ?a3) at said uplink wavelength (?u) and to couple them into the access links (F1-F3) so that they propagate in the downlink propagation direction; and a control system (2a) of the emulator for selectively activating the sending of the auxiliary waves.

Abstract: A method is dedicated to transmitting data between nodes (Ni) of a group of nodes coupled to an access bus (L2-LSP) of a communications network (R1).

Abstract: Dynamic method of adding data at the nodes of a fiber optic transmission network comprising at least one source node, one destination node and a plurality of intermediate nodes, the nodes being connected by a fiber optic connection. The method comprises the steps of creating at the source node an optical resource comprising portions containing data packets addressed to said destination node and free portions that may be occupied by packets supplied by each of said intermediate nodes, when said resource transits an intermediate node, detecting if said resource comprises free portions if said intermediate node has at least one data packet to transmit, and adding said data packet to a free portion of the frame if said free portion may contain said data packet.

Abstract: The field of the invention is that of switching optical signals with carrier wavelength conversion capacity, comprising a set of input ports (PE1-PEn), a set of output ports (PS1-PSn) functionally connected to the input ports so that an input signal presented to one of the input ports may be selectively routed to at least one of the output ports, and wavelength conversion means (34) providing a capacity for converting an input signal carrier wavelength to at least one other output port output wavelength.

Abstract: The invention relates to a laser device for optical packet data transmission. Such devices are basically known in the art and comprise a laser light source for outputting a laser light beam and a laser driver for driving said laser light source. The laser device further comprises an optical modulator means for modulating a packet data stream onto said laser light beam. The optical modulator means presently available on the market, only have a low extinction rate; consequently residual light is output by said optical modulator means, even if a logical zero shall be transmitted.

Abstract: A communications station (4-i) for a WDM ring network is adapted to insert into an optical fiber (2) packets of optical signals carried by at least one wavelength and having a propagation direction in common with at least one other communications station.

Abstract: The invention relates to optical ring network comprising stations (340) which are connected to at least one optical fiber by means of the couplers, the two ends of the optical fiber being connected to a point of presence or an optical network access node. The point of presence comprises (k)at least an optical emitter (330-1) which emits a falling optical signal having at lest one first wavelength (420) in the direction of one end oft he optical fibers (455) and (ii) at least one optical receiver (330-2) which receives a rising optical signal having at least one second wavelength which is different from the first wavelength. The aforementioned optical network access node comprises mean such as a hub (320) which can be used for the communication between the optical receiver (320-2) and the optical emitter (330-1). The wavelength of rising signals and the wavelength of the following signals are shared by several stations.

Abstract: A method for synchronizing optical signals conducted via different optical waveguides to an optical network node, wherein the variations in propagation time of the optical signals are compensated by adjustable optical delay circuits of a synchronizing device. To set a new delay for one of the optical waveguides, one of the adjustable delay circuits, already switched into the passive state, is set at the desired delay. This delay circuit is then switched into the active state by means of a high-speed optical switch, and the previously active delay circuit is switched into a passive state.

Abstract: An optical ring network comprises “active” first and second optical fibers (2 and 3), each connected via at least one of its two ends to an access node and optically coupled to stations (4), the fibers being dedicated respectively to transferring data to said stations and to transferring data from said stations. Each station (4) also has monitoring means (10) capable of determining whether the station is authorized to transmit data over the active second fiber (3), and the access node has transfer means arranged to transfer onto the active first fiber (2) any data conveyed by the active second fiber (3) and addressed to at least one of the stations.

Abstract: The invention relates to a switch (112) for optical signals and which has a number of outputs at least equal to the number of inputs and include means whereby an input signal is routed to at least one of those outputs. Each input receives information modulating optical carriers at different wavelengths. The switch (112) includes means (12611, 12612, . . . , 126NB) for grouping all the carriers received into non-contiguous subsets of carriers (G11, . . . , G1B, . . . , GN1, . . . , GNB) and means (1291, 1292, . . . , 129NB) for selecting blocks of carriers from the same subset of carriers. The information corresponding to each subset of optical carriers is thus routed in blocks to the same subset output. Switching the carriers at the subset level improves the quality of the output signal and limits the number of components for the same total quantity of information switched.

Abstract: To increase the bit rate of wavelength division multiplexed optical data switched in a photonic switching matrix, whilst maintaining a high bandwidth, a wavelength selector and converter includes a demultiplexer with n outputs respectively connected to n inputs of a coupler via n wavelength converters. Each wavelength converter has an optical gate function and selectively supplies converted signals conveyed by the same wavelength. Applications include optical packet switching.

Abstract: In order to be able to use a semiconductor light amplifier of conventional type and operating under gain saturation conditions while nevertheless providing constant gain for an optical signal to be amplified, the device comprises means for producing a compensation light wave and coupling means for injecting the optical signal to be amplified and the compensation light wave into the amplifier. The compensation light wave presents amplitude modulation such that when combined with the optical signal to be amplified the overall amplitude modulation is eliminated or at least attenuated. The device is applicable to optical transmission systems operating at a single wavelength or with wavelength division multiplexing.

Abstract: An optical packet node for receiving and transmitting optical packets is presented, which comprises: a multiwavelength band splitting device for splitting received optical packes transmitted via multiwavelength bands into at least three groups, each group including one multiwavelength band, a multiwavelength band combining device for combining said at least three groups of multiwavelength bands, at least two optical packet add drop multiplexers, each optical packet add drop multiplexer being placed between said multiwavelength band splitting device and said multiwavelength band combining device, and each optical packet add drop multiplexer serving to add and to drop at least one individual wavelength to a respective group of a multiwavelength band, and a load balancing stage being connected to at least two of said optical packet add drop multiplexers, to provide an interconnection between at least two wavelength bands.

Abstract: A photonic switching device for switching without contention data in the form of optical packets includes a space switching matrix with a plurality of input ports and a plurality of output ports. A unit external to the space switching matrix includes a buffer memory common to all the output ports of the matrix. Each of the output ports provides access to the buffer memory via a space switching stage consisting of switches having a 1-to-2 switching function.

Abstract: Packets conveying data are received by a router via input ports which impose on them optical carrier waves whose wavelengths correspond to the ports. Respective time-delays are applied to the packets and they are broadcast to spatial selectors that transmit them to spectral selectors. Amplifiers are distributed over the paths of the packets and the paths are organized in such a manner as to limit the number of semiconductor optical switches in the selectors and to minimize noise and optical crosstalk affecting the packets.